Cup alignment systems and methods

Abstract

To provide improved systems and methods for determining pelvic mobility and other patient specific kinematic data pre-operatively.SOLUTION: A system 10 can include a module 100 to measure mobility, such as pre-operative pelvic mobility, for surgical planning. The module can include one or more inertial sensors that can be positioned relative to the anatomy of a patient. Hip navigation systems can guide an acetabular cup to patient-specific target angles, based in part, on the pre-operative pelvic mobility of the patient.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] Incorporation by reference to priority applications Any and all applications to which foreign or domestic priority is claimed, including U.S. Provisional Patent Application No. 62 / 945,591, filed December 9, 2019, which is incorporated by reference herein in its entirety under 37 CFR 1.57, are identified in the Application Data Sheet filed herewith.

[0002] This application is directed to the field of hip replacement, and in particular to surgical instruments and methods for pre-operatively determining pelvic mobility. This application is also directed to determining or suggesting patient-specific target angles for cup placement. This application is also directed to the use of inertial sensors to collect kinematic or positional data. [Background technology]

[0003] Hip replacement surgery is common and is becoming more common each year. One persistent problem with hip replacement is poor placement of the cup component of the prosthetic hip joint. For example, the cup is optimally positioned in a specific abduction and anteversion orientation. Although an acceptable range of deviation from the optimal abduction and anteversion angles has been observed in clinical practice, for several reasons, an unacceptably high percentage of patients have prosthetic hip cups that fall outside of this range.

[0004] Unfortunately, misalignment can result in hip dislocation as quickly as one year after the implantation procedure. This is particularly problematic because recovery from a hip procedure can take many months. Patients who undergo revision soon after the initial implantation are understandably less satisfied with their treatment because they undergo an additional, unnecessary surgery. Of course, all surgery carries some degree of risk. These poor outcomes are frustrating for patients and inefficient for the health care system as a whole. Summary of the Invention [Problem to be solved by the invention]

[0005] There is a need for improved systems and methods for determining pelvic mobility and other patient-specific kinematic data pre-operatively. There is also a need for improved systems and methods for improving the alignment of hip joint components with a patient's anatomy during a hip replacement procedure by utilizing patient-specific kinematic data. These improved systems and methods can involve the use of pre-operative inertial sensors to determine pelvic mobility. The sensors can provide the surgeon with useful information for use in selecting patient-specific targets. These improved systems and methods can involve improving a patient-specific target angle for cup placement. These improved systems and methods can involve inertial guidance of a cup insertion device to a patient-specific target angle during hip replacement surgery. These improved systems and methods can involve adjusting the anteversion cup angle based on pre-operative kinematic information. These sensors can also provide useful information for patient positioning during the surgical procedure. [Means for solving the problem]

[0006] In one embodiment, a system is provided. The system may include a module including one or more inertial sensors configured to be positioned relative to a patient's anatomy. In one embodiment, the module is configured to measure mobility for surgical planning.

[0007] In some embodiments, the module includes a biocompatible adhesive configured to adhere the object to the patient's skin. In some embodiments, the module is embedded in clothing. In some embodiments, the one or more inertial sensors comprise an accelerometer. In some embodiments, the one or more inertial sensors comprise a gyroscope. In some embodiments, the module is configured to transmit data from the module to an external output device. In some embodiments, the external output device is a smartphone. In some embodiments, the system may include a smartphone. In some embodiments, the smartphone is configured to receive patient-specific data obtained from the module. In some embodiments, the external output device is a surgical orientation device configured to be used during a surgical procedure. In some embodiments, the system may include the surgical orientation device. In some embodiments, the surgical orientation device is configured to receive patient-specific data obtained from the module.

[0008] In some embodiments, a system is provided. The system may include a surgical orientation device including an inertial sensor. In some embodiments, the surgical orientation device is configured to facilitate guidance of an acetabular cup to a desired target angle. In some embodiments, the surgical orientation device detects the orientation and rotation of the device relative to a reference frame. In some embodiments, the surgical orientation device is configured to receive one or more mobility measurements for surgical planning.

[0009] In some embodiments, the system may include an orientation sensing device. In some embodiments, the surgical orientation device includes a transceiver for transmitting data or receiving data from one or more sensors of the orientation sensing device. In some embodiments, the surgical orientation device includes a transceiver for transmitting data or receiving data from a module configured to measure mobility. In some embodiments, the surgical orientation device includes a transceiver for transmitting data or receiving data from an external output device. In some embodiments, the external output device is a smartphone. In some embodiments, the smartphone is configured to receive patient-specific data obtained from the module.

[0010] In one embodiment, a method for determining patient mobility is provided. The method may include positioning a module comprising one or more inertial sensors relative to the patient's anatomy. The method may include measuring the mobility with the module.

[0011] In some embodiments, the mobility is pelvic mobility. In some embodiments, positioning the module includes positioning the module on the patient's sacrum. In some embodiments, positioning the module includes positioning the module on the patient's femur. In some embodiments, positioning the module includes positioning the module on the patient's spine. In some embodiments, positioning the module includes positioning the module on the patient's ASIS point. In some embodiments, positioning the module includes positioning the module on a bony prominence identified by palpation of the patient's skin. In some embodiments, positioning the module includes positioning the module on the patient's skin overlying the patient's underlying anatomy. In some embodiments, positioning the module includes positioning the module on the patient's pubic bone. In some embodiments, positioning the module includes positioning the module on a palpable location on the patient's body. In some embodiments, positioning the module includes positioning the module on the patient's lower back. In some embodiments, positioning the module includes positioning the module on the patient's upper back. In some embodiments, positioning the module includes positioning the module on the patient's neck. In some embodiments, positioning the module includes positioning the module on the patient's pelvis. In some embodiments, positioning the module includes positioning the module on the patient's tibia. In some embodiments, positioning the module includes positioning the module on the patient's vertebrae. In some embodiments, positioning the module includes positioning the module on the patient's sternum. In some embodiments, positioning the module includes positioning the module on the patient's ribs. In some embodiments, positioning the module includes positioning the module on the patient's skull.In some embodiments, the step of positioning the module includes positioning the module on a facial bone of the patient. In some embodiments, the step of positioning the module includes positioning the module on a humerus of the patient. In some embodiments, the step of positioning the module includes positioning the module on a scapula of the patient. In some embodiments, the step of positioning the module includes positioning the module on a clavicle of the patient. In some embodiments, the step of positioning the module includes positioning the module on an ulna of the patient. In some embodiments, the step of positioning the module includes positioning the module on a radius of the patient. In some embodiments, the step of positioning the module includes positioning the module on a carpal bone of the patient. In some embodiments, the step of positioning the module includes positioning the module on a fibula of the patient. In some embodiments, the step of positioning the module includes positioning the module on a tarsal bone of the patient. In some embodiments, the step of positioning the module includes positioning the module on a metatarsal bone of the patient. In some embodiments, the step of positioning the module includes positioning the module on the patient for one or more hours. In some embodiments, positioning the module includes positioning the module on the patient for one or more days. In some embodiments, positioning the module includes positioning the module on the patient for one or more weeks. In some embodiments, the one or more inertial sensors comprise an accelerometer. In some embodiments, the one or more inertial sensors comprise a gyroscope. In some embodiments, the method may include transmitting data from the module to an external output device. In some embodiments, the external output device is a smartphone.

[0012] In one embodiment, a method for positioning a medical prosthesis is provided. The method may include considering pre-operative measurements of pelvic mobility, the measurements collected with a module including one or more inertial sensors. The method may include determining a patient-specific target angle taking into account the pre-operative pelvic mobility. The method may include aligning a cup to the patient-specific target angle. The method may include fitting the cup.

[0013] In some embodiments, the one or more inertial sensors comprise an accelerometer. In some embodiments, the one or more inertial sensors comprise a gyroscope. In some embodiments, the method may include transmitting data from the module to an external output device. In some embodiments, the external output device is a smartphone. In some embodiments, the method may include determining a change in leg length before and after cup placement. In some embodiments, the method may include determining a change in leg length between the two legs. In some embodiments, the method may include determining a change in joint misalignment before and after cup placement. In some embodiments, the method may include projecting a pattern of light onto the patient's leg before fitting the cup and recording the incidence of the light. In some embodiments, the method may include projecting a pattern of light onto the patient's leg after fitting the cup and repositioning the leg to align the recording of the incidence of the light with the pattern of light. In some embodiments, the method may include recording points before and after fitting the cup. In some embodiments, the method may include establishing a vertical plane. In some embodiments, the method may include establishing a horizontal plane, where the vertical plane and the horizontal plane define a reference frame. In some embodiments, the patient-specific target angle is measured relative to the vertical plane. In some embodiments, the method may include establishing a reference plane. In some embodiments, the method may include establishing a reference plane including positioning an indicator to contact a first point and recording a position and / or orientation of the indicator when the indicator is contacting the first point, positioning the indicator to contact a second point and recording a position and / or orientation of the indicator when the indicator is contacting the second point. In some embodiments, the establishing the reference plane further includes positioning an indicator to contact a third point and recording a position and / or orientation of the indicator when the indicator is contacting the third point. In some embodiments, the first point, the second point, and the third point define an anterior pelvic plane.In some embodiments, establishing the reference plane further comprises positioning the indicator horizontally. In some embodiments, the first point and the second point define a line that intersects the contralateral ASIS.

[0014] In one embodiment, a method is provided. The method may include positioning a module comprising one or more inertial sensors relative to a patient's anatomy. The method may include measuring patient-specific pelvic mobility with the module comprising one or more inertial sensors. In one embodiment, the patient-specific pelvic mobility is considered to determine at least a portion of the surgical plan.

[0015] In some embodiments, patient-specific pelvic mobility is considered to determine a target angle. In some embodiments, patient-specific pelvic mobility is considered to determine an implant type. In some embodiments, patient-specific pelvic mobility is considered to determine an appliance type. In some embodiments, patient-specific pelvic mobility is considered to determine leg length. In some embodiments, patient-specific pelvic mobility is considered to determine a joint misalignment. In some embodiments, the one or more inertial sensors comprise an accelerometer. In some embodiments, the one or more inertial sensors comprise a gyroscope. In some embodiments, the method may include transmitting data from the module to an external output device. In some embodiments, the external output device is a smartphone.

[0016] In one embodiment, a hip joint guidance system is provided. The hip joint guidance system may include a first inertial guidance device including one or more inertial sensors. The hip joint guidance system may include an indicator. The hip joint guidance system may include a second inertial guidance device including one or more inertial sensors. In one embodiment, the first inertial guidance device, the second inertial guidance device, or the first inertial guidance device and the second inertial guidance device are configured to align the cup to a patient-specific target angle, the patient-specific target angle being determined based on pre-operative pelvic mobility.

[0017] In some embodiments, the system may include a module including one or more inertial sensors and configured to measure pre-operative pelvic mobility. In some embodiments, the first inertial guidance device includes a transceiver for transmitting data or receiving data from the module. In some embodiments, the second inertial guidance device is configured to couple to the impactor. In some embodiments, the hip joint guidance system may further include a universal impactor adapter including a coupler, where the second inertial guidance device is configured to couple to the impactor with the adapter. In some embodiments, the hip joint guidance system may include an optical element.

[0018] In one embodiment, an orthopaedic surgical guidance system is provided. The orthopaedic surgical guidance system may include a module configured to generate an output that prescribes at least a portion of a surgical plan based on pre-operatively measured joint mobility. The orthopaedic surgical guidance system may include a user interface configured to display information related to the output during surgery.

[0019] In some embodiments, the system may include a module including one or more inertial sensors and configured to measure pre-operative joint mobility. In some embodiments, the modules include a transceiver for transmitting or receiving data between modules. In some embodiments, the display indicates the type of implant to be used in the orthopaedic surgical procedure. In some embodiments, the display indicates the use of a dual-mobility hip implant. In some embodiments, the display indicates one or more target angles toward which a surgical instrument is to be aligned and / or one or more target locations toward which the surgical instrument is to be advanced. In some embodiments, the display indicates the proximity of a surgical instrument to the one or more target angles and / or one or more target locations. In some embodiments, the orthopaedic surgical guidance system may include a reamer, the system including a module configured to provide an output indicating a position and / or orientation of the reamer relative to the one or more target angles and / or one or more target locations, and the user interface configured to display the output indicating the position and / or orientation. In some embodiments, the orthopaedic surgical guidance system can include an impactor, the system including a module configured to provide an output indicating a position and / or orientation of the impactor relative to one or more target angles and / or one or more target locations, and the user interface configured to display the output indicating the position and / or orientation. In some embodiments, the orthopaedic surgical guidance system can include acquiring a reference frame. In some embodiments, the orthopaedic surgical guidance system can include acquiring a reference frame using a pointing device to establish a position and / or orientation of a point. In some embodiments, the orthopaedic surgical guidance system can include acquiring a reference frame using a pointing device to establish an orientation of an axis. In some embodiments, the orthopaedic surgical guidance system can include acquiring a reference frame using a pointing device to establish a position and / or orientation of an axis of gravity. In some embodiments, the orthopaedic surgical guidance system can include acquiring a reference frame using a pointing device to establish a position and / or orientation of a plane.In some embodiments, the orthopaedic surgical guidance system may include obtaining a frame of reference using a pointing device to establish the position and / or orientation of a plane that approximates an anatomical plane of the patient. In some embodiments, the orthopaedic surgical guidance system may include obtaining a frame of reference using a pointing device to establish the position and / or orientation of a plane that approximates an anatomical plane of the patient.

[0020] In an embodiment, a method is provided. The method may include positioning a module comprising one or more inertial sensors relative to a patient's anatomy. The method may include measuring patient-specific pelvic mobility with the module comprising one or more inertial sensors. In an embodiment, the patient-specific pelvic mobility is collected post-operatively.

[0021] In an embodiment, the method may include pre-operatively positioning a module comprising one or more inertial sensors relative to the patient's anatomy and pre-operatively measuring patient-specific pelvic mobility with the module comprising one or more inertial sensors. In an embodiment, the method may include comparing the pre-operative measurements with the post-operative measurements. In an embodiment, the pre-operative patient-specific pelvic mobility is considered to determine at least a portion of the surgical plan. In an embodiment, the post-operative patient-specific pelvic mobility is considered to determine at least a portion of the physical therapy plan.

[0022] These and other features, aspects, and advantages are described below with reference to the drawings, which are intended to illustrate, but not to limit, the invention, in which like reference numerals indicate corresponding features consistently throughout like embodiments. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view of the module in a patient's hand. [Figure 2] FIG. 1 is a diagram of components of a pre-surgical planning system. [Figure 3A] FIG. 2 is a perspective view of the module of FIG. 1 connected to a patient. [Figure 3B] FIG. 2 is a perspective view of the module of FIG. 1 connected to a patient. [Figure 3C] FIG. 2 is a perspective view of the module of FIG. 1 connected to a patient. [Figure 4] FIG. 2 illustrates one or more modules of FIG. 1 in communication with an external output device. [Figure 5A] FIG. 1 illustrates the pre-operative approach. [Figure 5B] FIG. 1 illustrates the pre-operative approach. [Figure 6] FIG. 1 is a diagram of an embodiment of a workflow. [Figure 7] FIG. 1 is a perspective view of a hip guide system coupled to a patient's pelvis. [Figure 8] FIG. 1 illustrates patient positioning for a posterior hip approach. [Figure 9] FIG. 2 illustrates the projection of light from an optical element. [Figure 10] FIG. 10 is a diagram illustrating a method of table registration. [Figure 11] 8 illustrates an embodiment of an impactor including the orientation sensing device of FIG. 7. [Figure 12] An example of an x-ray that may be taken before surgery. [Figure 13] FIG. 1 illustrates patient positioning for an anterior hip approach. [Figure 14] FIG. 1 illustrates a method for identifying the anterior pelvic plane. [Figure 15] FIG. 1 illustrates a method for identifying an adjusted plane. [Figure 16] FIG. 1 is a lateral view of the pelvis, anterior pelvic plane, and adjusted plane. DETAILED DESCRIPTION OF THE INVENTION

[0024] Discussed below are various systems and methods that can be used to increase the likelihood of proper placement of a medical prosthesis, such as an acetabular cup, and thereby improve patient outcomes. In certain embodiments, pre-operative planning systems and methods are utilized to measure characteristics of the patient's anatomy. In certain embodiments, intra-operative guidance systems and methods are utilized to guide the medical prosthesis to a desired angular placement relative to a reference plane.

[0025] A. Preoperative planning system for anterior and posterior approaches 1. Pre-operative planning system Discussed below are various modules, systems, and methods for total hip arthroplasty (THA) that can be used to improve patient outcomes by increasing the likelihood of proper placement of a medical prosthesis, such as an acetabular cup. These systems and methods may focus on understanding the patient's anatomy, such as pre-operative pelvic mobility and patient positioning during the procedure. These systems and methods may add functionality to measure, quantify, and / or track characteristics of pelvic mobility or patient positioning. These sensor measurements can inform the selection of patient-specific target abduction and anteversion angles for cup placement. These sensor measurements can enable the surgeon to determine the patient's position during the surgical procedure. These sensor measurements, as disclosed herein, may have various uses for improving patient outcomes.

[0026] FIG. 1 illustrates a module 100 adapted to determine one or more characteristics of a patient. The module 100 can determine kinematic information related to the patient. In one embodiment, the module 100 is configured to measure pelvic mobility. In one embodiment, the module 100 can be used to measure mobility of other joints. The module 100 can be used to measure mobility between the pelvis and the spine. The module 100 can be used to measure mobility between the pelvis and at least one femur. In one embodiment, the module 100 is configured to measure pelvic mobility, or a value equivalent to pelvic mobility. Although characterizing pelvic mobility is described herein, the module 100 can be used to measure any characteristic of patient movement or positioning. The modules may be utilized with any portion of the anatomy, including the spine, pelvis, femur, tibia, vertebrae, sternum, ribs, skull, facial bones, humerus, scapula, clavicle, ulna, radius, carpal bones, fibula, tarsal bones, metatarsal bones, and / or other bones or regions of the human body.

