System for robot-assisted surgery using custom bone registration guide plate and method of manufacture

Abstract

Systems, methods, and devices are described for a robot-assisted orthopedic surgical system mounted on a bone. The system can realize precise positioning of implants, soft tissue balance and tool navigation during surgery, especially during partial or total knee arthroplasty. The system employs a robotic arm with an end effector mounted to a bone to achieve precise positioning of surgical tools, implant location and soft tissue balance. The configurable robot system only needs a small amount of training of surgeons, is visual in operation, is similar to a traditional instrument operation, and is small in occupied area. The system can be used in cooperation with an existing traditional instrument, an instrument special for a patient, a sensor auxiliary system and a computer auxiliary system, the operation time does not need to be increased, and a safer and more accurate operation can be achieved by means of a robot auxiliary system and the technology of the robot auxiliary system.

Description

[0001] This application is a divisional application of the following patent application:

[0002] Application number: 202080077739.6

[0003] Application date: 2020.11.06

[0004] Application Title: Method and system for robotic-assisted surgery using custom bone registration guides Technical Field

[0005] Embodiments of the present invention generally relate to systems and methods for creating and using customized joint replacement surgical registration guides in joint replacement surgery. More specifically, the present invention relates to methods for creating joint replacement surgical registration guides customized for a specific patient in robot-assisted surgery, which provide 3D reference information of the patient to a surgical robot to formulate a surgical plan that can be performed by a surgical robot (including a robot fixed to a bone). Background Art

[0006] Repetitive heavy lifting, trauma, bone disease and / or arthritis can cause a patient's joints (such as the knee, hip, shoulder and ankle) to degenerate, become damaged or loose, which can lead to pain or even paralysis that cannot be effectively treated with medication or non-surgical treatments. One way to treat joint injuries in humans is with full or partial joint replacement surgery. Through joint replacement surgery, a patient's joint is replaced, rebuilt or realigned, often to relieve pain in the damaged joint. Joint damage can result in a loss or wear of cartilage in the joint area, causing friction, compression, fractures and looseness of the joint. As a result, a loss of cartilage in the joint can lead to pain and decreased joint mobility. Joint replacement surgery can help patients eliminate pain, repair damaged joints and restore function.

[0007] Joint replacement surgery typically involves removing the arthritic or damaged part of a joint and replacing it with a so-called prosthesis, a metal, plastic or ceramic device. The prosthesis or implant is designed to replicate the normal motion of a healthy joint. For example, a damaged femoral head (located at the upper end of the femur) is replaced with a metal ball that is attached to a metal stem that fits into the femur, and a plastic acetabular cup is implanted in the pelvis to replace the damaged acetabulum. In addition, a balanced joint helps improve alignment and maintain stability. Balanced ligaments help reduce joint wear and loosening. Patients with balanced joints are more likely to have increased range of motion and proprioception and reduced pain. All of these factors help reduce the need for revision surgery.

[0008] Several types of joint replacements are known, including total and partial knee replacements, total and partial hip replacements, total and partial shoulder replacements, spinal fusions, and others. Typically, joint replacement surgery involves replacing the diseased or damaged portion of a joint with a metal or plastic component that is shaped to approximate the shape of the replaced portion or that is shaped to allow for joint movement to relieve joint pain. For example, a total knee replacement may include replacing part of the femur and part of the tibia at the knee. Similar surgeries may be performed on other damaged joints, such as the hip, shoulder, elbow, and others. This general discussion of joint replacement surgery in this article is specific to total knee replacement surgery, but may also apply to joint replacement surgery for other types of joints.

[0009] In total knee replacement surgery, the damaged portion of the distal femur is removed and replaced with a metal or plastic component that is identical or similar in shape to the removed portion. The metal or plastic component can be embedded in the femur, or fixed using bone cement or other fixation systems. In addition, the proximal portion of the tibia can also be removed and replaced with a roughly flat metal or plastic component that is identical or similar in shape to the removed portion. The tibia replacement implant can be embedded in the tibia, or fixed using bone cement. In short, the femoral implant and the tibial implant cooperate to form a joint that is similar to the shape and function of the knee joint. In some examples, a plastic pad is placed between the femoral implant and the tibial implant to prevent metal-to-metal collisions when the implanted joint is used.

[0010] As described above, joint replacement surgery typically involves removing and replacing bone from the damaged portion of the joint. During the removal, portions of the bone may be cut, drilled, resurfaced, etc., to create surfaces on the bone that will mate with the corresponding implant. In a specific example of a total knee replacement, bone from the distal femur and proximal tibia may be completely removed to create relatively flat surfaces that will mate with the implant. Once the mating surface for the implant has been created on the bone, the implant may be mounted on the bone as described above.

[0011] While the above outlines joint replacement surgery, there is much to consider when performing the procedure. For example, before a joint replacement surgery, a patient may spend a month or more in one or more consultations with a physician for preoperative planning. On the one hand, the alignment of the implant within the joint with the rest of the patient's anatomy is critical to the longevity of the implant and the effectiveness of the implant. Various methods are constantly being developed to try to improve the effectiveness of joint replacement surgery and prevent or reduce postoperative complications. On the other hand, when cutting bones or resurfacing joint bones to accommodate the implant, the surgeon may do so with his freehand. While courageous, this approach is not as precise as other surgical methods. In another example, systems and methods have been developed to produce customized joint replacement osteotomy guides to help surgeons quickly and accurately make the necessary osteotomies to successfully complete the joint replacement surgery. In particular, osteotomy guides are often customized for a specific joint replacement patient to ensure that the implant fits the patient's anatomy after surgery. By using customized osteotomy guides, joint replacement surgeries can be more precise (ensuring longer implant life) and more efficient (reducing surgical time, thereby reducing the likelihood of postoperative complications).

[0012] In another example, a surgical assistance robot or other robot-like device has been developed to assist surgeons in performing joint replacement surgery. The various aspects of an approved surgical plan can be uploaded to a robotic assistance device to assist the surgeon in the operation. In some cases, the surgical assistance robot can perform osteotomy or bone surface reconstruction under the guidance of the surgeon or by automatically performing one or several items of the joint replacement surgery. In yet other instances, a variety of surgical combinations can be used to perform joint replacement surgery. For example, a surgeon can use a customized joint replacement surgery osteotomy guide to verify the cutting plane or osteotomy, while the surgical assistance robotic device completes the osteotomy or surface reconstruction. In another example, the robotic device provides navigation, while the surgeon performs the osteotomy operation freehand.

[0013] Regardless of the approach, surgery can be flawed. For example, flaws in the preoperative planning phase may involve multiple visits by the physician, obtaining patient scans or images, creating the surgical plan, the surgeon's approval of the surgical plan, and the time required to produce a custom joint replacement surgical guide. Patients may endure months of pain and discomfort while waiting for joint replacement surgery. In addition, for many medical institutions, the price of multi-million dollar robotic surgical equipment is too high. Surgeries that use one or more disposable instruments (such as disposable motion tracking devices used as consumables in some surgical robotic equipment) will further increase the cost of the operation and impose additional costs on medical institutions. The high cost and long upfront time of joint replacement surgery also cause some patients who could have benefited from it to give up surgery.

[0014] In addition, one of the goals of computer-assisted robotic surgery is to improve the accuracy and clinical effectiveness of orthopedic surgery compared to traditional methods. Current methods of robot-assisted orthopedic surgery have advantages in terms of accuracy, surgical efficiency, surgical time, minimal invasiveness, and cost-effectiveness. One of its main disadvantages compared to traditional surgery is that the technology is complex, which greatly increases the potential for surgical errors. Inexperienced surgeons may find it difficult to detect technical errors, so relying solely on robotic technicians or blindly allowing the robot to operate may result in adverse results. Other disadvantages of robot-assisted surgery compared to methods using traditional instruments include high training costs for the entire surgical team, a long learning curve for new technologies, and the high cost of the robotic surgery system itself.

[0015] It is with these and other problems in mind that aspects of the present invention have been developed. Summary of the invention

[0016] One embodiment of the present invention is to perform joint replacement surgery in the form of a robotic device. The robotic device may include a base unit (composed of a plurality of link joints, each link joint being mechanically connected to one of a plurality of actuators), a processor, and a non-transitory computer-readable decoding medium (when executed by the processor, the processor controls a plurality of actuators as required by the joint replacement surgery). The robotic device may also include a mounting device (mechanically connected to a first link joint among the plurality of link joints). The mounting device is composed of: a first configurable link (orienting the base as required by the joint replacement surgery), a mounting plate (fixed to the patient's anatomical structure by a customized registration device), a configurable osteotomy guide (mechanically connected to a second link joint among the plurality of link joints), and a second configurable link (orienting the osteotomy guide as required by the joint replacement surgery).

[0017] Another embodiment of the present invention may take the form of a method for performing joint replacement surgery. The method may include: receiving a plurality of 2D images of a patient's surgical joint; creating a customized registration guide for the patient's joint replacement surgery based on locating a plurality of mating shapes on the plurality of 2D images of the patient's joint; and mounting a robotic device on the patient's anatomical structure using the customized registration guide. The robotic device may include: a mounting device (mounted on the patient's anatomical structure), a first link joint of a base (mechanically connected to the mounting device to orient the base as required by the joint replacement surgery), and a configurable osteotomy guide (mechanically connected to a second joint of the base unit to provide osteotomy guidance as required by the joint replacement surgery). BRIEF DESCRIPTION OF THE DRAWINGS

[0018] As shown in the following drawings of specific embodiments, various features and advantages of the present invention are apparent. Please note that the drawings focus on illustrating the principles of the technical concepts and are not necessarily drawn to scale. The drawings only depict typical embodiments of the present invention, and therefore, the present invention should not be limited by the drawings.