[0027] Module 100 can determine the position or orientation of a portion of a patient's anatomy relative to other portions. Module 100 can determine the position or orientation of a portion of a patient's anatomy relative to a coordinate system. In an embodiment, module 100 is configured to determine the position or orientation of a portion of a patient's anatomy relative to an axis of gravity. In an embodiment, module 100 is configured for dynamic measurements. In an embodiment, module 100 is configured for static measurements.

[0028] Module 100 may be used preoperatively to determine patient characteristics. In some embodiments, the preoperative information may be utilized by the surgeon during the surgical procedure. In some embodiments, the preoperative information may be utilized by the surgeon to determine a target cup angle. In some embodiments, the preoperative information may be utilized by the surgeon to modify the surgical plan based on patient-specific data. In some embodiments, the preoperative information may be utilized by the surgeon to adjust the cup angle based on patient-specific data. Module 100 may be used preoperatively to provide data for a subsequent surgical procedure. In some embodiments, module 100 may provide the surgeon with information about the target. In some embodiments, module 100 may provide the surgeon with information to modify a target angle determined from a static image, such as an x-ray. In some embodiments, module 100 may suggest adjustments to the target angle. The surgeon may determine a patient-specific target angle. In some embodiments, the preoperative information may be utilized in other ways, as described herein.

[0029] The patient-specific target angle can be an input to a system that allows navigation to the patient-specific angle. In some ways, module 100 can be used intraoperatively. Module 100 can determine patient positioning. Module 100 can provide additional data related to a frame of reference. Module 100 can facilitate alignment of the patient's anatomy. In some embodiments, module 100 can be utilized in other ways, as described herein.

[0030] Module 100 may be used post-operatively to determine patient characteristics. In some embodiments, the post-operative information may be utilized by a surgeon or physician to determine the outcome of a surgical procedure. In some embodiments, the post-operative information may be utilized by a surgeon or physician to modify a patient's behavior. In some embodiments, the post-operative information may be utilized by a surgeon or physician to modify a patient's post-operative plan. In some embodiments, the post-operative information may be utilized by a surgeon or physician to modify post-operative physical therapy. In some embodiments, the post-operative information may be utilized in other ways, as described herein.

[0031] In some embodiments, module 100 can provide information that allows a surgeon to classify a patient. In some embodiments, module 100 can provide information that allows a surgeon to modify a population target angle to a patient-specific target angle. In some embodiments, the patient-specific information from module 100 can provide information to a surgeon to change the anteversion angle for cup placement. In some embodiments, the patient-specific information from module 100 can provide information to a surgeon to change the abduction angle for cup placement. In some embodiments, the patient-specific information from module 100 can provide information to a surgeon to modify the target angle for cup placement. In some embodiments, module 100 is configured to facilitate the determination of a patient-specific target angle for cup placement.

[0032] In some embodiments, the patient-specific information from module 100 can provide guidance to a surgeon in prosthesis selection. The patient-specific information from module 100 can provide guidance to a surgeon to select a prosthesis from two or more prostheses. In some embodiments, the patient-specific information from module 100 can provide information to a surgeon to select a dual mobility implant.

[0033] In one embodiment, module 100 can transmit data for display. Module 100 can be configured to show pelvic angle values. Module 100 can be configured to show patient-specific target angle suggestions. Module 100 can be configured to show kinematic data. Module 100 can be configured to show position data. Module 100 can be configured to determine suggestions. Module 100 can be configured to process the data into a surgeon-readable form. Module 100 can be configured to process the data into a bulleted list. Module 100 can be configured to process the data into a graph. Module 100 can be configured to process the data into verbal suggestions.

[0034] Module 100 may comprise a compact, generally handheld, and / or portable device. Module 100 may be used alone or with other devices, components, and / or systems, as described herein. In certain embodiments, module 100 may be used in conjunction with a surgical procedure. Module 100 may be used pre-operatively, post-operatively, and / or during a surgical procedure. In using module 100 with a surgical procedure, module 100 may be used in combination with a posterior approach for a total hip replacement. In using module 100 with a surgical procedure, module 100 may be used in combination with an anterior approach for a total hip replacement.

[0035] Module 100 can be used in combination with other components to form system 10. In some methods, system 10 is utilized as a pre-operative planning system. In some methods, system 10 is utilized as a post-operative planning system. In some methods, system 10 is utilized during a surgical procedure. FIG. 2 illustrates an embodiment of system 10. System 10 may include additional components. System 10 may omit any of the components described herein. System 10 may include one or more additional components. In some embodiments, two or more components of system 10 may be combined into a single component.

[0036] The module 100 can take any shape or form. In some embodiments, the module 100 may comprise a three-dimensional shape, such as a sphere, cone, cylinder, cube, rectangular prism, pyramid, toroid, spiral, or any other three-dimensional shape. In some embodiments, the module 100 may comprise a two-dimensional shape, such as a circle, triangle, square, rectangle, semicircle, oval, or any other two-dimensional shape. In some embodiments, the module 100 may not have a fixed shape. In the illustrated embodiment, the module 100 may comprise a generally rectangular-shaped structure, although other configurations are contemplated. In some embodiments, the module 100 may comprise a rigid structure. In some embodiments, the module 100 may comprise a flexible substrate. In some embodiments, the module 100 may comprise a shape or form that conforms to the patient's skin. In some embodiments, the module 100 may have an outer housing 102. The outer housing 102 may be portable. The outer housing 102 may be at least partially made of plastic, including ABS, polycarbonate, or other suitable material. The module 100 may be configured for handheld use. The outer housing 102 may include a front surface 104 that faces generally away from the user's body. The outer housing 102 may include a rear surface 106 that faces toward the user's body. The outer housing 102 may include one or more side surfaces 108.

[0037] In some embodiments, module 100 is reusable. Module 100 may be configured for multiple uses by the same patient. Module 100 may be configured for multiple uses by different patients. In some embodiments, module 100 may be cleaned or sterilized between uses. Module 100 may include an internal source of power, such as a battery. Module 100 may be reusable as long as the power source is functional. Module 100 may include a replaceable battery or power source. Module 100 may be configured to be opened by the patient or physician to replace the battery or power source. Module 100 may include a rechargeable battery or power source. Module 100 may be configured to be coupled to a charging device to resupply power to the battery or power source.

[0038] In some embodiments, module 100 is disposable. Module 100 may be disposable. In some embodiments, module 100 may be reused by placing module 100 in a disposable housing. This arrangement can maximize reuse of the internal components while maintaining the cleanliness of module 100. A disposable outer housing may comprise module 100 or may be releasably attached to module 100. The disposable outer housing may be manufactured and packaged in a sterile condition and provide a sterile barrier between the internal reusable components of module 100 and the external environment. Thus, once module 100 is used, the disposable outer housing may be disposed of or destroyed, and the internal reusable components may be reused.

[0039] The module 100 may include an indicator 110. The indicator 110 may be located on the front surface 104. The indicator 110 may be located on the side surface 108. The indicator 110 may be a light or LED that indicates that the module 100 is turned on. The indicator 110 may be a light or LED that indicates that the module 100 is sensing motion. The indicator 110 may be a separate component from the outer housing 102 or may be incorporated on or within the outer housing 102. In one embodiment, the indicator 110 is a display. The display may be sized so that a user can easily read numbers, letters, and / or symbols on the display while performing a medical procedure. The indicator 110 may provide a warning to the user when a specific condition occurs. The indicator 110 may include a visible output, such as one or more LED status or notification lights, to indicate, for example, a low battery level, an error condition, etc. The indicators 110 may include different patterns, colors, tones, durations, and / or frequencies to indicate different conditions or events.

[0040] The module 100 may include a user input device 112. The user input device 112 may be located on the front surface 104. The user input device 112 may be located on the side surface 108. The user input device 112 may include one or more buttons. The user input device 112 may include one or more switches. The user input device 112 may include one or more scroll wheels. The user input device 112 may be actuated, for example, by a finger, hand, and / or instrument, for example, to select a mode of operation of the module 100. The user input device 112 may be a component separate from the outer housing 102 or may be incorporated on or within the outer housing 102. In some embodiments, the user input device 112 is a component separate from the housing 102. For example, the user input device 112 may include a remote input device coupled to the module 100 via a wired or wireless connection. The user input device 112 may receive signals, such as signals to turn on or record measurements. The user input device 112 may receive a signal to turn off. The user input device 112 may receive a signal indicating the duration or time period for which the module 100 should record measurements. The module 100 may comprise means for receiving instructions.

[0041] The module 100 may comprise a means for coupling to a patient. The module 100 may be removably coupled to a patient. In some embodiments, the rear surface 106 of the module 100 may comprise a means for coupling to a patient. In some embodiments, the rear surface 106 comprises an adhesive. The adhesive may be any biocompatible adhesive configured to adhere an object to a patient's skin. In some embodiments, the adhesive may be coupled to or attached to the rear surface 106. The rear surface 106 may comprise an attachment structure. The attachment structure may facilitate attachment of the module 100 to another device or to a patient. In some methods, the module 100 may be positioned on a portion of the patient's body with slightly softer tissue. In some methods, the module 100 may be positioned on a portion of the patient's body near underlying anatomy. In some methods, the module 100 may be positioned on a portion of the patient's body at one or more palpable locations.

[0042] In some embodiments, the module 100 is coupled to a wrap or band. In some embodiments, the module 100 may be embedded in fabric. In some embodiments, the module 100 may be embedded in clothing. The module 100 may be integrally formed with fabric or clothing. The module 100 may be integrated with fabric or clothing. The clothing may be tight-fitting. The clothing may position the module 100 relative to the patient's anatomy. The clothing may be configured to position one or more modules 100 relative to the pelvis. In some embodiments, the clothing is a pair of shorts or pants. In some embodiments, the clothing is a t-shirt. The clothing may be made from any tight-fitting material, such as spandex, polyester, polypropylene, nylon, cotton, bamboo, neoprene, or any other material. In some embodiments, the module 100 is coupled to clothing configured to be worn by the patient. In some embodiments, the module 100 is wearable. In some embodiments, the module 100 may be wrapped around a portion of the patient's body. In some embodiments, the module 100 is a sleeve or strap.

[0043] In some embodiments, module 100 is configured to be external to the patient's body. Module 100 can be coupled to the patient's skin. Module 100 is configured to be easily coupled to the patient's body. Module 100 is configured to be easily removed from the patient's body.

[0044] The module 100 may be coupled to the patient for a period of time. In some methods, the module 100 is coupled to the patient for one minute or more, one hour or more, one day or more, one week or more, or any range of these values. In some methods, the module 100 is coupled to the patient for 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes, or any range between two of these values. In some methods, the module 100 is coupled to the patient for a portion of the clinical appointment time. In some methods, the module 100 is coupled to the patient for 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 21 hours, 22 hours, 23 hours, 24 hours, 36 hours, 48 ​​hours, 60 hours, 72 hours, or any range between two of these values. In some methods, the module 100 is coupled to the patient for a portion of a hospital or inpatient stay. In some methods, the module 100 is coupled to the patient for 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 14 days, 21 days, 28 days, or any range between two of these values. In some methods, the module 100 is coupled to the patient for a portion of pre-operative monitoring. In some methods, the module 100 is coupled to a patient for 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 11 weeks, 12 weeks, 13 weeks, 14 weeks, 15 weeks, 16 weeks, 17 weeks, 18 weeks, 19 weeks, 20 weeks, or any range between two of these values. In some methods, the module 100 is coupled to a patient for diagnostic purposes. In some methods, the module 100 is coupled to a patient for 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months, 10 months, 11 months, 12 months, or any range between two of these values. In some methods, the module 100 is coupled to a patient to monitor a condition.In some methods, the module 100 is coupled to the patient to monitor a change or deterioration in condition. In some methods, the module 100 is coupled to the patient continuously for a period of time. In some methods, the module 100 is coupled to the patient sporadically for a period of time. In some methods, the module 100 is coupled to the patient during a specific activity for a period of time. In some methods, the module 100 is coupled to the patient while walking for a period of time. In some methods, the module 100 is coupled to the patient while moving for a period of time. In some methods, the module 100 is coupled to the patient on a periodic basis, such as one hour every Monday or one day every week. In some methods, the module 100 is coupled to the patient according to a schedule. In some methods, the module 100 is coupled to the patient to record a desired amount of data for a desired period of time. In some methods, the module 100 is coupled to the patient for the duration of one or more movements. In some methods, the module 100 is coupled to the patient for the duration of one or more positions. In one method, the module 100 is coupled to the patient for the duration of the surgical procedure.

[0045] The module 100 may include gripping features 114 to facilitate handling of the module 100. In an embodiment, the gripping features 114 include grooves or ridges along a portion of the module 100. The gripping features 114 may be located on the front surface 104. The gripping features 114 may be located on the rear surface 106. The gripping features 114 may be formed, for example, from portions that protrude from the side surfaces 108. The gripping features 114 may extend partially or entirely along the side surfaces 108 of the module 100.

[0046] In some embodiments, module 100 may include one or more functional elements configured to sense position, orientation, or movement. Module 100 may include an electronic control unit 120 in communication with one or more sensors 122. In some embodiments, one or more sensors 122 include one or more inertial sensors. Module 100 may include a power supply 124. Module 100 may include internal memory 126. FIG. 2 illustrates electronic control unit 120, one or more sensors 122, and power supply 124. Electronic control unit 120 may be a separate component from outer housing 102 or may be integrated into or on outer housing 102. One or more sensors 122 may be separate components from outer housing 102 or may be integrated into or on outer housing 102. Power supply 124 may be a separate component from outer housing 102 or may be integrated into or on outer housing 102.

[0047] The module 100 can be used in combination with other components to form a system 10, such as that shown in FIG. 2 . The system 10 can include an external storage device 128. The module 100 can be in communication with the external storage device 128. The system 10 can include an external output device 130. The module 100 can be in communication with the external output device 130. In some embodiments, the external output device 130 can include the external storage device 128. The external storage device 128 can be a separate component from the external output device 130 or can be integrated onto or within the external output device 130. The system 10 can include the external output device 130 with which a user can interact. The external output device 130 can enable surgeons, medical personnel, and / or other users to operate the module 100 with ease, efficiency, and precision.

[0048] In one embodiment, the electronic control unit 120 receives input from one or more sensors 122. The electronic control unit 120 can control and / or transmit output to an external storage device 128. The electronic control unit 120 can control and / or transmit output to an external output device 130. The electronic control unit 120 can be configured to receive and transmit electronic data. The electronic control unit 120 can be configured to perform calculations based on the received electronic data. The electronic control unit 120 can include a transceiver. The electronic control unit 120 can communicate data wirelessly using Bluetooth®, Bluetooth Low Energy®, Wi-Fi®, or other standard telemetry protocols. The electronic control unit 120 can include a Bluetooth® radio. The electronic control unit 120 can include a Bluetooth Low Energy® radio.

[0049] In certain embodiments, electronic control unit 120 may be configured to convert electronic data from a machine-readable format to a human-readable format for display on external output device 130. Electronic control unit 120 may comprise one or more processing units, program logic, or other board configurations that represent data and instructions. Electronic control unit 120 may comprise controller circuitry, processing unit boards, processing units, general-purpose single-chip or multi-chip microprocessors, digital signal processors, embedded microprocessors, microcontrollers, and / or the like. Electronic control unit 120 may comprise conventional address lines, conventional data lines, and one or more conventional control lines. Electronic control unit 120 may comprise an application-specific integrated circuit (ASIC) or one or more modules configured to execute on one or more processing units. Electronic control unit 120 may comprise a microcontroller.

[0050] The electronic control unit 120 can communicate with the internal storage device 126 to read and / or save data. The electronic control unit 120 can communicate with the external storage device 128 to read and / or save data. The electronic control unit 120 can communicate with the internal storage device 126 and / or the external storage device 128 to read program instructions for software and / or hardware. The internal storage device 126 and the external storage device 128 can comprise random access memory ("RAM") for temporary storage of information, such as static RAM, and / or read-only memory ("ROM") for more permanent storage of information, such as flash memory. The external storage device 128 can be integrated with a cloud database. The external output device 130 can read data from the cloud database. One or more modules 100 can interact with the external storage device 128 via cloud integration. The external storage device 128 can be a server.

[0051] In an embodiment, electronic control unit 120 may be configured to provide continuous real-time data to external output device 130. In an embodiment, electronic control unit 120 may be configured to provide continuous data collection over a range of time. In an embodiment, electronic control unit 120 may be configured to generate multiple data points during patient movement (e.g., 10 data points, 100 data points, 500 data points, 1000 data points, or any range of these values). In an embodiment, electronic control unit 120 may be configured to generate multiple data points over a period of time (e.g., 10 data points per minute, 100 data points per minute, 500 data points per minute, 1000 data points per minute, or any range of these values).

[0052] The electronic control unit 120 may be configured to receive real-time data from one or more sensors 122. The electronic control unit 120 may be configured to use the sensor data to determine, estimate, and / or calculate pelvic mobility or to measure a value proportional to the patient's pelvic mobility. The electronic control unit 120 may be configured to use the sensor data to determine patient positioning. The mobility information may be used to determine patient-specific target angles for hip replacement surgery. The mobility information may be used to classify patients and modify a population average target angle. In an embodiment, the one or more sensors 122 facilitate pelvic mobility determination and / or patient positioning during preparation procedures performed before orthopedic surgical surgery.

[0053] In some embodiments, the one or more sensors 122 may comprise at least one orientation sensor configured to provide real-time data to the electronic control unit 120 related to the movement, orientation, and / or position of corresponding patient anatomy. In some embodiments, the one or more sensors 122 may comprise at least one gyroscope sensor, accelerometer sensor, tilt sensor, magnetometer, and / or other similar device. In some embodiments, the one or more sensors 122 may comprise an optional inductive sensor. In some embodiments, the one or more sensors 122 may comprise a non-inertial sensor. In some embodiments, the one or more sensors 122 may comprise any sensor capable of determining position. In some embodiments, the one or more sensors 122 may comprise any sensor capable of determining orientation. In some embodiments, the one or more sensors 122 may comprise any sensor capable of tracking movement. The one or more sensors 122 may be configured to measure and / or facilitate determining mobility of the patient anatomy underlying the one or more sensors 122. In an embodiment, one or more sensors 122 may be configured to provide measurements relative to a reference point, line, plane, and / or zero gravity. Zero gravity, as referred to herein, generally refers to an orientation in which the axis of the sensor is perpendicular to the force of gravity, thereby experiencing no angular misalignment, e.g., tilt, pitch, roll, or yaw, relative to the gravity vector. In an embodiment, one or more sensors 122 may be configured to provide measurements for use in a dead reckoning system or an inertial guidance system.

[0054] In one embodiment, the one or more sensors 122 may comprise one or more accelerometers that measure static acceleration of the patient's anatomy due to gravity. For example, the accelerometers may be used as tilt sensors to detect rotation of the patient's anatomy about one or more of its axes. The one or more accelerometers may comprise dual-axis accelerometers that can measure rotation about two axes of rotation. The one or more accelerometers may comprise tri-axis accelerometers that can measure rotation about three axes of rotation. Changes in orientation about the accelerometer axes may be determined relative to zero gravity and / or relative to any coordinate system described herein.

[0055] The output signal of the one or more accelerometers may include a digital signal. The one or more accelerometers may output the digital signal through a standard digital interface. The one or more accelerometers may output the digital signal through any protocol, including Inter-Card Interface (I2C). The one or more accelerometers may output the digital signal through any protocol, including Serial Peripheral Interface (SPI). The one or more accelerometers may output the digital signal through any protocol, such as Universal Asynchronous Receiver Transmitter (UART) or CAN protocol. The output signal of the one or more accelerometers may include an analog voltage signal. The output voltage signal for each axis may vary based on variations in static acceleration as the accelerometer changes its orientation relative to the gravity vector. In certain embodiments, the accelerometer is subjected to static acceleration in the range of -1g to +1g through 180 degrees of tilt, with -1g corresponding to a 90-degree tilt, 0g corresponding to a zero-degree tilt, and +1g corresponding to a +90-degree tilt. The acceleration along each axis may be independent of the tilt along the other axes.

[0056] A multi-axis accelerometer may be conceptualized as having a separate accelerometer sensor for each of its axes of measurement, with each sensor responding to changes in static acceleration in one plane. In certain embodiments, each accelerometer sensor is most responsive to changes in tilt (i.e., operates with maximum or optimal accuracy and / or resolution) when its sensitive axis is substantially perpendicular to gravity (i.e., when the accelerometer sensor's longitudinal plane is parallel to gravity) and least responsive when the sensitive axis is parallel to gravity (i.e., when the accelerometer sensor's longitudinal plane is perpendicular to gravity). In some embodiments, one or more sensors 122 may be mounted with an angular offset to improve the accuracy of one or more sensors 122.

[0057] In one embodiment, the one or more sensors 122 comprise at least one single-axis or multi-axis gyroscope sensor and at least one single-axis or multi-axis accelerometer sensor. The one or more sensors 122 may comprise a triaxial gyroscope sensor or three gyroscope sensors. The one or more sensors 122 may comprise a triaxial accelerometer or three accelerometer sensors. The one or more sensors 122 may provide position and orientation measurements for all six degrees of freedom of the module 100. In one embodiment, the one or more sensors 122 provide an inertial guidance or dead reckoning system to continuously calculate the position, orientation, and velocity of the module 100 without the need for an external reference.

[0058] In certain embodiments, the one or more sensors 122 comprise one or more accelerometers and at least one magnetometer. The magnetometer may be configured to measure the strength and / or direction of one or more magnetic fields in the vicinity of the module 100. The magnetometer may advantageously be configured to detect changes in angular position about a horizontal plane. In certain embodiments, the one or more sensors 122 comprise one or more sensors capable of determining distance measurements. The one or more sensors 122 may be in wired or wireless electrical communication with an emitter element attached to the end of a measurement indicator. In certain embodiments, the electrical control unit 120 may be configured to determine the distance between the sensor and the emitter, for example, the axial length of the measurement indicator corresponding to the distance to an anatomical landmark. In certain embodiments, the indicator is a probe.

[0059] In some embodiments, the module 100 can collect data relative to a reference system. In some embodiments, the module 100 can collect data relative to a coordinate system. The coordinate system can include two orthogonal planes. The coordinate system can include three orthogonal planes. The coordinate system can include two orthogonal axes. The coordinate system can include three orthogonal axes. One or more modules 100 can be registered to a global coordinate system. The global coordinate system can be utilized in one or more method steps. The global coordinate system can be utilized in cup guidance. The global coordinate system can be anatomically based. The global coordinate system can be determined pre-operatively. The global coordinate system can be determined intra-operatively. The global coordinate system can be determined from imaging techniques such as x-rays. The global coordinate system can include one or more anatomical axes. The global coordinate system can include one or more anatomical planes. The global coordinate system can include one or more planes determined from gravity.

[0060] The modules 100 can be synchronized with a global coordinate system. The modules 100 can determine their orientation within the global coordinate system. The modules 100 can utilize the global coordinate system for accuracy. One or more modules 100 can determine their orientation relative to a coordinate system including the anterior pelvic plane. One or more modules 100 can determine their orientation relative to a coordinate system including a calibrated plane. One or more modules 100 can determine their orientation relative to a coordinate system including a plane approximating the anterior pelvic plane. One or more modules 100 can determine their orientation relative to a coordinate system including a vertical plane. One or more modules 100 can determine their orientation relative to a coordinate system including a horizontal plane. One or more modules 100 can determine their orientation relative to a coordinate system including the axis of gravity. One or more modules 100 can determine their orientation relative to a coordinate system including an origin. One or more modules 100 can determine their orientation relative to a coordinate system for a standing lateral radiograph or x-ray. One or more modules 100 may determine an orientation relative to a predetermined frame of reference.

[0061] The output of module 100 can be correlated to a reference frame used for navigation. The output of module 100 can be correlated to a reference frame used for cup placement. The measurements of module 100 can be displayed. The measurements of module 100 can be displayed in the same coordinate system in which the angle for anteversion is displayed. The measurements of module 100 can be displayed in the same coordinate system in which the angle of pelvic tilt is displayed. The measurements of module 100 can be correlated to a coordinate system by an algorithm. The measurements of module 100 can be correlated to a coordinate system determined by point registration. The measurements of module 100 can be correlated to a coordinate system determined by table registration.

[0062] Power supply 124 may include one or more power sources configured to provide power to electronic control unit 120. In some embodiments, power supply 124 includes one or more rechargeable or replaceable batteries. In some embodiments, power supply 124 includes one or more capacitive storage devices, such as one or more capacitors or ultracapacitors. In some embodiments, power may be provided by other wired and / or wireless power sources. Electronic control unit 120 may be configured to monitor battery levels if a battery is used for power supply 124. Monitoring battery levels can advantageously provide advance warning of power loss. In certain embodiments, module 100 may include a timer configured to cause module 100 to temporarily power off after a predetermined period of inactivity and / or to permanently power off after a predetermined time period has expired.

[0063] The module 100 may include one or more circuit boards and / or other circuits that may be installed within the module 100. The mounting of the one or more sensors 122 may allow the one or more sensors 122 to operate in a region of maximum or optimal sensitivity, accuracy, and / or resolution. A particular mounting offset angle may be selected based on the range of motion of the module 100 during particular expected movements of the patient.

[0064] In one embodiment, the electronic control unit 120 can convert the analog voltage output signals of the one or more sensors 122 into angle measurements for presentation on the external output device 130. Each of the steps can be implemented using hardware and / or software. For each axis of rotation (e.g., pitch and roll) measured, the one or more sensors 122 can continuously output an analog voltage signal. The signal conditioning circuitry of the module 100 can filter the analog output voltage signal (e.g., with a low-pass filter) to remove noise from the signal. The signal conditioning circuitry can amplify or boost the output voltage signal, for example, via a gain circuit. The ADC can convert the continuous analog voltage signal into a discrete digital sequence of data samples, or voltage counts. In one embodiment, the ADC can sample the analog voltage signal once every 2 milliseconds, although other sampling rates are possible. The ADC can have a 12-bit resolution, providing 4096 individual voltage counts.

[0065] In one embodiment, electronic control unit 120 can generate appropriate data points that are converted to angle measurements. Electronic control unit 120 can apply a median filter to the sampled data to eliminate outliers in the data. The output of the median filter can then be fed into a moving average filter. The moving average filter can be used to stabilize the data that is converted to angle measurements. Electronic control unit 120 can perform one or more steps using a finite impulse response ("FIR") or infinite impulse response ("IIR") filter.

[0066] In one embodiment, the electronic control unit 120 can convert the voltage count data to an angle measurement in degrees. When performing the conversion, the electronic control unit 120 can be configured to apply a calibration conversion algorithm. The calibration conversion can be configured to account for unit-to-unit variations in component and sensor placement. A calibration routine can be performed for each axis monitored by one or more sensors 122. The calibration conversion can include removing mechanical or electrical misalignments and applying appropriate gain calibrations for positive or negative slopes. In one embodiment, the electronic control unit 120 can transmit the angle measurement to an external output device 130. In one embodiment, the electronic control unit 120 can transmit raw data from one or more sensors 122 to the external output device 130. In one embodiment, the electronic control unit 120 can transmit analog voltage output signals from one or more sensors 122 to the external output device 130.

[0067] In one embodiment, the electronic control unit 120 may comprise a processing unit configured to perform one or more of the following functions: The electronic control unit 120 may collect measurements from one or more sensors 122 of one or more modules 100; The electronic control unit 120 may accumulate or consolidate data; The electronic control unit 120 may perform calculations to convert measurements from one or more sensors 122 into kinematic information; The kinematic information may relate to pelvic mobility; The kinematic information may relate to patient positioning; The kinematic information may be collected during various patient movements, such as sitting, leaning, or standing; The module 100 may pre-operatively track pelvic orientation when the patient is sitting; The module 100 may track dynamic and static pelvic orientation.

[0068] The external output device 130 can receive digital signals. As described herein, one or more accelerometers can output digital signals through standard digital interfaces, such as I2C and SPI, among others. The external output device 130 can receive digital output signals from the accelerometers. In some embodiments, the external output device 130 only receives signals. In some embodiments, the external output device 130 can send and receive signals. The external output device 130 can include one or more computers, tablets, and / or smartphones. The external output device 130 can include some of the capabilities of the electronic control unit 120 described herein. The external output device 130 can implement any of the capabilities of the electronic control unit 120. In some embodiments, the external output device 130 can convert analog voltage output signals of one or more sensors 122 into angle measurements for presentation on the external output device 130. In some embodiments, the external output device 130 can generate appropriate data points that are converted into angle measurements. In some embodiments, the external output device 130 can convert voltage count data into angle measurements in degrees.

[0069] In some embodiments, the external output device 130 can transmit kinematic data. In some embodiments, the external output device 130 can receive kinematic data. In some embodiments, the external output device 130 can transmit or receive algorithm data. The external output device 130 can communicate with the external storage device 128 to read and / or save data. The external output device 130 can communicate with the external storage device 128 to read program instructions for software and / or hardware. The external storage device 128 can comprise a storage device for storing information. The external storage device 128 can be a server. The external output device 130 can communicate with the server. The external output device 130 has the ability to transmit and / or receive algorithm data and kinematic data to the server.

[0070] The external output device 130 can display data from the module 100. The external output device 130 can display pelvic mobility data. The external output device 130 can display the position or orientation of a portion of the patient's anatomy. The external output device 130 can display a range of motion data. The external output device 130 can display data from one or more modules 100. The external output device 130 can display data in real time. The external output device 130 can control the operation of the module 100. The external output device 130 can turn on the module 100. The external output device 130 can determine when to collect data from the module 100, such as start and stop data collection. The external output device 130 can collect and / or store data in an application or app installed on the external output device 130. The external output device 130 can transmit data to one or more additional devices, such as the external storage device 128. The external output device 130 can include a light indicator. The light indicator can provide classification information about the patient. The light indicators can be red and green lights. A green light can indicate that the patient has normal mobility. A red light can indicate that the patient has abnormal mobility. A green light can indicate that the population average target angle is appropriate for the patient. A red light can indicate that the population average target angle is not appropriate for the patient. Data from module 100 can have inherent value regardless of whether a surgical procedure is performed. Module 100 can provide data commensurate with mobility and provide a wealth of kinematic data about the patient. Module 100 can provide data to the cloud. The data can be stored. The data can be compared to previous or subsequent data. The patient can be tracked over time. Module 100 can provide data for use during surgery.

[0071] The external output device 130 can compare the kinematic information to a target or population average kinematic information. Values ​​based on the output of one or more sensors 122 indicating kinematics can be compared to population average kinematic data. These population average kinematic data can be based on published averages for healthy patients. The external output device 130 can transmit a patient-specific output corresponding to the kinematic information. The patient-specific output can be a suggestion to the surgeon. The patient-specific output can be a suggestion for adjusting the anteversion angle. The patient-specific output can be a suggestion for adjusting the abduction angle. The patient-specific output can be a set of suggested patient-specific target angles. The patient-specific output can be a suggested adjustment to the population average target angle. The patient-specific output can be a suggestion for increasing or decreasing the anteversion angle. The patient-specific output can be a suggestion for utilizing a particular type of implant, such as a dual mobility implant. The patient-specific output can be raw data analyzed and utilized by the surgeon. The patient-specific output can be a graph comparing the patient to the population average. The patient-specific output can take any form that is usable by the surgeon.

[0072] 3A-3C show perspective views of the module 100 coupled to a patient. FIGS. 3A-3C illustrate placement of the module 100 on the sacrum, on the spine, and on the ASIS point. In one embodiment, the sacrum includes a location on a bony prominence that can be identified by palpation of the skin overlying the sacrum. In one embodiment, the module is positioned on the patient's skin overlying the underlying anatomy. The module 100 may be positioned adjacent to, near, on top of, or overlying an anatomical landmark, including the ASIS point or the pubic bone. In one embodiment, the mobility assessment may include pre-operative activity. In one embodiment, positioning the module 100 does not involve an incision to position the module 100. Other combinations and positions of the module 100 are contemplated. FIGS. 3A-3C illustrate placement of the module 100 on the femur, for example, as a band around the femur. In one embodiment, the module 100 is coupled to a garment configured to be worn by the patient. One or more modules 100 are placed on various parts of the body, such as the sacrum, femur, and other locations, such as the ASIS point, spine, or other palpable locations on the body. In one method, one or more modules 100 are placed on the lower back, upper back, and neck. The modules 100, as described herein, can be used in an office setting during a pre-operative visit.

[0073] In one method, module 100 is deployed by a physician. Patient movements can be tracked in the physician's office. The patient can move in a predetermined manner under the physician's direction and supervision. As examples, the patient can be asked to sit and stand. The patient can be asked to perform repetitive exercises. The patient can move through a range of motion. The patient can be asked to maintain a specific posture or position. Module 100 can record movements over a period of time. Module 100 can record movements when commanded, for example, by use of a start / stop interface.

[0074] In some methods, the module 100 can be used in a home setting. In some methods, use in an office setting or a home setting is determined by a physician. Patient movements can be tracked in the patient's home. The patient can move freely during normal activities. For example, the patient can sit, stand, and lean at various angles during the patient's activities. The patient can move through a range of motion. The patient may repeat movements, such as sitting repeatedly. The patient can move through a range of motion. The patient can maintain a posture or position during normal activities. The module 100 can record movements over a period of time. The module 100 can record movements sporadically over a day, week, or month. The module 100 can record movements when movements are detected. The module 100 can record movements when commanded, for example, by use of a start / stop interface.

[0075] An external output device 130 can receive signals from the module 100 in a home setting. As described herein, one or more accelerometers can output signals through a standard digital interface. The external output device 130 can include one or more computers, tablets, and / or smartphones of the patient. In one embodiment, the patient interacts with an app on the smartphone or tablet.

[0076] The patient's smartphone or tablet can be considered the external output device 130 or one of the external output devices 130 in the system. The patient can interact with the external output device 130 to identify an activity to be performed, such as sitting or standing. The patient can interact with the external output device 130 to identify an activity during a time span. The patient can interact with the external output device 130 to turn the module 100 on or off. The patient can interact with the external output device 130 to set a time period for recording movements. The external output device 130 can include instructions or cues for the patient. The external output device 130 can provide instructions on the types of movements that need to be collected.

[0077] The patient's device can transmit information to a physician for pre-operative treatment. The patient's device can transmit information to a surgeon for surgical treatment. The physician can have an external output device 130 to read information from the module 100. The surgeon can have an external output device 130 to read information from the module 100. One or more external output devices 130 can transmit or receive information to any of the components described herein. One or more external output devices 130 can transmit or receive information to a server.

[0078] FIG. 4 shows a diagram of one or more modules 100 in communication with an external output device 130. One or more modules 100 may be placed on a patient. One or more modules 100 may be in communication with the external output device 130. One or more sensors 122 may provide dynamic data to the external output device 130 directly or indirectly through the electronic control unit 120. The external output device 130 may display one or more values ​​related to pelvic mobility. The external output device 130 may display one or more values ​​related to the position or orientation of the patient's anatomy. The external output device 130 may display sacral tilt. The external output device 130 may display lateral pelvic tilt. The external output device 130 may display a value related to baseline tilt. The external output device 130 may display a graphical depiction of pelvic mobility.