[0019] Figure 1 It is a frontal or coronal view of the human knee joint;

[0020] Figure 2 It is a lateral or sagittal view of the human knee joint;

[0021] Figure 3 It is a transverse or axial view of a human femur;

[0022] Figure 4 is an isometric view of a total knee replacement with a fitted prosthesis;

[0023] Figure 5 is an isometric view of a medial partial compartment or unicompartmental knee replacement with a fitted prosthesis;

[0024] Figure 6 This is a diagram of the internal geometry of a total knee prosthesis; the prosthesis replaces the damaged end of the femur;

[0025] Figure 7 There are three anatomical views of the entire knee joint (coronal, axial, and sagittal);

[0026] Figure 8 are sagittal and axial views of a unicompartmental prosthesis;

[0027] Fig. 9 is a flow chart of one embodiment of a method of performing joint replacement surgery;

[0028] Fig.10 is a flow chart of one embodiment of preoperative and intraoperative robotic-assisted joint replacement surgery;

[0029] Fig.11 is an embodiment of a scanning plane; scanning is to obtain one or more scanned images of the patient's anatomical structure;

[0030] Fig.12 is an embodiment of a robot registering a femur and a tibia, the robot registering using computer navigation according to implant location and specifications;

[0031] Fig.13 is a system diagram of one embodiment of exchanging mapping information between components of a robot-assisted joint replacement surgery system;

[0032] Fig.14 is a system diagram of another embodiment of the preoperative, intraoperative and postoperative process of robot-assisted joint replacement surgery;

[0033] Fig.15 is a flow chart of another embodiment of a method for performing joint replacement surgery using one or more joint replacement surgery registered customized guides;

[0034] Fig.16 is a flow chart of another embodiment of a method for creating a custom registration guide for joint replacement surgery from one or more 2D images of a patient's joint;

[0035] Figures 17A-17E are some embodiments of custom registration guides for robotic-assisted joint replacement surgery;

[0036] Fig.18 is a system diagram of another embodiment of using a custom registration device for operation in robotic-assisted joint replacement surgery;

[0037] Fig.19 is a system diagram of one embodiment of an inertial sensor device mounted on a patient's bone for joint replacement surgery;

[0038] Fig. 20 is an embodiment of robotic registration of the femur using mechanical instruments according to implant location and specifications;

[0039] Fig.21 is an embodiment of robotic registration using a custom guide adapted to the patient's anatomy;

[0040] Fig. 22 is a perspective view of an embodiment in which a certain size incision is made according to a surgical technique and the robot is mounted on the inner side of the femur and tibia with fixation pins;

[0041] Fig.23 An embodiment of a 2-DOF single-link planar coordinate robot and a corresponding robot operation space;

[0042] Fig.24A An embodiment of a 2-DOF cylindrical coordinate robot and a corresponding robot operation space;

[0043] Fig. 24B An embodiment of a five-link robot with 6 degrees of freedom and a corresponding robot operation space;

[0044] Fig.25 It is a 2-DOF robot (see Fig.23 ) is a perspective view of an embodiment of a robot controlled by internal electromechanical and external 2-DOF robotic arms;

[0045] Fig.26 is a perspective view of one embodiment of a 2-DOF robot (see FIG. 24 ) having internal electromechanical and a 2-DOF manipulator external display;

[0046] Fig. 27is a perspective view of one embodiment of a fixture of a robot; the fixture can provide additional linear and rotational adjustments and display the adjustment values;

[0047] Fig.28 is a perspective view of one embodiment of a locking mechanism that secures the robot to the patient's anatomy via a securing plate;

[0048] Fig.29A is a perspective view of one embodiment of a 5-DOF robot secured to the distal end of a femur;

[0049] Fig.29B is a perspective view of an embodiment of a 4-DOF robot fixed to a fixation plate in close contact with the distal end of a femur;

[0050] Fig.30 is a perspective view of another embodiment of a 6-DOF robot consisting of a 2-DOF robot and a 4-DOF end effector, the robot being fixed to a fixation plate that fits closely to the patient's anatomy;

[0051] Fig.31A is an embodiment of a robot and a 2D operating space; the robot arm is mounted next to the femur, and the figure shows different configurations of the robot arm corresponding to five geometric structures inside the femoral prosthesis;

[0052] Fig.31B is an embodiment of a robot and a 2D operating space; a robotic arm is mounted at the end of a femur, and the figure shows different configurations of the robotic arm corresponding to four geometric structures inside a femoral prosthesis;

[0053] Fig.31C is an embodiment of a robot and a 2D operation space, wherein a robotic arm is mounted next to a femur, and the figure shows different configurations of the robotic arm corresponding to the continuous geometric structure inside a unicondylar femoral prosthesis;

[0054] Fig.32 is a flow chart of one embodiment of accurate positioning corresponding to the internal geometry of the prosthesis (including calibration, initialization and positioning of the robot's mechanical arm);