[0079] The external output device 130 may comprise any graphical interface. The external output device 130 may comprise a touchscreen. The external output device 130 may comprise a display. The external output device 130 may comprise a screen. The external output device 130 may comprise one or more digital buttons. The external output device 130 may comprise one or more icons. The external output device 130 may include a graphical representation of an anatomy. The external output device 130 may include a graphical representation of a spine. The external output device 130 may include a graphical representation of a pelvis. The external output device 130 may include a graphical representation of an upper extremity. The external output device 130 may include a graphical representation of a lower back. The external output device 130 may include a graphical representation of any part of an anatomy. The external output device 130 may include a graphical representation of the location of the module 100. The external output device 130 may include a graphical representation of one or more anatomical angles. The external output device 130 may include a graphical representation of one or more anatomical axes. The external output device 130 may include a user interface for starting a measurement, such as a touchable button or icon. The external output device 130 may include a user interface for stopping a measurement, such as a touchable button or icon. The external output device 130 may include a user interface for zeroing measurements of one or more modules 100. The external output device 130 may include a user interface for changing menus or switching between menus. The external output device 130 may include a display for one or more measurements. The external output device 130 may include a display for standing measurements. The external output device 130 may include a display for sitting measurements. The external output device 130 may include a display for real-time measurements.

[0080] The external output device 130 may be configured to display one or more on-screen illustrations. The on-screen illustrations may include graphical images or icons. The external output device 130 may be configured to display images of instructions, such as illustrated steps of a surgical procedure. The external output device 130 may be configured to display visual indicators of orientation information received from the module 100. The external output device 130 may be configured to display the degree of rotation of the module 100 relative to one or more planes. The external output device 130 may be configured to display either a positive or negative indicator to indicate the direction of rotation from a reference plane. The external output device 130 may be configured to display interactive indicators to assist a user in maintaining a specific orientation of the module 100. The external output device 130 may be configured to display alphanumeric characters or symbols. The external output device 130 may be configured to display directional arrows. While FIG. 4 shows an example graphical user interface for the external output device 130, other graphical user interfaces are contemplated.

[0081] The external output device 130 can display suggestions to the surgeon. The suggestions can include raw kinematic data from the patient. The suggestions can include a list of patient characteristics. The suggestions can include suggestions for changing the target angle to a patient-specific angle.

[0082] 5A-5B illustrate a pre-operative method. Using module 100, patient mobility can be determined based on a wide variety of motions. The user moves through a wide range of motions, such as standing, sitting, and leaning forward. In one method, data is captured and processed to determine pelvic mobility and / or other kinematic data. Based on the personalized data from the patient, system 10 can provide recommendations to the surgeon. In one method, system 10 can provide recommendations to adjust one or more of the target abduction angle and target anteversion angle for a total hip replacement. In one method, system 10 can provide recommendations for whether to perform a surgical procedure. In one method, system 10 can provide recommendations for implant selection.

[0083] The table below provides an example of guidance provided to the surgeon. The guidance can facilitate the surgeon's selection of target angles. Based on the data provided, the surgeon can vary the anteversion and / or abduction angles. In some methods, the patient can move between sitting and standing. The system 10 can compare the patient's sitting and standing characteristics. The system 10 can compare the patient's measured changes in standing anteversion, sitting anteversion, and functional anteversion to population-based averages. In some embodiments, the system 10 adjusts for the population-based averages and outputs patient-specific target angles as suggestions to the surgeon.

[0084] In one embodiment, the system 10 can provide suggestions for adjusting the angle based on a comparison of the patient's sitting and standing characteristics. The system 10 can provide suggestions, such as decreasing anteversion, increasing anteversion, or no change in anteversion from a population average. These suggestions can be displayed on an external output device 130. These suggestions can be transmitted to an external storage device 128, such as a server. These suggestions can be saved for use during the surgical procedure. These suggestions can be used when planning a surgery.

[0085] [Table 1]

[0086] In one method, the system 10, including the module 100 and the external output device 130, can generate an output that indicates a patient's standing anteversion based on measurements from the module 100. For example, the external output device can display a standing anteversion angle of 3 degrees. This measurement can suggest a neutral standing pelvis. The system 10 can provide an indication of patient-specific standing data. The system 10, including the module 100 and the external output device 130, can generate an output that indicates a patient's sitting anteversion based on measurements from the module 100. For example, the external output device can display a sitting anteversion angle of -17 degrees. This measurement can suggest a sitting orientation with sufficient clearance to avoid collisions. The system 10 can provide an indication of patient-specific sitting data. The system 10, including the module 100 and the external output device 130, can generate an output that indicates a patient's mobility. For example, the external output device can display a mobility indication over a 20-degree range. This measurement can suggest a standard range of movement. The system 10 can provide an indication of patient-specific mobility data. One or more of these outputs can be utilized by the surgeon to determine a patient-specific target anteversion for optimal stability.

[0087] For another patient, the system 10 including the module 100 and the external output device 130 can output a standing anteversion of -1 degree. This measurement can suggest a neutral standing pelvis. The system 10 including the module 100 and the external output device 130 can output a sitting anteversion of -10 degrees. This measurement can suggest a sitting orientation with insufficient clearance to avoid impingement. The system 10 including the module 100 and the external output device 130 can output a range of motion of 9 degrees. This measurement can suggest a reduced range of motion. One or more of these outputs can be used by the surgeon to determine whether to increase the target anteversion to avoid impingement and improve posterior stability when sitting.

[0088] 6 illustrates an embodiment of a surgical workflow. Module 100 can be integrated into a pre-operative workflow. The pre-operative workflow can be separate in time and space from the surgical workflow. Module 100 can be easily integrated into current workflows. Module 100 can facilitate pre-operative goal planning as described herein.

[0089] In one method of use, a patient may undergo a pre-operative visit as shown in FIG. 6. One or more modules 100 may be attached to the patient's body. In one method of use, a module 100 is placed on the sacrum. In one method of use, at least one module 100 is placed on the sacrum. In one method of use, a module 100 is placed on the coccyx. In one method of use, at least one module 100 is placed on the tailbone. In one method of use, a module 100 is placed on the ilium. In one method of use, a module 100 is placed on the iliac crest. In one method of use, a module 100 is placed on the iliac spine. In one method of use, a module 100 is placed on the rim of the acetabulum. In one method of use, a module 100 is placed on the ischium. In one method of use, a module 100 is placed on the pubic bone. In one method of use, a module 100 is placed on the pubic eminence. In one method of use, a module 100 is placed on the pubic symphysis. In one method of use, at least one module 100 must be placed in the pelvis.

[0090] In some methods, the module 100 may be placed at one of the ASIS points. The module 100 at the sacrum may be used in combination with the module 100 at one of the ASIS points. In some methods, the module 100 may be placed at both ASIS points. The module 100 at the sacrum may be used in combination with the module 100 at both of the ASIS points. In some methods, the module 100 may be placed at one of the PSIS points. The module 100 at the sacrum may be used in combination with the module 100 at one of the PSIS points. In some methods, the module 100 may be placed at both PSIS points. The module 100 at the sacrum may be used in combination with the module 100 at both of the PSIS points.

[0091] In some methods, the module 100 may be placed on one of the femurs. A module 100 on the sacrum may be used in combination with a module 100 on one of the femurs. In some methods, the module 100 may be placed on both femurs. A module 100 on the sacrum may be used in combination with a module 100 on both femurs. In some methods, the module 100 may be placed on one or both tibias. In some methods, the module 100 may be placed on one or both patellas. In some methods, the module 100 may be placed on one or both fibulae. In some methods, the module 100 may be placed on one or both feet. In some methods, the module 100 may be placed on one or both tarsals. In some methods, the module 100 may be placed on one or both calcaneus. In some methods, the module 100 may be placed on one or both metatarsals. In some methods, the module 100 may be placed in areas that can be placed on one or both legs. The module 100 in the sacrum can be used in combination with modules 100 in one or both legs.

[0092] In some methods, the module 100 is placed on the spine. The module 100 on the sacrum can be used in conjunction with the module 100 on the spine. In some methods, the module 100 is placed on the lower back. The module 100 on the sacrum can be used in conjunction with the module 100 on the lower back. In some methods, the module 100 is placed on the upper back. The module 100 on the sacrum can be used in conjunction with the module 100 on the upper back. In some methods, the module 100 is placed on the neck. The module 100 on the sacrum can be used in conjunction with the module 100 on the neck. In some methods, the module 100 is placed on one or more bones in the chest. In some methods, the module 100 is placed on one or more ribs. In some methods, the module 100 is placed on a portion of the rib cage. In some methods, the module 100 is placed on the sternum. The module 100 on the sacrum can be used in combination with the module 100 on the sternum. In some methods, the module 100 is placed on the clavicle. In some methods, modules 100 are placed in one or more vertebrae (e.g., cervical, thoracic, lumbar, sacral, coccygeal, and any combination of vertebrae). Module 100 in the sacrum can be used in combination with modules 100 in one or more vertebrae.

[0093] In some methods, modules 100 are placed at any two locations on the body. In some methods, modules 100 are placed at one or more locations on the body (e.g., 1 location, 2 locations, 3 locations, 4 locations, 5 locations, 6 locations, 7 locations, 8 locations, 9 locations, 10 locations, or a range of any of the foregoing values). In some methods, modules 100 are placed at one or more contralateral locations on the body. In some methods, modules 100 are placed at one or more symmetrical locations. In some methods involving two or more modules 100, two or more modules 100 can be used in combination. In some methods involving two or more modules 100, two or more modules 100 can collect measurements simultaneously. In some methods involving two or more modules 100, two or more modules 100 can collect measurements separately. In some methods, modules 100 are positioned on different parts of the body.

[0094] In some methods, module 100 may be placed at one or more palpable locations. In some methods, module 100 may be placed at the junction of the neck and rib cage. In some methods, module 100 may be placed on any surface of the patient's skin. In some methods, module 100 may be placed on any surface of the patient's skin overlying a bone. Module 100 may be coupled to at least one anatomical region. In some methods of use, module 100 is coupled to at least one anatomical region with some soft tissue. The soft tissue may move relative to the underlying bone. Module 100 may be configured to track the underlying bone.

[0095] One or more modules 100 can output data when the patient stands. One or more modules 100 can output data when the patient sits. One or more modules 100 can output data when the patient is in any position or during any movement. In an embodiment, the module 100 includes one or more sensors 122 that measure position, orientation, and / or movement. Data from the one or more sensors 122 can be captured. Data from the one or more sensors 122 can be processed. Standing data can be related to sitting data. A range of motion data can be accumulated. The range of motion data can be related to a patient-specific target angle. In some methods, the patient-specific target angle can be part of a pre-operative plan to determine the patient-specific target angle.

[0096] In one embodiment, one or more modules 100 are utilized. The one or more modules 100 can measure pelvic mobility. This pelvic mobility can be used in surgical planning. The one or more modules 100 can collect dynamic mobility measurements. A patient can move in various ways, such as standing, sitting, leaning, lifting one leg, lifting the other leg, squatting, or other movements. The one or more modules 100 can collect dynamic mobility measurements during movement by the patient. The one or more modules 100 can collect dynamic mobility along a trajectory of movement from sitting to standing. The one or more modules 100 can transmit data to an external output device 130. The module 100 can interact with the external output device 130, such as a smartphone with an app. These steps can be completed in an office or home setting. These steps can be completed pre-operatively.

[0097] In some embodiments, the surgeon can review data from module 100. In some embodiments, the surgeon can review data from module 100 on external output device 130. In some embodiments, external output device 130 can be in communication with external storage 128. In some embodiments, the surgeon can review data from module 100 on external storage 128. In some embodiments, the surgeon can review data from module 100 on external output device 130, which reads information from external storage. In some embodiments, external output device 130 and / or external storage 128 can be in communication with one or more operating devices. In some embodiments, the surgeon can review data from module 100 on surgical orientation device 172. Surgical orientation device 172 can be used during a surgical procedure, such as a total hip replacement. In some embodiments, surgical orientation device 172 can receive patient-specific data obtained from one or more modules 100.

[0098] The surgeon can determine a target cup angle based at least in part on data from one or more modules 100. The surgeon can use their own judgment in interpreting the patient-specific data. The surgeon can accept a suggestion from system 10. The surgeon can reject a suggestion from system 10. The surgeon can modify a suggestion from system 10. Once the target angle is determined by the surgeon, the target angle can be an input to surgical orientation device 172. Surgical orientation device 172 can facilitate guiding the cup to the target angle.

[0099] In one embodiment, the patient-specific target angle may be displayed on the surgical orientation device 172 for use in the operating room. In one embodiment, the module 100 and data from the module 100 may be incorporated without modification into current surgical workflows.

[0100] In one embodiment, module 100 is utilized in a surgical setting. Module 100 can provide data regarding patient positioning. Module 100 can determine whether a hip joint is properly positioned. Module 100 can be placed at an anatomical location. Two or more modules 100 can be placed at an anatomical location. In one method, module 100 can determine whether an ASIS line is horizontal. In one method, module 100 can determine whether an ASIS line is vertical. In one method, module 100 can determine whether a pelvis is vertical. In one method, module 100 can determine whether a pelvis is level. In one method, module 100 can determine whether a patient is properly positioned for an anterior approach. In one method, module 100 can determine whether a patient is properly positioned for a posterior approach.

[0101] In one embodiment, module 100 includes one or more sensors 122 that measure position, orientation, and / or movement during a surgical procedure. Data from the one or more sensors 122 may be captured. Data from the one or more sensors 122 may be processed. The patient may be adjusted to achieve proper positioning. The patient's anatomy may be tracked during a surgical procedure. Module 100 may track pelvic rotation. Module 100 may track pelvic orientation. Module 100 may track anatomy alignment during a surgical procedure. Module 100 may ensure that the ASIS line is aligned with vertical or horizontal, depending on the surgeon's approach.

[0102] The module 100 can provide several advantages. The module 100 can enable the surgeon to personalize or adjust the preoperative plan. The module 100 can enable the surgeon to improve the preoperative plan based on the patient's specific pelvic mobility. The module 100 can facilitate personalized cup placement. The personalized target angle of cup placement can be more effective and result in better clinical outcomes. The module 100 can account for patient-specific pelvic tilt. The module 100 can account for patient-specific range of motion. The surgeon can consider patient-specific activities of daily living when determining the patient-specific target angle. The surgeon can consider changes from supine or lateral decubitus to weight-bearing or standing when determining the patient-specific target angle. The surgeon can consider adjustments to match functional anteversion when determining the patient-specific target angle.

[0103] The module 100 can be used to provide kinematic or other patient-specific data to the surgeon. The surgeon can use this data to determine a patient-specific target angle. The module 100 can be used to modify the target anteversion angle. The module 100 can be used to determine a patient-specific anteversion angle. The module 100 can be used to determine a target functional anteversion. In certain embodiments, the module 100 can advantageously prevent or reduce instability. Another advantage is that the module 100 can prevent or reduce dislocation. Yet another advantage is that the module 100 can prevent or reduce impingement. Guidelines for cup placement can include a general (Lewinnek) safe zone. This safe zone can be suboptimal for cup placement guidance. The module 100 can improve this safe zone by providing suggestions to adjust the target angle based on preoperative measurements. The surgeon can accept, reject, or modify any suggestions made by the system 10.

[0104] The module 100 may be advantageously used to classify patients. Pelvic tilt is relevant to total hip replacement surgery. There is a need to identify patients who are suitable candidates for typical total hip replacement surgery and for various implant types, such as dual mobility. Pelvic tilt is relevant to determining whether the target cup angle should be adjusted. Patient anatomy can have various deformities that affect pelvic tilt. Patients can have spinal deformities, such as sagittal spinal deformities, that affect pelvic tilt. Previous spinal surgery, such as fusion, can affect pelvic mobility. The probability of dislocation is higher for patients with previous spinal surgery. Alignment between the spine and pelvis can affect the target anteversion angle. There is a need to determine patient-specific target angles to improve clinical outcomes.

[0105] Module 100 can provide information about patient characteristics. These characteristics can be used to classify patients. These characteristics can be used to modify the surgical plan, for example, by determining whether to change the average target angle for the population. These characteristics can be used to determine whether the patient is a candidate for surgery. These characteristics can be used to determine what type of surgery to perform.

[0106] These characteristics can be used to determine which type of implant to use. Module 100 can provide information about whether to use a dual-mobility implant. In some uses, a dual-mobility hip replacement reduces the risk of dislocation for a particular patient. Module 100 can provide information useful in pre-operatively determining which patients would benefit from a dual-mobility implant. A dual-mobility implant includes a femoral head that is constrained but movable within a liner, which is constrained but movable within an acetabular shell. Module 100 can determine the patient's mobility characteristics, which can be used by the surgeon to select an implant. Module 100 can determine whether the patient has abnormal or normal mobility. These characteristics can be used to determine whether to use a patient-specific implant. Information from module 100 can help assess the risks of the surgery, such as the risk of dislocation. These characteristics can be used to determine which type of tool or surgical instrument to use. These characteristics can be used to determine whether to use a patient-specific tool.

[0107] In some embodiments, module 100 can be used in combination with radiographs or other imaging techniques. In one method of use, a patient undergoes radiographic evaluation. Radiographic evaluation can provide a snapshot of the pelvic range of motion using various positions. Radiographs can be taken while the patient is standing, sitting, and / or leaning. In some methods, radiographic evaluations can have limited effectiveness. These evaluations involve tedious, manual processes to position the patient. Radiographic evaluations can require large, expensive equipment that is difficult to access. Radiographs or other imaging techniques also pose risks to patients due to increased radiation exposure. These evaluations only provide a snapshot or still image of the patient. In some methods, these images provide less useful information than dynamic measurements. Module 100 can enhance pre-operative radiographic data because the sensor data is dynamic across a continuous range of motion.

[0108] In some embodiments, module 100 can be used in place of imaging techniques such as x-rays. Module 100 can provide dynamic measurements of pelvic mobility. Module 100 can provide measurements of patient positioning. In some embodiments, the target angle is determined without the need for pre-operative x-rays of patient mobility. Rather, the surgeon can rely on the range of motion detected by module 100 to determine the patient-specific target angle.

[0109] Module 100 may have a broad purpose to determine patient characteristics. Module 100 may determine mobility. Module 100 may determine patient positioning. Module 100 may provide static or dynamic information specific to the patient being monitored. Module 100 may have a narrower purpose to provide a patient assessment to the surgeon. The assessment may relate to patient-specific mobility. The assessment may relate to whether the patient has normal or abnormal mobility. The assessment may relate to whether the patient is a good candidate for a particular type of surgery or implant. The assessment may provide data in addition to or instead of traditional imaging techniques. With this data, the surgeon can determine the surgical plan, such as determining patient-specific target angles. Module 100 is a useful tool for providing data to the surgeon.

[0110] The module 100 can be used in combination with intraoperative guidance. The module 100 can improve the precision and accuracy of intraoperative guidance. In one embodiment, the module 100 can be used for intelligent targeting of the anteversion angle, which is personalized. The module 100 can provide preoperative data to the surgeon to better predict the target abduction and anteversion angles for cup placement. The ultimate goal is to improve patient outcomes that can be influenced by cup placement and targeting.

[0111] Module 100 can be used for targeted surgical planning. Module 100 can be used to track weight loss before surgery. Module 100 can be used to track muscle tone before surgery. Module 100 can be used to determine readiness for surgery. Module 100 can be used for user compliance with pre-operative programs. Module 100 can be used for communications. Module 100 can be used for smart, personalized, economical, and connected care. Module 100 can be used to reduce cost and complexity.

[0112] B. Hip replacement for anterior and posterior approaches 1. Hip joint guidance system Discussed below are various systems and methods that can be used to improve patient outcomes by increasing the likelihood of proper placement of a medical prosthesis. These systems may focus on inertial guidance techniques to establish a reference plane. These systems may focus on inertial guidance techniques to guide the medical prosthesis relative to the reference plane. In some methods, any intraoperative guidance system may be utilized. The intraoperative guidance system may be capable of guiding to a determined target cup angle. In some methods, the target cup angle may be determined based at least in part on data from one or more modules 100. The method may utilize one or more of the steps described below. In some methods, the module 100 is utilized for purposes other than for use in guidance.

[0113] The system and method may include a primary handheld electronic surgical orientation device with a user interface and a set of inertial sensors, and a secondary electronic orientation device with a second set of inertial sensors and a fixture for connecting the orientation device to the pelvis. The electronic orientation device can establish a reference plane before the cup is placed. The secondary electronic orientation device may be connected to a cup insertion device to monitor the abduction and anteversion angles relative to this reference plane during cup placement. Features of the system are described herein.

[0114] Figure 7 illustrates a hip guide system 600 adapted to guide a hip procedure relative to anatomical landmarks. The system 600 is shown attached to a pelvis, which is shown as a rectangle for simplicity in Figure 7. The system 600 may be attached to the pelvis for a posterior approach as described herein. The system 600 may be attached to the pelvis for an anterior approach as described herein.

[0115] System 600 may include a fixed base 602, a first assembly 604, and a second assembly 606. The first assembly 604 is rigidly connected to the hip joint or pelvis in the illustrated configuration so that movement of the pelvis causes corresponding movement of sensors in the first assembly 604, as discussed herein. By sensing this movement, system 600 can eliminate patient movement as a source of error in guidance. The second assembly 606 provides a full range of controlled movement and sensors that can cooperate with the sensors in the first assembly 604 to track movement.

[0116] The sensors in the assemblies 604, 606 preferably communicate data between themselves and, optionally, with external devices, including the module 100, an external output device 130, such as a computer, tablet, and / or smartphone, and an external display. The assemblies 604, 606, the module 100, and the external output device 130 can communicate data wirelessly using Bluetooth, Wi-Fi, or other standard wireless telemetry protocols. The system 600 may include one or more fixation pins 610, 612. The system 600 may further include a surgical orientation device 172 and an orientation sensing device 204, as described herein. A patient-specific target angle determined by the surgeon may be input to the surgical orientation device 172. The surgical orientation device 172 and the orientation sensing device 204 can facilitate guiding the acetabular cup to the desired target angle.

[0117] The surgical orientation device 172 detects the orientation and rotation of the device 172 relative to a reference frame. The surgical orientation device 172 preferably includes at least one source-less inertial sensor, such as an accelerometer, a gyroscope, or a combination of these and other sensors. In one embodiment, the surgical orientation device 172 includes a three-axis accelerometer for detecting orientation relative to gravity and multiple gyroscopes for detecting rotation. Other sensors may be used in various configurations. Examples of specific sensor combinations include Analog Devices' ADIS 16445 and Invensense's MPU-6050 or MPU-9150, among others. In one embodiment, the surgical orientation device 172 can be disposable, and the sensor can be an inexpensive sensor. In one embodiment, the surgical orientation device 172 is disposable. In one embodiment, the surgical orientation device 172 is reusable.

[0118] The surgical orientation device 172 may include one or more sensors that together form an inertial measurement unit (IMU). In some embodiments, the IMU may include a first sensor for determining acceleration and a second sensor for determining gyroscopic position. As described herein, the first sensor may be an accelerometer and the second sensor may be a gyroscopic sensor. In some embodiments, the sensors may include a three-axis gyroscopic sensor and a three-axis accelerometer sensor. The surgical orientation device 172 may include a transceiver for transmitting data or receiving data from one or more sensors of the system 600, such as one or more sensors of the orientation sensing device 204. The surgical orientation device 172 may include a transceiver for transmitting data or receiving data from the module 100 and the external output device 130. Information received from the orientation sensing device 204 may be fed into an input port, or alternatively, the electronic control unit itself may receive the information (e.g., wirelessly). Information from the orientation sensing device 204 may correspond, for example, to the position and / or orientation of the orientation sensing device 204 and may be used by the surgical orientation device 172 to determine the collective or overall position and / or orientation of the surgical orientation device 172. Information from the module 100 and / or the external output device 130 may correspond, for example, to pelvic mobility and may be used by the surgical orientation device 172 to guide to a patient-specific target angle.

[0119] The system 600 may include a second assembly 606. The second assembly 606 may include a dock 662 sized to accept passage of a probe 678. The probe 678 may have a distal tip 680 designed to touch a point or location, as described herein. The distal tip 680 may be straight, as shown. In other embodiments, the distal tip 680 is beveled or curved. The probe 678 may be movably coupled to the dock 662. The distal tip 680 of the probe 678 may pivot or rotate to contact an anatomical landmark. The probe 678 may slide relative to the dock 662 to different translational positions relative to the attachment positions of the fixation pins 610, 612. The sliding ability of the probe 678 within the dock 662 may allow the distal tip 680 to be moved to reach points or anatomical landmarks that are in the same plane as the probe 678 but that are closer or farther away than the distal tip 680. The second assembly 606 allows a range of motion for the distal end 680 of the probe 678 to facilitate obtaining points that are spaced apart from the attachment locations of the fixed pins 610, 612. The second assembly 606 allows a range of motion for the distal end 680 of the probe 678 to facilitate obtaining multiple landmarks at different distances from the attachment locations of the fixed pins 610, 612. While the probe 678 is shown as an elongated member, other configurations are contemplated. Any indicator may be utilized to establish the orientation or location of the point. In some embodiments, a light or laser may be the indicator for establishing the location and / or orientation of the point. In some embodiments, a camera may be the indicator for establishing the location and / or orientation of the point. In some embodiments, a probe may be the indicator for establishing the location and / or orientation of the point. In some embodiments, a probe with one or more scales or markings may be the indicator for establishing the location and / or orientation of the point. In an embodiment, a probe with a computer readable code, such as a QR code, can be an indicator for establishing the location and / or orientation of the point.

[0120] The orientation sensing device 204 can detect the encirclement and rotation of the probe 678 as described herein. The orientation sensing device 204 preferably comprises at least one sourceless sensor, such as an accelerometer, a gyroscope, or a combination of these and other sensors. In one embodiment, the orientation sensing device 204 comprises a three-axis accelerometer for detecting orientation relative to gravity and multiple gyroscopes for detecting rotation. Other sensors may be used in various calibrations. In one embodiment, the orientation sensing device 204 is reusable.

[0121] In some methods of use or method steps, the orientation sensing device 204 is coupled to the probe 678 such that movement of the probe 678 corresponds to movement of the orientation sensing device 204. In some methods of use or method steps, the orientation sensing device 204 is coupled to a non-movable, stationary portion of the second assembly 606, such as for calibration. In some methods of use or method steps, the orientation sensing device 204 is coupled to a movable portion of the second assembly 606, such as the dock 662. In this position, the orientation sensing device 204 can determine a length measurement or extension of the probe 678. In some embodiments, the probe 678 can include markings or graduations. In some embodiments, the orientation sensing device 204 can include a camera. The camera can capture an image of the markings on the probe 678.

[0122] In one method of use, system 600 includes optical element 174, as shown in FIG. 9 . Optical element 174 can be any device designed to project light, including visible, ultraviolet, or infrared light. Optical element 174 can include one or more lasers, which can be configured to project laser light. Lasers can project light with a very narrow spectrum, such as a single color of light. In some embodiments, optical element 174 is integrated into surgical orientation device 172. In some embodiments, optical element 174 can be a separate component from surgical orientation device 172. Optical element 174 can be positioned beside, adjacent to, or above surgical orientation device 172. A display on surgical orientation device 172 can include instructions related to how to use optical element 174. In some embodiments, optical element 174 can be rotated, pivoted, or moved relative to first assembly 604. The rigidity of the system 600 can fix the position of the optical element 174 once it is moved into position.

[0123] In one method of use, the optical element 174 can be positioned and / or moved to project light onto a selected portion of the anatomy. In one method of use, the optical element 174 can be positioned and / or moved to project light onto a target probe, as described herein. In one method of use, the optical element 174 can be positioned and / or moved to project light onto a sterile wrap, medical drape, bandage, tape, and / or other device.

[0124] The optical element 174 can emit a pattern of light. Examples of a light pattern include one or more lines, one or more points, one or more planes, or one or more shapes. The optical element 174 can be moved until light is projected onto at least one anatomical region. In one method of use, light is projected onto at least one anatomical region with some soft tissue. The soft tissue may move relative to the underlying bone. The surgeon can select a location to illuminate where the skin is near the underlying bone. In one method of use, the optical element 174 can project a pattern onto a portion of the anatomical structure or a target connected to the anatomical structure. The optical element 174 can project one or more points, one or more lines, one or more planes, one or more shapes, one or more colors, and / or one or more patterns. In one embodiment, the projection of light incident on the surface is visible as two intersecting lines, and the pattern may be referred to herein as a crosshair. Optical element 174 may be used to perform one or more methods or method steps.

[0125] 2. Method for the posterior approach FIG. 7 shows a hip joint guidance system 600 that may be adapted to guide a hip joint procedure from a posterior approach.

[0126] In some methods of cup placement in total hip replacement, the tilt and anteversion angles are relative to the anterior pelvic plane (defined as the plane created by the two anterior superior iliac spines (ASIS) and the pubic symphysis). While these anatomical features are visible / palpable while the patient is in the supine position, the majority of total hip replacements are accomplished via a posterolateral approach, with the patient in a deformed lateral position where most of these landmarks are not accessible or visible. Historically, guidance for posterior approach hip replacements has been achieved by first registering the anatomic features of the anterior pelvic plane with the patient in the supine position, and once this plane is registered by the guidance computer, moving the patient to a lateral position to perform the hip surgery, with guidance performed directly relative to the registered anterior pelvic plane. This approach to hip guidance is suboptimal for surgical workflow, as excessive patient movement from the supine to the lateral position consumes more surgeon and staff time, disrupts sterility, and requires re-draping. This is one of the main reasons why hip joint induction has failed to be adopted by most of the market.

[0127] FIG. 8 illustrates an embodiment of patient positioning for a posterior hip approach. Most hip replacement procedures are currently performed from a posterior approach. In this approach, the patient is positioned on their lateral side, with the anterior pelvic plane oriented vertically, e.g., perpendicular to the plane of the table on which the patient is positioned. In a posterior hip approach, the patient can be positioned on their lateral side. In one method of use, the patient can be positioned in a lateral decubitus position. When positioning the patient prior to surgery, the surgeon can align the anterior pelvic landmarks (both the ASIS and the pubic eminence) in a vertical plane parallel to the long edge of the operating table. In one method of use, when positioning the patient prior to surgery, the surgeon can align the anterior pelvic landmarks (both the ASIS and the pubic eminence) in a vertical plane perpendicular to the surface of the table. In one method of use, when positioning the patient prior to surgery, the surgeon can align the anterior pelvic landmarks (both the ASIS and the pubic eminence) in a vertical plane parallel to gravity. In one method of use, when positioning a patient prior to surgery, the surgeon can align the anterior pelvic plane parallel to gravity. In one method of use, when positioning a patient prior to surgery, the surgeon can align the anterior pelvic plane vertical.

[0128] In one method of use, the system 600 calculates the cup angle based on the assumption that the pelvis is correctly positioned. In one method of use, the system 600 calculates the cup angle based on the assumption that the anterior pelvic plane is vertical during the posterior procedure. The surgeon can ensure that the pelvis is securely held by an appropriate positioning device, such as a pegboard or vice-style patient positioner. The surgeon can confirm that the patient is positioned in the proper position for the posterior approach. Correct patient positioning is important for accurate navigation.

[0129] The system 600 may be partially assembled for calibration. In an embodiment, a first assembly 604 may be assembled. The surgical orientation device 172 may be coupled to the first assembly 604. In an embodiment, a second assembly 606 may be assembled. The orientation sensing device 204 may be coupled to the second assembly 606. The orientation sensing device 204 may be coupled to a non-movable portion of the second assembly 606. The orientation sensing device 204 may be fixed in position relative to the surgical orientation device 172. The angle between the orientation sensing device 204 and the surgical orientation device 172 may be fixed. The surgical orientation device 172 and the orientation sensing device 204 may be calibrated.

[0130] The system 600, or a portion thereof, may be attached to the pelvis, as shown in FIG. 9. In one method, the fixation pins 610, 612 are placed on the ipsilateral iliac crest. The surgeon can slide the fixed base 602 over both pins 610, 612. The first assembly 604 may be secured to the fixed base 602. The surgical orientation device 172 may be attached to the first assembly 604, or may be separately coupled once the first assembly 604 is secured. The optical element 174 may be secured to the system 600. In one embodiment, the optical element 174 may be secured to the first assembly 604.

[0131] The surgeon can position the leg on the operating side in a neutral position. The surgeon can align the optical element 174 so that the laser projects a light pattern as shown in FIG. 9 . The surgeon can adjust the optical element 174 to project the light onto an anatomical landmark or target. The method can include marking the light incidence 180. The method can include marking two or more points along the line of light. The method can include drawing a line along the line of light. The method can include capturing an image of the light incidence 180. In some embodiments, the surgeon tracks the light pattern. In some embodiments, the surgeon can mark the femur with bobby marks, pen marks, stitches, or other durable indications. In some embodiments, the surgeon can mark the light incidence 180.

[0132] FIG. 10 illustrates one embodiment of table registration. FIG. 10 is a top view of the patient in a posterior approach lateral decubitus position. The surgeon can confirm that the sagittal plane of the pelvis is the reference position. During patient positioning, the anterior pelvic plane is positioned vertically. The anterior pelvic plane can be defined as the plane created by the two anterior superior iliac spines (ASIS) and the anterior surface of the pubic symphysis. The anterior pelvic plane can be oriented vertically when the patient is in a posterior approach lateral decubitus position. The table plane can be a horizontal plane or a generally horizontal plane.

[0133] During table registration, the probe 678 is coupled to the orientation sensing device 204. In one method of use, the probe 678 and the orientation sensing device 204 are constrained such that movement of the probe 678 causes movement of the orientation sensing device 204. FIG. 10 illustrates the position of the probe 678 for calculating the direction of gravity when the probe 678 is generally horizontal. The probe 678 may be aligned with the long axis of the body. The probe 678 may be held substantially parallel to the plane of the table. In one embodiment, a user may align the probe 678 with the horizontal. The user may visually inspect the probe 678 from one or more locations to confirm alignment with the table plane. As described herein, the probe 678 coupled to the orientation sensing device 204 may be positioned horizontally or substantially horizontally to measure gravity. The probe 678 may be held stationary during table registration.

[0134] 10 shows the probe 678 decoupled from the second assembly 606. In some embodiments, the probe 678 is decoupled from the second assembly 606 during table plane registration. In some embodiments, the probe 678 is coupled from the second assembly 606 during table plane registration. The probe 678 can be coupled to the dock 662 and held in a horizontal position.

[0135] In some embodiments, the position and / or orientation of the orientation sensing device 204 may be recorded by the surgical orientation device 172 when the probe 678 is held horizontally. In some embodiments, gravity measurements are taken when the probe 678 is positioned horizontally. A user can position the probe in an approximately horizontal position by aligning the probe with a horizontal and / or vertical reference plane in the surgical field. A sensor in the orientation sensing device 204 can sense the direction of gravity to provide an estimate of the horizontal and / or vertical axis. In some embodiments, the orientation sensing device 204 and the surgical orientation device 172 can detect the direction of gravity by other methods. In some embodiments, the orientation sensing device 204 is held vertically to sense the direction of gravity. In some embodiments, the orientation sensing device 204 is held at any angle relative to the horizontal. In some embodiments, the orientation sensing device 204 is held at any angle relative to the vertical. A user can enter an input (e.g., by depressing a button on the surgical orientation device 172) to register the table. The user can interact with a user interface on the surgical orientation device 172 to send a signal to the surgical orientation device 172 to capture data from the orientation sensing device 204. The surgical orientation device 172 can indicate that the data has been recorded. In one method of use, table registration can be taken at a point during a procedure. Table registration can be taken during pre-operative calibration. Table registration can be taken during intra-operative calibration. The surgical orientation device 172 can store a table plane and / or a table reference frame.