[0055] Fig.33 is a perspective view of an embodiment of a robot arm configured in a first position corresponding to the internal geometry of a femoral component to complete a distal osteotomy;

[0056] Fig.34 is a perspective view of an embodiment of a robot with a mechanical arm configured in a second position corresponding to the internal geometry of a femoral component to complete a posterior osteotomy;

[0057] Fig.35is a perspective view of an embodiment of a robot arm in a third position corresponding to the internal geometry of the femoral component to complete an anterior osteotomy;

[0058] Fig.36 is a perspective view of an embodiment of a robot arm in a fourth position corresponding to the internal geometry of a femoral component to complete an anterior oblique osteotomy;

[0059] Fig.37 is a perspective view of an embodiment of a robot arm in a fifth position corresponding to the internal geometry of the femoral component to complete the posterior oblique osteotomy

[0060] Fig.38 is a perspective view of an embodiment of a configuration of a robotic manipulator, the configuration of the manipulator corresponding to the internal geometry of a unicondylar femoral component for bone surface reconstruction;

[0061] Fig.39 An example of intraoperative soft tissue ligament balance is given. The knee extension gap is asymmetrical, and a 5-DOF robot is used to determine the ligament tension and correct angle.

[0062] Fig.40 An example is used to illustrate the balance of soft tissue ligaments during surgery. The knee extension gap is asymmetric, and a 5-DOF robot is used to determine the ligament tension and correct angle.

[0063] Fig.41 An example is used to illustrate the balance of soft tissue ligaments during surgery. The knee joint flexion gap is asymmetric, and a 5-DOF robot is used to determine the ligament tension and correct angle.

[0064] Fig.42A An example is used to illustrate the balance of soft tissue ligaments during surgery. The knee joint extension gap is asymmetric, and a 6-DOF robot is used to determine the ligament tension and correct angle.

[0065] Figures 42B-42D An example is used to illustrate the use of a 3-DOF robot and a scissor jack to achieve soft tissue ligament balancing during surgery; Fig.42E It is a 2-DOF robot 4240 (see Fig.42C ) is a side view; Fig.42F The equilibrium state with medial and lateral ligament tensions both at 60 Newtons is shown;

[0066] Fig.43 It is a perspective view of an embodiment of a knee joint uniaxial rotation to achieve dynamic balance of soft tissue ligaments;

[0067] Fig.44 is a perspective view of one embodiment of a robotic assisted surgical system in an operating room; the surgical system utilizes a computer system and two-way communications to display real-time information;

[0068] Fig.45 The flowchart of a computing system for implementing an embodiment of the present invention is shown by way of example. DETAILED DESCRIPTION

[0069] The present invention relates to systems and methods for bone-mounted micro-robotic assisted surgical systems for treating joint diseases. For ease of description, the current disclosure focuses on knee surgery, but it can also be applied to other joint surgeries (such as hip, shoulder, elbow and ankle), as well as spinal surgery (such as fusion). Some common types of knee surgery are as follows:

[0070] Total knee replacement surgery

[0071] Partial or unicompartmental or bicompartmental knee replacement surgery

[0072] Patello-femoral resurfacing surgery

[0073] Osteotomy

[0074] Knee revision surgery

[0075] The present invention discloses the following aspects: systems, methods, computing devices, etc. for performing joint replacement surgery using a customized registration guide adapted to the patient's anatomical structure, and providing registration information to a surgical assisted robotic device. Through the system and process described herein, a faster, more economical and more accurate robotic assisted joint replacement surgery can be performed using a registration guide. The special feature is that a customized registration guide can be created from several 2D images of the patient's anatomical structure. The registration guide has one or more mating surfaces adapted to a specific position on the bone of the patient's damaged joint. In addition, because the creation of the registration guide is based on the patient's scan imaging (excluding instructions related to osteotomy planes or surface reconstruction information), it can be created before the surgical plan is approved. During the joint replacement surgery, the registration guide can be assembled to the patient's bone by a surgeon or a robotic device, and the position of the registration guide in 3D space can be provided to the robotic device. Therefore, the robotic device can determine the position of the patient's anatomical structure without the need for a registration process (the registration process requires a probe or surgeon to locate a specific position on the patient's bone to provide the robotic device with the patient's positioning). More precisely, the registration device can be connected to the robotic device, and since the size of the registration device is known, the position and orientation of the patient's anatomy is also known. The patient's anatomical position can then be mapped to the surgical plan, and the robotic device performs the osteotomy and / or resurfacing.