[0136] Table registration can utilize a measurement of gravity. As described herein, surgical orientation device 172 includes one or more inertial sensors. As described herein, orientation sensing device 204 includes one or more inertial sensors. In some embodiments, inertial data from one or more inertial sensors is used to calculate a vertical plane and / or a horizontal plane. In some embodiments, position and / or orientation data from one or more inertial sensors is used to calculate a table plane or table reference frame. Surgical orientation device 172 and / or orientation sensing device 204 can include an accelerometer that can provide a measurement of the direction of gravity. The accelerometer at rest can measure acceleration due to Earth's gravity. The accelerometer can measure acceleration from gravity either downward or straight up. The accelerometer can generate a vertical vector. The accelerometer can generate a horizontal vector by transforming the vertical vector (e.g., by rotating it 90 degrees). The accelerometer can provide orientation and / or position data so that the table plane is perpendicular to gravity. In certain embodiments, the surgical orientation device 172 and / or the orientation sensing device 204 include sensors to detect the direction of gravity. In certain methods of use, the orientation sensing device 204 and the probe 678 may be positioned in a manner other than horizontal to measure the direction of gravity.

[0137] The surgical orientation device 172 and / or orientation sensing device 204 can provide a reference to zero gravity. Zero gravity, as referenced herein, generally refers to an orientation in which the axis of the sensor is perpendicular to the force of gravity, thereby not subject to angular misalignment, e.g., tilt, pitch, roll, or yaw, relative to the gravity vector. The surgical orientation device 172 can store the zero gravity for calculations related to the table plane. In some methods, the zero gravity is registered once and utilized throughout the procedure. Table registration can include recording a measurement of zero gravity.

[0138] The table's frame of reference may include two orthogonal planes. The two orthogonal planes may include a vertical plane and a horizontal plane. The vertical plane may approximate the anterior pelvic plane. The vertical plane may be recorded and stored by the surgical orientation device 172 and / or the orientation sensing device 204. The horizontal plane may approximate the plane of the table. The horizontal plane may be recorded and stored by the surgical orientation device 172 and / or the orientation sensing device 204.

[0139] The orientation of the vertical plane can be a reference for placement of the cup portion of a hip prosthesis. For example, the abduction and anteversion angles can be calculated relative to the vertical plane. The system 600 can calculate the cup angle relative to the vertical plane based on the assumption that the patient's pelvis is correctly positioned so that the anterior pelvic plane is vertical. In one embodiment, the vertical plane is determined by the surgical orientation device 172 and / or the orientation sensing device 204. In one method of use, the abduction and anteversion angles for cup placement in a total hip replacement can be relative to the vertical plane determined by table registration.

[0140] The surgical orientation device 172 can display information regarding the calculated vertical plane. In one method of use, the abduction and anteversion angles induced during cup placement can be relative to the vertical plane. In one embodiment, the surgical orientation device 172 and / or the orientation sensing device 204 can provide orientation and / or position data relative to the vertical plane.

[0141] In one embodiment, the vertical plane is a substitute for the anterior pelvic plane for a posterior approach. The vertical plane can be determined completely independent of any anatomical landmarks. The vertical plane provides a reference plane that is not affected by pelvic tilt. The vertical plane provides a reference plane that is not affected by errors in landmark registration due to soft tissue.

[0142] As discussed herein, a method of use may include using the probe 678 and the sensor 204 to estimate the horizontal plane of a surgical table on which the patient is resting. In one method of use, the horizontal plane or table plane is calculated based on positioning the probe 678. As discussed herein, a method of use may include using the probe 678 and the sensor 204 to estimate the vertical plane using gravity measurements. The system 600 can establish a frame of reference for guiding cup placement without registering landmarks. In one method of use, the vertical plane is calculated based on gravity measurements. In one method of use, the target cup angle is relative to a vertical plane determined by gravity. In one method of use, the induced cup angle is relative to a vertical plane that approximates the anterior pelvic plane.

[0143] Pre- and / or post-operative images, such as radiographs, are captured in a reference plane similar to the anterior pelvic plane. Table registration can provide a reference plane that approximates the reference plane of the imaging technique. Table registration can provide a reference plane that approximates the anterior pelvic plane.

[0144] The system 600 can measure leg length and / or joint misalignment within an established reference frame. The system 600 can also compare leg length between a patient's two legs. Leg length and / or joint misalignment measurements can be taken before and after cup placement. Measurements can be pre-operative and post-operative. In one method of use, the surgeon can register a point. In one method of use, the surgeon can register only one point on the femur. In one method of use, the surgeon registers only one anatomical landmark during the procedure. The probe 678 can be coupled to the second assembly 606. The orientation sensing device 204 can be coupled to the probe 678 and / or the dock 662. The probe 678 can be immobilized to register a point. Once the tip of the distal end 680 contacts the desired point, the system 600 processes data from one or more sensors in the orientation sensing device 204 and stores the orientation of the sensor.

[0145] In some techniques, table registration is completed before dislocating the hip. In some techniques, the points are registered before dislocating the hip. In some techniques, the light incidence 180 is marked before dislocating the hip. Once registration is complete, the surgeon can proceed to dislocate the hip, resect the femoral head if applicable, and prepare the acetabulum per the implant manufacturer's technique. Torque applied during dislocation can move the pelvis away from the initial alignment.

[0146] In one method of use, the surgical orientation device 172 can provide the user with options as to how to proceed. In one method of use, the surgeon can set the anteversion and / or abduction cup angle by inputting a target angle into the surgical orientation device 172. In one method of use, the surgeon can set the target anteversion and / or abduction cup angle by communicating the target anteversion and / or abduction cup angle from the external output device 130. In one method of use, the surgeon can set the target anteversion and / or abduction cup angle by communicating the target anteversion and / or abduction cup angle based on data collected by the module 100. In one method of use, the surgeon can set the target anteversion and / or abduction cup angle by adjusting the population average angle based on patient-specific factors. The range of motion detected by the module 100 can suggest a patient-specific increase or decrease in anteversion angle from the population average anteversion angle. In one method of use, the surgical orientation device 172 can store a patient-specific target cup angle determined in part by the module 100 .

[0147] In one method of use, the surgical orientation device 172 can provide options for leg length and joint misalignment. In one method of use, the surgical orientation device 172 can provide options for leg length of the patient's two legs. Leg length and / or joint misalignment measurements can be recorded by the surgical orientation device 172 before and after cup placement. In one method of use, the surgical orientation device 172 can measure leg length from a pre-operative state. In one method of use, the surgical orientation device 172 can measure joint misalignment from a pre-operative state. In one method of use, the surgical orientation device 172 can measure changes in registered points.

[0148] The surgeon can remove the orientation sensing device 204 from the second assembly 606. The orientation sensing device 204 and the surgical orientation device 172 can be used to guide the placement of the cup in a predetermined orientation. The surgeon can connect the orientation sensing device 204 to the impactor 300A. In an embodiment, the orientation sensing device 204 can be removably connected to a universal impactor adapter. The universal impactor adapter allows the orientation sensing device 204 to be connected to any impactor.

[0149] In one method of use, the orientation sensing device 204 can be coupled to an impactor 300A as shown in FIG. 11 . The orientation sensing device 204 can determine a cup angle relative to a reference plane when the impactor 300A is moved. The impactor 300A can include a shell 312A. Movement of the shell 312A is cushioned by a plurality of spring members 340, 344 configured to absorb at least some of the impact of engagement in the impactor 300A. The shell 312A can include a coupler that couples the orientation sensing device 204 to the shell 312A. An acetabular cup can be threaded onto the tip component 348. A user can select an appropriate cup adapter for the desired impactor. The orientation sensing device 204 can be coupled to the impactor 300A to derive the cup angle, as described herein.

[0150] The acetabular cup can be inserted into the acetabulum and positioned at a desired angle. As described herein, the surgeon can save the patient-specific target angle with the surgical orientation device 172. The surgical orientation device 172 can guide the surgeon when placing the cup relative to the patient-specific target angle. As described herein, the target abduction and anteversion angles can be cup angles determined by pre-operative planning based on data from module 100. The target abduction and anteversion angles from the pre-operative planning can be inputs to system 600.

[0151] In one method of use, when the orientation sensing device 204 is attached to the impactor 300A or any other impactor via the universal impactor adapter, the surgical orientation device 172 can display the tilt and anteversion angles of a radiograph of the impactor 300A. In one method of use, the surgical orientation device 172 can display the tilt and anteversion angles of a radiograph of the impactor 300A relative to the anterior plane of the pelvis. In one method of use, the surgical orientation device 172 can display the tilt and anteversion angles of a radiograph of the impactor 300A relative to a vertical plane. In one method of use, the surgical orientation device 172 can display the tilt and anteversion angles of a radiograph of the impactor 300A relative to a plane that approximates the anterior pelvic plane. The angles of the impactor 300A can be calculated in real time.

[0152] The surgical orientation device 172 can graphically display when the orientation sensing device 204 is guided to the patient-specific target abduction and anteversion angles. The surgical orientation device 172 can include a mark, such as a target or a hemispherical lens, with the patient-specific abduction and anteversion angles positioned at the center of the target or hemispherical lens. The surgical orientation device 172 can include a mark, such as a dot or crosshairs, to indicate movement of the impactor 300A relative to the target or hemispherical lens. Aligning the mark with the center of the target or hemispherical lens can indicate that the impactor 300A is aligned with the patient-specific target cup angle. In one method of use, the surgeon aligns the crosshairs with the center of the hemispherical lens. In one method of use, the surgeon aligns a bubble level. In one method of use, the surgeon aligns two markings. In one method of use, the surgeon substantially aligns the moving marking with the fixed marking. In one method of use, the surgeon moves indicia in the graphical user interface of the surgical orientation device 172 by moving the impactor 300A. In one method of use, the surgeon moves indicia in the graphical user interface of the surgical orientation device 172 by moving the orientation sensing device 204. Aligning visual indicators displayed on the surgical orientation device 172 can guide the user to position the impactor 300A at the desired patient-specific target cup angle. The indicia can be moved in real time.

[0153] The surgical orientation device 172 can graphically display the patient-specific abduction and anteversion angles. As described herein, the patient-specific abduction and anteversion angles can be inputs for the system 600, determined in part by motion detected by one or more modules 100. In one method of use, the markings align when the impactor 300A is positioned at the patient-specific target abduction angle. In one method of use, the surgical orientation device 172 provides a graphical display to assist the surgeon in aligning the cup with the patient-specific target angle. The surgical orientation device 172 can be coupled to the first assembly 604 during cup placement. The surgical orientation device 172 can be within the surgical field during cup placement. The surgical orientation device 172 can be coupled to the pelvis during cup placement.

[0154] In one method of use, the surgical orientation device 172 displays patient-specific target angles determined by the pre-operative plan. The patient-specific target abduction and anteversion angles may be displayed statically. In one method of use, the surgical orientation device 172 displays suggestions to the surgeon based on the pre-operative plan. The suggestions may include increasing the target anteversion angle from a population mean. The suggestions may include decreasing the target anteversion angle from a population mean. The suggestions may include using the population mean as the patient-specific target anteversion angle. As described herein, the displayed angles may be calculated according to radiographic definitions.

[0155] The surgical orientation device 172 can provide the cup angle relative to any reference plane, including those described herein. The surgical orientation device 172 can provide the cup angle relative to a vertical plane. The surgical orientation device 172 can provide the cup angle relative to a plane that approximates the anterior pelvic plane. The surgical orientation device 172 can provide the cup angle relative to a plane obtained during table registration. The surgical orientation device 172 can provide the cup angle relative to a plane that includes a vector for gravity.

[0156] In some embodiments, the surgeon understands that the cup angle may change during impaction. In some embodiments, the cup angle is displayed by the start of impaction, typically after the first mallet strike. In some methods of use, the surgeon typically strikes the impactor several times during cup placement. In some methods of use, these strikes may change the orientation of the cup. In some embodiments, the surgical orientation device 172 displays only the cup angle from before impaction. In some methods of use, the surgeon repeats the calibration by coupling the orientation sensing device 204 to the system 600 so that the orientation sensing device 204 is in a fixed orientation relative to the surgical orientation device 172. The surgeon then moves the orientation sensing device 204 back toward the impactor 300A to confirm the cup angle. The system 600 can display the current cup angle after impaction. In some embodiments, the surgeon can visually confirm the cup angle before proceeding.

[0157] After positioning the cup, the user can attach the second assembly 606 to the first assembly 604. In one method of use, the user can measure length and / or joint misalignment. In one method of use, the user can measure both legs of the patient to determine leg length. In one embodiment, the surgeon can manually reposition the femur in orientation before cup placement. In one method of use, points can be registered after cup placement. In one method of use, measurements can be taken to compare leg length before and after cup placement. In one method, measurements can be taken to compare joint misalignment before and after cup placement.

[0158] The method may include projecting light from optical element 174 after cup placement. In some methods of use, the incidence of light 180 may not be aligned with the markings after cup placement. In some methods of use, the femur has moved from its pre-operative orientation. In some methods, the surgeon positions the leg so that optical element 174 projects light onto the leg. In some embodiments, the surgeon can manually reposition the femur. The method may include repositioning the femur by aligning the incidence of light with the prior markings or records of the incidence of light 180. In some embodiments, the surgeon can reposition the femur so that it is in the same position before and after cup placement.

[0159] In one method of use, the surgeon can register a point after repositioning the femur. The surgeon can position the distal end 680 of the probe 678 at the point. The orientation of the orientation sensing device 204 and the extension of the probe 678 can be input into the surgical orientation device 172. These data can enable the surgical orientation device 172 to output the amount of change in leg length and leg misalignment. With the tip of the distal end 680 in contact with the desired point, the system 600 processes data from one or more sensors in the orientation sensing device 204 to determine the change from measurements taken before cup placement. The surgical orientation device 172 can display the change in leg length and / or leg misalignment.

[0160] 3. Method for the anterior approach FIG. 7 shows a hip guide system 600 that may be adapted to guide a hip procedure from an anterior approach.

[0161] In one embodiment, the guidance system 600 is configured to locate relevant anatomical features to aid in the placement of the prosthetic hip joint. In one method, preoperative imaging techniques are used. In one method of use, the surgeon can use a standing or supine anteroposterior (AP) radiograph of the pelvis. FIG. 12 shows a standing AP radiograph taken while the patient is standing with the legs in neutral rotation and shoulder-width apart. The radiographic tube-to-film distance should be 120 cm, with the crosshairs centered at the midpoint between the upper edge of the pubic symphysis and a line drawn connecting the anterior superior iliac spines (ASIS). The coccyx should be centered in line with the pubic symphysis, and the iliac crests, obturator foramina, and radiographic teardrops should be symmetrical in appearance. For proper pelvic tilt or abduction, a gap of 1 to 3 cm should be found between the tip of the coccyx and the upper edge of the pubic symphysis. This positioning can be important for measuring the patient-specific Rim Teardrop (RT) angle.

[0162] To obtain a patient-specific rim teardrop (RT) angle from an AP pelvic radiograph, the surgeon can complete one or more of the following steps: The surgeon can draw a line on the radiograph connecting the floors of the teardrops. The surgeon can draw a line from the lateral-most point on the acetabular rim (R) on the operative side through the floor of the teardrop (T) to the horizontal interteardrop line. If osteophytes are present on the rim (R), the surgeon can draw a line through the lateral-most osteophyte. The surgeon can measure the angle between the interteardrop line and the drawn RT line. This patient-specific RT abduction angle can be an input for the system 600.

[0163] Figure 13 shows patient positioning for an anterior hip approach. In an anterior hip approach, the patient should be placed in a supine position. When positioning the patient prior to surgery, the surgeon must be careful to align the patient's spine and femur in a horizontal plane parallel to the long edge of the operating table. The surgeon can ensure the patient is positioned in the proper position, for example, in the supine position.

[0164] System 600 may be partially assembled for calibration as described herein. Orientation sensing device 204 may be fixed in position relative to surgical orientation device 172. Surgical orientation device 172 and orientation sensing device 204 may be calibrated.

[0165] The system 600 can be attached to the pelvis as shown in FIG. 7. In one method, fixation pins 610, 612 are placed parallel to the ipsilateral iliac crest. The fixation pins 610, 612 are placed in a manner similar to pin placement for pelvic external fixation. The fixation pins 610, 612 enter the iliac crest at its superior surface and extend between the medial and lateral bony tables of the iliac crest. To eliminate the obstacle of subsequent femoral exposure and broaching via an anterior approach, in one method of use, an anterior fixation pin should be placed 2-4 cm posterior to the ASIS. In one technique, one fixation pin 610, 612 is positioned at the iliac crest 2-4 cm posterior to the ASIS.

[0166] The surgeon can register the fastened configuration or home position. In one technique, the distal end 680 of the probe 678 can be engaged with a point on the fixed base 602. The probe 678 can be vertical in the home position. The orientation sensing device 204 can be vertical in the home position.

[0167] The surgeon can position the distal end 680 of the probe 678 at various anatomical landmarks or points. Landmarks include the two anterior superior iliac spines (ASIS), which are bony processes of the ilium. The anterior superior iliac spines may be visualized and / or agitated by the surgeon during surgery. The anterior superior iliac spines are the anterior ends of the iliac crests of the pelvis. An inter-ASIS line extends between these landmarks. An inter-ASIS line extends between the ipsilateral and contralateral ASIS. In other methods of use, other landmarks are used. Other landmarks that may be used include the anterior insertion points of the transacetabular ligament onto the ilium, ischium, pubis, ischium, midpoint of the inferior surface of the acetabular notch, the anterior superior iliac spine, the anterior inferior iliac spine, the convergence of the acetabulum and anterior inferior iliac spine, and other landmarks known in the art.