[0076] In another embodiment, a robot system fixed to a bone performs full and partial knee surgery osteotomy, and then replaces the cut bone with the same joint prosthesis. In this operation, a customized registration device can be used for robot fixation. Compared with a stand-alone or bed-mounted surgical robot, the advantage of a robot-assisted surgery system mounted on a bone is that once intraoperative registration is completed, motion tracking is not required because the robot moves with the patient's joints. In addition, compared with a general-purpose robot that can operate in different operating spaces, the size and complexity of the robot designed for the specific operating space of each joint surgery can be reduced. There are many reasons why smaller and more economical robot-assisted surgery systems are attractive, including cost, ease of use, a faster learning curve, less training required for the entire surgical team, and not being limited by space in small operating rooms (such as outpatient surgery centers).

[0077] In general, mounting the robot on the patient's anatomy based on the size and location of the implant can be accomplished using a variety of techniques, including but not limited to mechanical instruments, computer navigation, or patient-specific fixtures. For imaging systems that use X-rays, MRI and CT scans or other 2D images preoperatively, the registration process may include identifying bone landmarks on the 2D image or virtual surface of the bone model. Intraoperatively, computer navigation or patient-specific guides (several physical contact points) can be used to register the robot with the actual patient's bones in the imaging data, and can also be used to register the patient's position and / or orientation relative to the independent robotic device in the surgical space. For non-imaging systems, the surgeon can use computer navigation systems, sensor instruments, or mechanical instruments to identify bone landmarks during surgery. For both imaging systems and non-imaging systems, the registration process provides the relative position and relative orientation of the robot to the patient's position, orientation, and / or anatomical axes in a 3D coordinate system (X, Y, Z).

[0078] Another aspect of the present invention is that one or more inertial sensors (which can be used with a robot system mounted on the bone, or independently of the robot system) can be used to track patient movement. Other aspects of the present invention also include a mechanical fixture with a locking system and / or a mechanical protractor for intraoperative soft tissue ligament balance and leg alignment measurement. For example, after the implant position has been determined, static and / or dynamic soft tissue balance can be created. In static soft tissue gap balance, the gap imbalance is measured by fully extending (straightening) and bending the knee joint by about 90° (the angle between the femoral shaft and the tibial shaft). In dynamic soft tissue gap balance, the common femoral rotation axis between the femoral and tibial joint lines and the patellofemoral joint line can be determined, the movement is simulated according to the kinematic principles of the knee joint, and real-time adjustments are made to obtain correct knee joint movement and soft tissue balance. Subsequently, the robotic device recreates the ideal bone spacing (extension and flexion gaps), and the ideal bone spacing and implant specifications can be used to correct the osteotomy during implantation.

[0079] Another aspect of the present invention is that a robotic-assisted surgical system can be provided for use during joint surgery. The system may include a robotic device, a computer, a transceiver, a monitor and / or other devices, such as power tools, monitoring equipment or a robot. The computer portion of the system can provide real-time data and communication to the robotic device during surgery. However, for some robots, these are not necessary, such as robots mounted on bones, or stand-alone devices with internal microprocessors, embedded firmware, sensors, memory and power supplies.

[0080] In some cases, joint replacement surgery can be performed without the use of optical locators due to the use of the registration device described in this article, thereby reducing surgical costs for patients and medical institutions. The registration device has higher registration accuracy than previous registrations. In addition, one or more motion sensors can be associated with the patient's anatomical structure in a fixed manner or other manner, and the patient's movement can be wirelessly transmitted to the robotic device to adjust the set position and direction of the osteotomy plane relative to the patient's bones. Motion sensors (such as one or more inertial sensors), due to their high sensitivity, may be able to monitor the patient's movement more accurately than optical sensors, thereby further improving the effectiveness of joint replacement surgery. Registration guides and inertial sensors can be used for any type of joint replacement surgery, including knee, hip, shoulder, spine and other surgeries. In some cases, a virtual reality system can be incorporated into the system to help surgeons complete one or more parts of joint replacement surgery. These and all other joint replacement surgeries can benefit from the systems and methods described herein.

[0081] The above is a fairly general introduction to some of the features of methods and systems for robotic-assisted surgery systems using a customized joint replacement surgery registration device. Other incidental features of methods and systems for robotic-assisted surgery systems are also discussed herein, such as clamping and locking systems, sensors (force and inertial sensors) for robotic registration, real-time monitoring and communication, and intraoperative knee joint modeling for soft tissue ligament balance and limb alignment measurement. In this regard, patent applications for methods and systems for robotic-assisted surgery systems should certainly not be limited to the structural details and details of the component configurations described or illustrated below. The methods and systems can be used in other aspects and can be practiced and implemented in different ways. It should also be understood that the terms and terminology used herein are for descriptive purposes only and should not be considered limiting.

[0082] As mentioned above, the present invention relates to methods and systems of robot-assisted surgery systems. To facilitate the following discussion, the anatomical structure of the human knee joint is briefly described. As mentioned above, the present invention can be applied to orthopedic surgery at any part of the patient's joint. However, for ease of understanding, this article only takes the knee joint as an example to discuss the surgery and embodiments related to the present invention.