[0168] The system 600 has one or more processing devices that receive data and determine the relative position and / or orientation of anatomical landmarks when the probe 678 contacts these landmarks. The data may be generated by inertial sensors, as discussed elsewhere herein, or by other types of sensors in the system 600. Preferably, the sensors are small enough to be mounted on or in a handheld housing or embedded in an instrument, such as the surgical orientation device 172 and the orientation sensing device 204. The system 600 also preferably has a memory device for at least temporarily storing a portion of these points. The system 600 also preferably has the capability to at least temporarily store associated position and / or orientation data when the probe 678 contacts an anatomical landmark. In one method of use, the system 600 records the position and / or orientation of the probe 678 when it contacts each anatomical landmark or point.

[0169] In one method of use, a user can measure leg length and joint misalignment. At the surgeon's discretion, the system 600 can be used to guide the condition, location, and / or orientation of the femur prior to hip replacement. In one embodiment, a marking Fm can be made on the proximal femur. In one embodiment, a structure such as a pin is attached to the femur. In one embodiment, a burr or prong is made in the femur. The distal end 680 of the probe 678 can be brought into contact with the femoral marking Fm. The surgical orientation device 172 can be signaled to record the orientation of the orientation sensing device 204. In one method of use, the system 600 includes an optical element 174. A laser light can be used to project a point, plane, and / or crosshairs onto a target, including, but not limited to, an anatomical feature or landmark. The surgeon can mark one or more points along the line of incidence 180 of the light on the optical element 174.

[0170] a. Anterior pelvic plane The system can calculate the anterior pelvic plane. The anterior pelvic plane can be defined as the plane created by the two anterior superior iliac spines (ASIS) and the anterior surface of the pubic symphysis. Three points provide adequate information for calculating the plane. These anatomical features are visible / palpable while the patient is in a supine position. In one method, the probe 678 registers the anterior pelvic plane with direct contact of anatomical landmarks when the patient is in a supine position. The system 600 can then provide guidance data for the orientation of the hip joint instrument (e.g., impactor 300A, or any impactor with a universal impactor adapter) relative to the anterior pelvic plane. In one embodiment, the system 600 can provide user guidance data in real time. In an anterior approach, the patient is positioned on their back, and the anterior pelvic plane is oriented substantially horizontally, e.g., substantially parallel to the plane of the table on which the patient is positioned.

[0171] The system 600 can determine the anterior pelvic plane by registering points 1, 2, and 3 as shown in FIG. 14 . The surgeon can register points 1, 2, and 3. The illustrated embodiment shows point 1 at the left hip, point 2 at the right hip, and point 3 at the patient's right hip. In one approach, point 1 is the ipsilateral ASIS. In one approach, the distal end 680 of the probe 678 is placed at the ipsilateral ASIS landmark. The probe 678 can be stationary, and the position and / or orientation of the orientation sensing device 204 can be recorded by the surgical orientation device 172. The surgeon can enter an input (e.g., by depressing a button on the surgical orientation device 172) to register point 1. The surgical orientation device 172 can indicate that point 1 has been recorded. Additionally, the distance the probe 678 is extended to contact the ipsilateral ASIS, as captured by the camera of the orientation sensing device 204, can be recorded by the orientation device 172.

[0172] In some methods, point 2 is the contralateral ASIS. In some methods, the distal end 680 of the probe 678 is placed at the contralateral ASIS landmark. The probe 678 can be stationary, and the position and / or orientation of the orientation sensing device 204 can be recorded by the surgical orientation device 172. The surgeon can enter an input (e.g., to depress a button on the surgical orientation device 172) to register point 2. The surgical orientation device 172 can indicate that point 2 has been recorded. Also, the distance that the probe 678 is extended to contact the contralateral ASIS, as captured by the camera of the orientation sensing device 204, can be recorded by the orientation device 172.

[0173] In some methods, point 3 is the anterior surface of the pubic symphysis. In some methods, the distal end 680 of the probe 678 is placed at a pubic landmark. In some methods, either pubic eminence can be used as point 3. In some embodiments, the contralateral pubic eminence is used as point 3. The probe 678 can be stationary, and the position and / or orientation of the orientation sensing device 204 can be recorded by the surgical orientation device 172. The surgeon can enter an input (e.g., by depressing a button on the surgical orientation device 172) to register point 3. The surgical orientation device 172 can indicate that point 3 has been recorded. Also, the distance the probe 678 is extended to contact the pubic symphysis, as captured by the camera of the orientation sensing device 204, can be recorded by the orientation device 172. The process for recording points can be repeated for one or more additional points.

[0174] The distance related to the extension of the probe 678 can be used along with position and / or orientation data from the orientation sensing device 204. In one method, the surgical orientation device 172 and / or the orientation sensing device 204 convert the images of the camera 184 into an extension measurement of the probe 678. When registering anatomical points, the camera can capture images of the markings on the probe 678. The system 600 can provide an accurate determination of the translational position of the probe 678. The system 600 uses the length measurements and data from the orientation sensing device 204 to determine the location of the distal end 680 of the probe 678 at points 1, 2, and 3.

[0175] Once the aforementioned points of the pelvis have been guided and the data recorded into the surgical orientation device 172, the anterior pelvic plane can be calculated from the data of the guided points. The system 600 can calculate the anterior pelvic plane from the three points recorded by the system 600. The three points are shown in FIG. 14. A line between the ASISs connects points 1 and 2. The line between the ASISs provides a straight line between the ipsilateral and contralateral ASISs. The anterior pelvic plane can be considered a horizontal plane that pivots around an axis between the ASISs depending on the location of point 3. FIG. 14 shows the anterior pelvic plane (APP) determined by point 3. The anterior pelvic plane includes the ipsilateral ASIS, the contralateral ASIS, and the anterior surface of the pubic symphysis.

[0176] In one method of use, the orientation of the anterior pelvic plane can be a reference for placement of the cup portion of a hip prosthesis. The surgical orientation device 172 can display information about the anterior pelvic plane. In one method of use, the abduction and anteversion angles for cup placement in a total hip replacement can be relative to the anterior pelvic plane. In one embodiment, the anterior pelvic plane is determined by the surgical orientation device 172 and / or the orientation sensing device 204.

[0177] b. Adjusted pelvic plane In some methods of use, a reference plane is adjusted. In some methods of use, a table plane is estimated to adjust the reference plane. Any method or method step for establishing a table plane described herein may be utilized. The table plane may be a horizontal plane or a generally horizontal plane. The patient may be positioned so that the coronal plane of the pelvis is flat, e.g., parallel and / or horizontal to the table. The user may visually confirm that the coronal plane is flat, or may use a device to position the patient's body to align the coronal plane with the plane of the table top. In some embodiments, a reference plane based on the plane of the table top may be input into the system 600. Table registration provides clinical value. In some techniques, the table plane may be input for a secondary reference plane to the anterior pelvic plane.

[0178] During table registration, the probe 678 is coupled to the orientation sensing device 204. In one method of use, the probe 678 and the orientation sensing device 204 are constrained from movement together during table registration. In an embodiment, the probe 678 can be decoupled from other components of the first assembly 604 and / or the second assembly 606. In one method of use, the system 600 is assembled such that the first assembly 604 and the second assembly 606 are coupled to the patient via the fixation pins 610, 612. In an embodiment, the probe 678 can be coupled to the first assembly 604, the second assembly 606, and / or the pelvis during table registration.

[0179] The probe 678 may be aligned with the long axis of the body. The probe 678 may be held substantially parallel to the plane of the table. The surgeon may visually inspect the probe 678 from one or more locations. For example, the user may inspect the probe 678 from a superior perspective and a lateral perspective.

[0180] The probe 678 can be held constant and the position and / or orientation of the orientation sensing device 204 can be recorded by the surgical orientation device 172. The user can enter an input to register the table (e.g., to depress a button on the surgical orientation device 172). The user can interact with a user interface on the surgical orientation device 172 to signal the surgical orientation device 172 to capture the position and / or orientation of the orientation sensing device 204. The surgical orientation device 172 can indicate that the table plane has been recorded.

[0181] As described herein, the orientation sensing device 204 and surgical orientation device 172 may include one or more inertial sensors. The one or more inertial sensors can detect gravity and provide a downward vector. The table plane provides an estimate of the coronal orientation.

[0182] In some embodiments, the method may include calculating an adjusted plane (adjusted). The inter-ASIS line connects point 1 and point 2, as discussed herein. The inter-ASIS line provides a straight line between the ipsilateral and contralateral ASIS. Points 1 and 2 may be recorded by system 600 as described herein. Points 1 and 2 may be recorded as part of the method to calculate the anterior pelvic plane. Points 1 and 2 may be recorded independently of the method to calculate the anterior pelvic plane. In some methods, point 1 is the ipsilateral ASIS. In some methods, point 2 is the contralateral ASIS. These anatomical features are visible / palpable while the patient is in the supine position. The adjusted plane may be calculated in addition to or as an alternative to the anterior pelvic plane. System 600 may provide user-guided data for the orientation of the hip joint instrument (e.g., impactor 300A or any impactor with a universal impactor adapter) relative to the adjusted plane.

[0183] The adjusted plane is determined by rotating the anterior pelvic plane about a line between the ASIS so that it is perpendicular to the force of gravity. The adjusted plane utilizes a measurement of gravity. As described herein, the surgical orientation device 172 includes one or more inertial sensors. As described herein, the orientation sensing device 204 includes one or more inertial sensors. In certain embodiments, inertial data from the one or more inertial sensors is used to calculate the adjusted plane. The surgical orientation device 172 and / or the orientation sensing device 204 may include an accelerometer that can provide a measurement of the direction of gravity. The one or more inertial sensors can provide a vector aligned with vertical, e.g., a downward direction. The accelerometer can transform the vertical vector (e.g., by rotating it 90 degrees) to generate a horizontal vector. The accelerometer can provide orientation data and / or position data so that the adjusted plane is perpendicular to gravity.

[0184] The surgical orientation device 172 and / or the orientation sensing device 204 can provide a reference to zero gravity. Zero gravity, as referred to herein, generally refers to an orientation in which the axis of the sensor is perpendicular to the force of gravity, thereby experiencing no angular misalignment, e.g., tilt, pitch, roll, or yaw, relative to the gravity vector.

[0185] In some methods of use, the orientation sensing device 204 may be positioned in a manner other than horizontal to measure the direction of gravity. In some methods of use, the orientation sensing device 204 may measure gravity when in a fixed position. In some methods of use, the orientation sensing device 204 may be positioned vertically or substantially vertically to measure gravity. In some methods of use, the orientation sensing device 204 may measure gravity when in contact with a point or anatomical landmark. In some methods of use, the orientation sensing device 204 may measure gravity when in contact with Point 1. In some methods of use, the orientation sensing device 204 may measure gravity when in contact with Point 2.

[0186] FIG. 15 illustrates the adjusted plane. The adjusted plane can be considered a horizontal plane that pivots around a line between the ASISs based on gravity measurements. Once the aforementioned points on the pelvis are guided and data is recorded into the surgical orientation device 172, the adjusted plane can be calculated from the data about the guided points and gravity measurements. The adjusted plane includes the ipsilateral ASIS and the contralateral ASIS. The adjusted plane includes the line between the ASISs. The system 600 can combine a horizontal vector with points 1 and 2 to calculate the adjusted plane. In one embodiment, the adjusted plane can be considered a horizontal plane determined by the direction of gravity. In one embodiment, the adjusted plane can be considered a horizontal plane that includes the line between the ASISs.

[0187] As described herein, three anatomical landmarks are registered for the anterior pelvic plane. The ipsilateral ASIS, contralateral ASIS, and pubic symphysis as registered by probe 678 define the anterior pelvic plane. As described herein, two anatomical landmarks are registered for the adjusted plane. The two landmarks define a line between the ASIS.

[0188] In one embodiment, the surgical orientation device 172 can provide a modified reference frame by, for example, rotating the anterior pelvic plane about a line between the ASIS based on the direction of gravity. In one embodiment, the surgical orientation device 172 can rotate the anterior pelvic plane about a line between the ASIS to provide a modified reference frame that is aligned with the horizontal. A measurement of gravity can cause the surgical orientation device 172 to rotate the anterior pelvic plane. The orientation sensing device 204 and / or one or more inertial sensors of the surgical orientation device 172 can provide data to determine how to translate, e.g., rotate, the plane containing the axis between the ASIS so that it is perpendicular to the force of gravity.

[0189] The adjusted plane provides a check against gross errors from anatomical registration. The adjusted plane provides a reference plane that is not affected by pelvic tilt. The adjusted plane provides a reference plane that is not significantly affected by errors in registration due to soft tissue. The adjusted plane is calculated, in part, when the probe 678 is properly aligned with a table or other horizontal plane. The adjusted plane provides a horizontal plane that may be useful for comparing the induced cup angle with pre- and / or post-operative images. Pre- and / or post-operative images, such as x-rays, are captured within a horizontal reference plane. The adjusted plane can provide a horizontal reference plane that approximates the horizontal reference plane of the imaging technique.

[0190] The orientation of the adjusted plane can be a reference for placement of the cup portion of a hip prosthesis. The surgical orientation device 172 can display information about the adjusted plane. In one method of use, patient-specific abduction and anteversion angles for cup placement in a total hip replacement can be relative to the adjusted plane.

[0191] c. Cup placement Once registration is complete, the user can proceed to dislocate the hip joint, resect the femoral head, and prepare the acetabulum. The surgeon can prepare the impactor 300A and the acetabular cup. The surgeon can couple the orientation sensing device 204 to the impactor 300A.

[0192] The surgeon can select a patient-specific target cup angle based on the pre-operative plan. The acetabular cup can be inserted into the acetabulum and positioned at the desired angle. The surgical orientation device 172 can guide the surgeon in navigating to the patient-specific target cup angle. The surgical orientation device 172 can graphically display as the orientation sensing device 204 is navigated to the patient-specific abduction and anteversion angles. The patient-specific abduction and anteversion angles can be the pre-operative cup angles determined by module 100. The surgical orientation device 172 can graphically display the abduction and anteversion angles as the orientation sensing device 204 and impactor 300A are moved.

[0193] The surgical orientation device can provide the cup angle relative to any reference plane, including the reference planes described herein, including the anterior pelvic plane and adjusted planes. The acetabular shell can be inserted into the acetabulum and positioned at a patient-specific target angle. The surgical orientation device 172 can guide the surgeon in navigating to the appropriate cup angle. The surgical orientation device 172 can graphically display as the orientation sensing device 204 is navigated to the patient-specific target abduction and anteversion angles. The desired abduction and anteversion angles can be pre-operative cup angles based in part on the module 100. The surgical orientation device 172 can graphically display the patient-specific target abduction and anteversion angles as the orientation sensing device 204 is moved. The surgeon can align the impactor 300A at the desired cup angle. Aligning the visual indicators on the surgical orientation device 172 can guide the user to position the impactor 300A at the desired cup angle. Patient-specific abduction and anteversion angles may be displayed statically or dynamically. Cup angles may be confirmed after fitting by repeating one or more of the methods described herein.

[0194] The surgical orientation device 172 may include indicia, such as a target or a hemispherical lens, to indicate the patient-specific target abduction and anteversion angles. The surgical orientation device 172 may include indicia, such as a dot or crosshairs, to indicate movement of the impactor 300A. Aligning the indicia with the center of the target or hemispherical lens can indicate that the impactor 300A is aligned with the patient-specific target cup angle. The indicia can move in real time. The method for cup placement and verification may include any of the steps described herein.

[0195] If a femoral landmark Fm is acquired during a procedure prior to separating the natural joint, the same landmark can be acquired after the cup is placed to verify that cup placement has not changed leg length, leg offset from the patient's torso, or both. The distal end 680 of the probe 678 can be brought into contact with the same landmark (e.g., Fm) acquired earlier in the procedure. The orientation of the orientation sensing device 204 and the extension of the probe 678 can be input into the surgical orientation device 172. This data enables the surgical orientation device 172 to output the amount of change in leg length and / or leg offset.

[0196] The optical element 174 can provide a visual guide to recreate the original position of the femur relative to the pelvis after cup placement. When measuring changes in leg length and lateral joint displacement, the apparent change is sensitive to changes in the orientation of the femur relative to the pelvis. The user can reposition the femur before measuring changes in leg length and joint displacement so that the orientation of the femur relative to the pelvis is the same as when the pre-operative baseline measurements were taken.

[0197] 4. Comparison of the adjusted plane with the anterior pelvic plane FIG. 16 shows a comparison between the anterior pelvic plane and the adjusted plane. As described herein, both the anterior pelvic plane and the adjusted plane include the ASIS line. The anterior pelvic plane includes point 3 to define the plane. The adjusted plane uses the direction of gravity to define the plane. In one embodiment, the anterior pelvic plane and the adjusted plane are coaxial about the ASIS line. The adjusted plane is a rotation of the anterior pelvic plane about the ASIS line. The adjusted plane and the anterior pelvic plane can form an angle alpha. Angle alpha can be a measurement of pelvic tilt. Angle alpha can measure the difference between the anterior pelvic plane and horizontal. Angle alpha can adjust the anterior pelvic plane so that the cup angle more closely matches that shown on the post-operative x-ray. In one embodiment, the adjusted plane adjusts tilt. In one embodiment, the adjusted plane adjusts the tilt of the pubic bone relative to the ASIS line.

[0198] The adjusted plane has clinical value. Pre-operative and post-operative radiographs produce two-dimensional images in a horizontal plane. The image receptor is positioned horizontally with the patient in a supine position. The image receptor captures residual light as it exits the patient's body. The patient's anatomy is projected onto the horizontal plane of the image receptor. For pelvic radiographs, the predetermined projection is the anterior-posterior projection. The guided angle can be correlated to the display of the post-operative radiograph through the adjusted plane. The adjusted plane can provide a horizontal reference plane that approximates the horizontal reference plane of the imaging technique. There is a clinical benefit to providing the user during the procedure with a guided cup angle that reflects that measured on the post-operative radiograph. The guided cup angle based on the adjusted plane can be provided in addition to, or as a substitute for, the guided cup angle based on the anterior pelvic plane. The adjusted plane-based derived cup angle may be provided in addition to, or as a substitute for, the table plane-based derived cup angle.