[0083] Figure 1 Shown is a coronal or frontal view 100 of a patient's knee joint, including a femur 102 and a tibia 110 interconnected by four ligaments. These ligaments are called the medial collateral ligament (MCL) 103, the lateral collateral ligament (LCL) 105, the anterior cruciate ligament (ACL) 107, and the posterior cruciate ligament (PCL) 109. Other soft tissues and the knee capsule, which is filled with body fluid and fat, surround the knee joint. The ligaments and patellar tendon 202 provide stability to the knee joint during standing, walking, and running. The distal end of the femur 102 has thicker cartilage (the cartilage of a healthy adult knee is typically 1-7 mm thick) that forms a bearing surface for the medial condyle 106, lateral condyle 104, and patellar groove 108. Correspondingly, the proximal end of the tibia 110 has a medial platform 116 and a lateral platform 114, and also has thicker cartilage (the cartilage of a healthy adult knee joint is usually 3-7 mm thick), which acts as a shock absorber together with the meniscus and the bearing surface. The fibula 118 provides further support to the lateral side of the tibia, providing additional stability in terms of load-bearing, bouncing, damping and shock absorption. In addition, the lateral collateral ligament (LCL) is connected to the head of the fibula 118, and has 1-2 mm of slack or looseness, so that the knee joint can rotate (rotate on the axis) and slide more freely without any restraint or resistance. If the knee cartilage is worn, pain will occur when the nerve endings of the femur 102 and the tibia 110 touch each other.

[0084] Figure 2 Shown is a sagittal or side view 200 of a patient's knee joint 206, including the outside of the femur 201 and the outside of the tibia 203. The patella 202 is located in front of the femur 201 and is in an extended state. When the knee joint is bent, the patella 202 moves along the patellar groove 108 and stops near the center of the knee joint. The knee joint is surrounded by tissues such as muscles, fat, ligaments, and body fluids that fill the joint cavity. The wall layer in the capsule allows the knee joint to fully extend and flex. The posterior condyle 205 has cartilage 204, which is oval in shape, so that the knee joint can be flexed and extended easily. In a healthy knee joint, the bone / cartilage on the surface of the femur 201, tibia 203 and patella 202 provides the ligament tension and stability required for knee joint movement. However, when the cartilage surface is damaged or worn, the knee joint may be painful, loose and / or unstable. In some cases, partial or complete knee replacement can be performed to restore knee joint stability and soft tissue ligament balance to eliminate pain. Restoring balance and stability of the knee through surgery is often critical, which can prolong the life of the prosthesis and avoid the need for further anesthesia, surgery, and soft tissue revision.

[0085] Figure 3An axial or transverse view 300 of a patient's knee joint is shown, including the patellar groove 301, the medial condyle 302, and the lateral condyle 303. The lateral collateral ligament (LCL) 105 is connected to the lateral epicondyle 306, and the medial collateral ligament (MCL) 103 is connected to the medial epicondyle 305. The anterior cruciate ligament (ACL) 107 and the posterior cruciate ligament (PCL) 109 are connected to the inside of the femoral intercondylar notch 304 (located above the medial condyle 302 and lateral condyle 303 in a dome shape) in a cruciate formation, which tightens the knee joint during extension and flexion. The medial and lateral bony prominences of the femur (epicondyle) can be used to establish an axis of rotation, called the transepicondylar axis 307. Other axes can also be defined, such as the anterior-posterior (AP) axis 309, patellofemoral and posterior epicondylar axes 308. These axes are used to help the surgeon determine the correct position and orientation of the prosthesis during total knee replacement surgery. Malrotation of the knee prosthesis may lead to loss of knee flexion, pain caused by ligament imbalance, and premature failure requiring revision surgery. Therefore, it is beneficial to simulate flexion and extension movements to balance the soft tissues around the knee and correct the position and size of the implant.

[0086] Figure 4 It is an isometric view 400 of a patient's knee joint 405 and a matching prosthesis 402 after total knee replacement surgery. During the operation, the bone and cartilage at the ends of the femur 404 and tibia 403 are removed and replaced with metal and plastic components 402. In addition, the bone and cartilage 401 of the patella can also be replaced with metal and / or plastic components. Typically, the prosthesis 402 is glued or press-fitted to the bone for a long time. The purpose of total knee replacement surgery is to replace the worn cartilage / bone surface with the prosthesis 402, remove nerve endings from the femur 404 and tibia 403, and relieve pain. Osteotomy is performed using an oscillating saw and an osteotomy guide according to the internal geometry of the prosthesis 402. In order to retain as much healthy bone as possible while also maintaining the structural integrity and functionality (shape) of the knee joint, the amount of bone resection should be as small as possible. For standard off-the-shelf prostheses, each specification of the prosthesis has its corresponding surgical instrument, which is expensive to manufacture and requires a large amount of inventory to be maintained, so the division of its specifications is limited. For example, in order to perform the least amount of bone resection as possible, implants of different brands and different specifications (height and width) require different osteotomy guides that match them. For example, unlike implants that are specially designed or customized for each patient's knee joint, most current knee implant systems have about 8-12 different specifications to cover the entire patient population.