[0199] Adjustment from the anterior pelvic plane to the adjusted plane can provide the user with a cup angle that correlates to a clinically expected cup angle. Adjustment from the anterior pelvic plane to the adjusted plane can provide the user with a cup angle that correlates to what the user wants to see during surgery (e.g., a comparison between an image of the cup and the output of the system 600). Adjustment from the anterior pelvic plane to the adjusted plane can provide the user with a cup angle that correlates to what the user wants to see in a post-operative image (e.g., a comparison between the output of the system 600 and a post-operative image). A user, such as a surgeon, correlates the output of the system 600 with a number that correlates to clinical experience, for example, calibrated to what the user wants to see in a post-operative image. The post-operative image can be a supine film taken six weeks after surgery. The post-operative image is taken from a horizontal cross-section of the patient's body. The adjusted plane can be more similar to the plane of the post-operative image.

[0200] With system 600, the surgeon is provided with an output to assist them in guiding them to proper cup placement. The output can be an abduction angle and an anteversion angle that are output to surgical orientation device 172. The user can navigate to the desired abduction and anteversion angle by moving components of system 600, such as impactor 300A. When the surgeon places the cup at the desired abduction and anteversion angle, the user wants to see the same or similar angles in the post-operative images. The user's confidence in navigating system 600 is increased when the abduction and anteversion angles generated by system 600 match the post-operative angles.

[0201] The systems and methods described herein can improve the placement of a prosthetic hip joint using guidance in combination with preoperative imaging and landmark referencing. These hip joint procedures generally guide the prosthetic hip joint into an orientation within the acetabulum, which minimizes the chance of dislocation due to impingement of the femoral neck on the cup or bone around the acetabulum, or other reasons related to suboptimal orientation of the prosthesis. Various techniques utilize population averages of proper placement, while others are amenable to patient-specific refinement.

[0202] C. Post-operative planning system for anterior and posterior approaches 1. Post-operative planning system Discussed below are various pelvic mobility modules, systems, and methods for total hip arthroplasty (THA) that can be used to improve patient outcomes by increasing the likelihood of proper placement of the medical prosthesis. These systems and methods may focus on understanding the patient's anatomy. These systems and methods may additionally or alternatively measure, quantify, and / or track pelvic mobility post-operatively to track recovery or fit.

[0203] Inertial measurements may be taken post-surgery for a variety of reasons, including to monitor recovery and improve compliance with physical therapy. To measure pelvic mobility, a user moves through a range of motion and data is captured and processed. A patient may take module 100 home after surgery. Module 100 may enable post-surgery functionality. In some embodiments, module 100 may track physical therapy. In some embodiments, module 100 may track patient compliance. In some embodiments, module 100 may be an informational or educational tool. Data from module 100 may be transmitted to external output device 130. Data from module 100 may be transmitted to external storage device 128. The data may be processed and analyzed as described herein.

[0204] While these inventions have been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present application extends beyond the specific disclosed embodiments to other alternative embodiments and / or uses of the invention, as well as obvious modifications and equivalents thereof. Also, while numerous variations of the invention have been shown and described in detail, other modifications within the scope of the invention will be readily apparent to those skilled in the art based on this disclosure. It is also contemplated that various combinations and subcombinations of specific features and aspects of the embodiments may be made and still fall within the scope of the present application. For example, the present application contemplates that the connection hub alone, or the connection hub in combination with any of the other modules, may comprise another aspect. Alternatively, any one or any combination of the modules may be directly connected to the umbrella hub or overhead support to form another aspect. Accordingly, various features and aspects of the disclosed embodiments can be combined with or substituted for one another to form various aspects of the disclosed embodiments. It is therefore intended that the scope of the invention disclosed herein should not be limited by the specifically disclosed embodiments set forth above, but should be determined solely by a fair interpretation of the claims that follow.

[0205] Likewise, this method of disclosure is not to be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. Accordingly, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment.

[0206] Furthermore, the present invention preferably includes the following examples. [Section 1] 1. A system comprising: a module comprising one or more inertial sensors configured to be positioned relative to a patient's anatomy, the module configured to measure mobility for surgical planning. [Section 2] Item 10. The system of item 1, wherein the module includes a biocompatible adhesive configured to adhere an object to the patient's skin. [Section 3] Item 1, wherein the module is embedded in clothing. [Section 4] Item 10. The system of Item 1, wherein the one or more inertial sensors comprise an accelerometer. [Section 5] Item 1, wherein the one or more inertial sensors comprise a gyroscope. [Section 6] Item 10. The system of Item 1, wherein the module is configured to transmit data from the module to an external output device. [Section 7] Item 7. The system of item 6, wherein the external output device is a smartphone. [Section 8] Item 8. The system according to item 7, further comprising the smartphone. [Section 9] Item 8. The system of item 7, wherein the smartphone is configured to receive patient-specific data obtained from the module. [Section 10] Item 7. The system of item 6, wherein the external output device is a surgical orientation device configured for use during a surgical procedure. [Section 11] Item 11. The system of item 10, further comprising the surgical orientation device. [Section 12] Item 11. The system of clause 10, wherein the surgical orientation device is configured to receive patient-specific data obtained from the module. [Section 13] 1. A system comprising a surgical orientation device with an inertial sensor, The system includes a surgical orientation device configured to facilitate guiding an acetabular cup to a desired target angle, the surgical orientation device detects the orientation and rotation of the surgical orientation device relative to a reference frame, and the surgical orientation device is configured to receive one or more mobility measurements for surgical planning. [Section 14] Item 14. The system of item 13, further comprising an orientation sensing device. [Section 15] Item 14. The system of item 13, wherein the surgical orientation device includes a transceiver for transmitting data or receiving data from one or more sensors of an orientation sensing device. [Section 16] Item 14. The system of item 13, wherein the surgical orientation device comprises a transceiver for transmitting data or receiving data from a module, the module being configured to measure mobility. [Section 17] 14. The system of claim 13, wherein the surgical orientation device includes a transceiver for transmitting data or receiving data from an external output device. [Section 18] Item 18. The system of item 17, wherein the external output device is a smartphone. [Section 19] Item 19. The system of item 18, wherein the smartphone is configured to receive patient-specific data obtained from the module. [Section 20] 1. A method for determining patient mobility, comprising: positioning a module with one or more inertial sensors relative to the patient's anatomy; measuring mobility with said module; The method comprising: [Section 21] Item 21. The method of item 20, wherein the mobility is pelvic mobility. [Section 22] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's sacrum. [Section 23] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's femur. [Section 24] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's spine. [Section 25] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module at the patient's ASIS point. [Section 26] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module at a bony prominence site identified by palpation of the patient's skin. [Section 27] 21. The method of claim 20, wherein positioning the module includes positioning the module on the patient's skin over the patient's underlying anatomy. [Section 28] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module at the patient's pubic bone. [Section 29] 21. The method of claim 20, wherein positioning the module includes positioning the module at a tactile location on the patient's body. [Section 30] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's lower back. [Section 31] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's upper back. [Section 32] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's neck. [Section 33] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on a patient's pelvis. [Section 34] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's tibia. [Section 35] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on a vertebra of the patient. [Section 36] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's sternum. [Section 37] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's ribs. [Section 38] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's skull. [Section 39] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on a facial bone of the patient. [Section 40] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's humerus. [Section 41] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's scapula. [Section 42] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's clavicle. [Section 43] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's ulna. [Section 44] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's radius. [Section 45] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on a carpal bone of the patient. [Section 46] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's fibula. [Section 47] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on the patient's tarsus. [Section 48] 21. The method of claim 20, wherein the step of positioning the module includes the step of positioning the module on a metatarsal bone of the patient. [Section 49] 21. The method of claim 20, wherein positioning the module includes positioning the module on the patient for one hour or more. [Section 50] 21. The method of claim 20, wherein positioning the module includes positioning the module on the patient for one or more days. [Section 51] 21. The method of claim 20, wherein positioning the module includes positioning the module on the patient for one week or more. [Section 52] 21. The method of clause 20, wherein the one or more inertial sensors comprise an accelerometer. [Section 53] 21. The method of clause 20, wherein the one or more inertial sensors comprise a gyroscope. [Section 54] 21. The method of clause 20, further comprising transmitting data from the module to an external output device. [Section 55] 55. The method of claim 54, wherein the external output device is a smartphone. [Section 56] 1. A method for positioning a medical prosthesis, comprising: examining pre-operative measurements of pelvic mobility, said measurements being collected with a module comprising one or more inertial sensors; determining a patient-specific target angle taking into account the pre-operative pelvic mobility; aligning the cup to the patient-specific target angle; The step of fitting the cup The method comprising: [Section 57] 57. The method of clause 56, wherein the one or more inertial sensors comprise an accelerometer. [Section 58] 57. The method of clause 56, wherein the one or more inertial sensors comprise a gyroscope. [Section 59] 57. The method of clause 56, further comprising transmitting data from the module to an external output device. [Section 60] 60. The method of claim 59, wherein the external output device is a smartphone. [Section 61] 57. The method of clause 56, further comprising determining the change in leg length before and after cup placement. [Section 62] 57. The method of clause 56, further comprising determining the change in leg length between the two legs. [Section 63] 57. The method of clause 56, further comprising determining a change in joint misalignment before and after cup placement. [Section 64] 57. The method of claim 56, further comprising the steps of projecting a pattern of light onto the patient's leg and recording the incidence of the light before the step of fitting the cup. [Section 65] 65. The method of claim 64, further comprising, after the step of fitting the cup, projecting a pattern of light onto the patient's leg and repositioning the leg to align the recording of the light incidence with the pattern of light. [Section 66] 66. The method of claim 65, further comprising recording points before and after the step of fitting the cup. [Section 67] 57. The method of claim 56, further comprising establishing a vertical plane. [Section 68] 68. The method of clause 67, further comprising the step of establishing a horizontal plane, the vertical plane and the horizontal plane defining a reference frame. [Section 69] 68. The method of claim 67, wherein the patient-specific target angle is measured relative to the vertical plane. [Section 70] 57. The method of clause 56, further comprising establishing a reference plane. [Section 71] positioning a pointer to contact the first point; recording the position and / or orientation of the indicator when the indicator is in contact with the first point; positioning the indicator to contact a second point; recording the position and / or orientation of the indicator when the indicator is in contact with the second point; 57. The method of claim 56, further comprising establishing a reference plane comprising: [Section 72] 72. The method of claim 71, wherein the step of establishing a reference plane further comprises the steps of positioning the indicator so that it contacts a third point, and recording the position and / or orientation of the indicator when it is in contact with the third point. [Section 73] Item 72. The method of item 71, wherein the first point, the second point, and the third point define an anterior pelvic plane. [Section 74] 72. The method of claim 71, wherein the step of establishing a reference plane further comprises the step of positioning the indicator horizontally. [Section 75] Item 72. The method of item 71, wherein the first point and the second point define a line that intersects with the contralateral ASIS. [Section 76] positioning a module with one or more inertial sensors relative to the patient's anatomy; measuring patient-specific pelvic mobility with a module comprising one or more inertial sensors; 1. A method comprising: The method wherein the patient-specific pelvic mobility is considered to determine at least a portion of the surgical plan. [Section 77] 77. The method of claim 76, wherein the patient-specific pelvic mobility is considered to determine the target angle. [Section 78] 77. The method of claim 76, wherein the patient-specific pelvic mobility is considered to determine the type of implant. [Section 79] 77. The method of claim 76, wherein the patient-specific pelvic mobility is considered to determine the type of device. [Section 80] 77. The method of claim 76, wherein the patient-specific pelvic mobility is examined to determine leg length. [Section 81] 77. The method of claim 76, wherein the patient-specific pelvic mobility is examined to determine joint misalignment. [Section 82] 77. The method of clause 76, wherein the one or more inertial sensors comprise an accelerometer. [Section 83] 77. The method of clause 76, wherein the one or more inertial sensors comprise a gyroscope. [Section 84] 77. The method of clause 76, further comprising transmitting data from the module to an external output device. [Section 85] Item 85. The method of item 84, wherein the external output device is a smartphone. [Section 86] a first inertial guidance device comprising one or more inertial sensors; An indicator; a second inertial guidance device comprising one or more inertial sensors; A hip joint guidance system comprising: A hip joint guidance system, wherein the first inertial guidance device, the second inertial guidance device, or the first inertial guidance device and the second inertial guidance device are configured to align the cup to a patient-specific target angle, the patient-specific target angle being determined based on pre-operative pelvic mobility. [Section 87] Item 87. The hip joint guidance system of item 86, further comprising a module comprising one or more inertial sensors and configured to measure the pre-operative mobility of the pelvis. [Section 88] Item 88. The hip joint guidance system of item 87, wherein the first inertial guidance device comprises a transceiver for transmitting data or receiving data from a module. [Section 89] Item 87. The hip joint guidance system of item 86, wherein the second inertial guidance device is configured to couple to an impactor. [Section 90] Item 87. The hip joint guidance system of item 86, further comprising a universal impactor adapter having a coupler, wherein the second inertial guidance device is configured to couple to the impactor with the adapter. [Section 91] Item 87. The hip joint guidance system of item 86, further comprising an optical element. [Section 92] a module configured to generate an output that directs at least a portion of a surgical plan based on the pre-operatively measured joint mobility; a user interface configured to display information related to the output during surgery; and An orthopedic surgery guidance system comprising: [Section 93] Item 93. The orthopedic surgical guidance system of claim 92, further comprising a module comprising one or more inertial sensors and configured to measure pre-operative joint mobility. [Section 94] Item 93. An orthopedic surgical guidance system as described in Item 92, wherein the modules are equipped with transceivers for transmitting and receiving data between the modules. [Section 95] Item 93. An orthopedic surgical guidance system as described in Item 92, wherein the indication indicates the type of implant to be used in the orthopedic surgical procedure. [Section 96] Item 96. The orthopaedic surgical guidance system of Item 95, wherein the indication indicates the use of a dual-mobility hip implant. [Section 97] The orthopedic surgical guidance system of claim 92, wherein the display indicates one or more target angles toward which the surgical instrument is to be aligned and / or one or more target positions toward which the surgical instrument is to be advanced. [Section 98] Item 98. An orthopedic surgical guidance system as described in Item 97, wherein the display indicates the proximity of a surgical instrument to the one or more target angles and / or the one or more target positions. [Section 99] Item 98. The orthopedic surgical guidance system of item 97, further comprising a reamer, the system comprising a module configured to provide an output indicating the position and / or orientation of the reamer relative to the one or more target angles and / or the one or more target positions, and the user interface configured to display the output indicating the position and / or orientation. [Section 100] Item 98. The orthopedic surgical guidance system of item 97, further comprising an impactor, the system comprising a module configured to provide an output indicating the position and / or orientation of the impactor relative to the one or more target angles and / or the one or more target positions, and the user interface configured to display the output indicating the position and / or orientation. [Section 101] Item 93. The orthopaedic surgical guidance system of paragraph 92, further comprising obtaining a reference frame. [Section 102] Item 93. An orthopedic surgical guidance system as described in Item 92, further comprising obtaining a reference frame using an indicator to establish the position and / or orientation of the point. [Section 103] Item 93. An orthopedic surgical guidance system as described in Item 92, further comprising obtaining a reference frame using an indicator to establish the orientation of the axis. [Section 104] Item 93. An orthopedic surgical guidance system as described in Item 92, further comprising obtaining a reference frame using an indicator to establish the position and / or orientation of the axis of gravity. [Section 105] Item 93. An orthopedic surgical guidance system as described in Item 92, further comprising obtaining a reference frame using an indicator to establish the position and / or orientation of the plane. [Section 106] Item 93. An orthopedic surgical guidance system as described in Item 92, further comprising obtaining a reference frame using an indicator to establish the position and / or orientation of a plane that approximates an anatomical plane of the patient. [Section 107] Item 93. The orthopedic surgical guidance system of claim 92, further comprising obtaining a reference frame using an indicator to establish the position and / or orientation of a plane that approximates the plane of the patient image. [Section 108] positioning a module with one or more inertial sensors relative to the patient's anatomy; measuring patient-specific pelvic mobility with a module comprising one or more inertial sensors; 1. A method comprising: The patient-specific pelvic mobility is collected post-operatively. [Section 109] 109. The method of claim 108, further comprising pre-operatively positioning a module equipped with one or more inertial sensors relative to the patient's anatomy, and pre-operatively measuring patient-specific pelvic mobility with the module equipped with one or more inertial sensors. [Section 110] 110. The method of claim 109, further comprising the step of comparing pre-operative and post-operative measurements. [Section 111] 110. The method of claim 109, wherein pre-operative patient-specific pelvic mobility is considered to determine at least a portion of the surgical plan. [Section 112] 109. The method of claim 108, wherein post-operative patient-specific pelvic mobility is considered to determine at least a portion of the physical therapy plan. [Explanation of symbols]

[0207] 1, 2, 3 points 10 Systems 100 modules 102 Outer housing 104 Front 106 Rear 108 Side 110 Indicator, lighting, LED, display section 112 User Input Devices 114 Grasping Features 120 Electronic control unit, electric control unit 122 sensors 124 Power supply section 126 Internal storage 128 External storage device 130 External Output Devices 172 Surgical Orientation Device 180 Incidence of Light 204 Orientation sensing device 300A impactor 312A Shell 348 Advanced Components 600 Hip Joint Guidance System 602 Fixed base 604 First Assembly 606 Second Assembly 610, 612 Fixing pin 662 Dock 678 Probe 680 Distal end APP Anterior Pelvic Plane α angle between the adjusted plane and the anterior pelvic plane

Claims

[Claim 1] 1. A system comprising: a module comprising one or more inertial sensors configured to be positioned relative to a patient's anatomy, the module configured to measure mobility for surgical planning.

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