[0087] Figure 5It is an isometric view 500 of a partial or unicompartmental knee replacement in the medial compartment and its matching prosthesis 502 (metal and plastic components). Depending on the location of the damaged knee joint, knee replacements in other compartments can also be performed. For example, the lateral compartment can include the lateral femoral condyle 501 and the lateral tibial plateau 503. Other two compartments, such as any combination of the patellar groove 301 and the medial condyle 302 or lateral condyle 303, or any combination of the patella, medial condyle and lateral condyle, can be replaced. The three compartment replacement surgery is the same as that of the total knee. These partial replacement surgeries have the same purpose as total knee replacement, which is to only remove the worn bone and cartilage and retain as much healthy bone and cartilage as possible for future revision or total knee replacement.

[0088] Figure 6 Shown is a total knee prosthesis 607 (its internal geometry can be seen in the figure) replacing the distal end of the damaged femur 601. Figure 4 As shown and described above, the femoral and tibial implants are 3D. For ease of description, the internal geometry of the prosthesis 607 is represented by Figure 6 ; however, in reality, the prosthesis may consist of a series of continuous planes. In one example, in order to minimize the amount of bone resection and take into account the severe cartilage / bone loss, the internal geometry and thickness of the implant are determined by five cutting planes: the distal or initial plane 604, the posterior plane 606, the anterior plane 602, the oblique posterior plane 605, and the oblique anterior plane 603. For most implant brands, the number of internal geometries may be the same, but the size (height and width) of 607 varies from specification to specification. For example, the height of the distal plane 604 may vary from specification to specification, while all other internal planes 602, 603, 605 and 606 may remain unchanged. In one embodiment, the internal geometry of the prosthesis 607 may be different for different specifications. For example, if the implant is customized, its internal geometry and thickness may be more or less, and it has a smooth continuous contour that matches the round shape of the distal end of the femur 601. In other embodiments, the internal geometry and specifications of implants from different brands are different. Therefore, conventional osteotomy instruments adapted to the internal geometry of the implant may be brand specific.

[0089] Figure 7 701, axial plane 702, and sagittal plane 703. In some cases, the distal femoral osteotomy in conjunction with the internal geometry of the prosthesis determines the position and orientation of the implant in each plane. For example, in the coronal plane 701, plane 705 (i.e., Figure 6 The distal line 604 in the axial plane 702 determines the yaw (varus / valgus rotation) angle and superior / inferior position of the implant relative to the center of the knee joint (defined by line 704). Similarly, in the axial plane 702, plane 707 (i.e. Figure 6The posterior line 606 in the sagittal plane 704 determines the rotation (internal rotation / external rotation) angle and anteroposterior position of the implant relative to the center of the knee joint (defined by line 707). Finally, in the sagittal plane 703, plane 709 (i.e. Figure 6 The distal line 604 in FIG. 7 ) determines the pitch (flexion / extension rotation) angle and up / down position of the implant relative to the center of the knee joint (defined by line 708). The remaining geometry: the anterior plane 602, the oblique anterior plane 603, and the oblique posterior plane 605 are determined by the implant position, which in turn is determined by the distal plane, internal / external rotation, and implant size.

[0090] Figure 8 802 (with continuous internal geometry 803) to replace the damaged bone / cartilage medial compartment 805 of the femur 801. To match the shape of the femoral condyle 205, the unicompartmental prosthesis has a generally oval geometry 803 connected to a linear posterior cutout 804. The partial knee implant 802 is more suitable for patients with less cartilage / bone damage. In order to maintain the joint line of the femur (see Figure 2 The amount of cartilage / bone removed should be appropriate to the thickness of the implant 802, as shown in Figure 206. In addition, the position and orientation of the implant in the sagittal plane 802 and the axial plane 806 should match. In one embodiment, the lateral compartment of the knee joint is damaged and can be replaced with a unicompartmental prosthesis. Another embodiment is a bilateral unicompartmental replacement (both the medial and lateral condyles are replaced with unicompartmental prostheses).

[0091] As mentioned above, joint replacement surgery implants a prosthesis to repair a patient's damaged joint. Fig. 9 Flowchart of method 900 for joint replacement surgery using the embodiments described herein. In summary, method 900 provides a method for robot-assisted joint replacement surgery and repairing damaged joints. As described below, implementation of method 900 can be accomplished by many systems or devices. Method 900 can be implemented with more or fewer steps, and can be accomplished by the above or additional systems and devices. Fig.10 The preoperative and intraoperative procedures of the robot-assisted joint replacement surgery involved in method 900 are described, including some devices and systems for implementing the surgical method 900.

[0092] like Fig.10As shown, the preoperative part may include a data acquisition stage 1002, an image segmentation stage 1004, and a surgical planning stage 1006. The intraoperative part may include a registration stage 1008 and the use of a surgical robot device 1010. The various stages of the process will be described in detail below. In the data acquisition stage 1002 (see operation 902 in method 900), one or more scan images of the patient, especially the damaged joint, are acquired through an imaging device or system. In one embodiment, one or more computed tomography (CT) scans, one or more magnetic resonance imaging (MRI) scans, one or more X-ray scans, or any other type of in vivo images of the patient are acquired through a corresponding imaging device or system. The patient's images include 2D or 3D images. In a particular example, a series of 2D images of the surgical joint can be obtained or received through a network connection. The 2D images of the patient's joints can be obtained from several parts of the joints from an imaging device (such as an X-ray machine or a magnetic resonance MRI imager). For example, Fig.11 An embodiment of obtaining a 2D image of a patient's knee joint 1106 is shown. Specifically, the patient's knee joint 1106 (including part of the femur 1102 and the tibia 1104) is scanned with an MRI knee joint circle layer to create several 2D knee joint circle layer MRI images of the patient's knee joint. In one embodiment, the 2D image 1108 of the knee joint includes several images of the knee joint scanned along the coronal plane 1108a, along the axial plane 1108b and / or along the sagittal plane 1108c. In other embodiments, the 2D image can be any combination of coronal, sagittal and / or axial views. In one embodiment, the spacing of the knee joint MRI 2D circle layer scanning can be within the range of about 1-6mm, and the spacing can vary with the position. For example, the interval of the coronal image slice 1108a can be 2mm, and the interval of the axial image slice 1108b can be 6mm.

[0093] The embodiments herein are described by obtaining images using an MRI imager, but in other embodiments, images may also be obtained by computer tomography (CT), X-ray or other medical imaging methods and systems. In addition, the present invention describes obtaining knee joint scan images, but 2D images of any joint or other part of the patient's body (e.g., the patient's ankle, hip, shoulder, etc.) may also be obtained.

[0094] Once the 2D images of the relevant joints are obtained, they are input into a computing device and processed in the image segmentation stage 1004. For example, Fig. 9In operation 904 of method 900, the computing device may receive the acquired patient images or other data through any form of electronic communication with the imaging device. In a particular example, the 2D images may be acquired by the imaging device (e.g., an MRI imager) and sent to a website accessible by the computing device. In general, the 2D images may be acquired from the imager in any manner for further processing by the computing device. Once received, the 2D images may be stored in a computer-readable medium for further processing by the computing device.

[0095] Image data processing involves segmentation by region, where images of each region of the patient's bone are used to create (or reconstruct) a 3D model of the patient's bone within a collection of images. For example, a technician may use a computing device to provide thousands of landmarks within each image to outline the external shape of a bone such as the femur or tibia within the patient's knee joint. This approach typically uses a dense 3D grid of points to accurately represent the bone surface, especially surfaces with sharp or acute angles and very small radii of curvature. However, this approach has several disadvantages: (1) This approach is time-consuming, typically requiring 4-20 hours of intensive numerical computation to create and check the accuracy of the grid point coordinates for a single surface; (2) The long time required to process a single surface limits the use of this approach in large-scale manufacturing of custom or semi-custom devices; (3) This approach may introduce geometric errors, including closure errors; (4) Because the grid points are closely spaced, high-order polynomials are used, and the entire segmentation process can cause undesirable "ripples" in the mathematical surface; and (5) A large number of MRI slices must be generated and analyzed. However, since many image-based, robotic-assisted joint replacement procedures often require a 3D model of the patient’s anatomy, segmentation of the patient images is still required.

[0096] After the patient images are segmented and the 3D model of the patient's anatomy is drawn, the joint replacement surgery 1000 can enter the surgical planning stage 1006. In the surgical planning stage 1006, the surgeon reviews the patient scans and / or the 3D model of the patient's joints and creates and / or approves the osteotomy or surface reconstruction plan for the joint replacement surgery (in operation 906 of method 900). In some cases, the surgeon may identify or determine the location and direction of the osteotomy line on the 3D model of the patient's bones. This information can be stored with the 3D model of the bones as an identification of the approved osteotomy line or surface reconstruction for the patient's joint replacement surgery.

[0097] In some surgeries, a traditional osteotomy guide (or osteotomy jig) may be used to assist the surgeon or robotic-assisted device in executing an approved surgical plan. The osteotomy jig used in joint replacement surgery can be secured to the bones of the joint in a variety of ways. When a standard osteotomy jig (a non-customized osteotomy jig that does not take into account the specific patient anatomy) is used, the surgeon typically needs to position the osteotomy line in the correct position when securing it. As you can imagine, the effectiveness of such a universal osteotomy jig varies greatly, depending primarily on the surgeon’s experience and technique. Customized osteotomy jigs, on the other hand, are designed specifically for a specific patient’s bones, reducing the chances that the osteotomy jig will not fit the patient’s knee properly.

[0098] Customization of osteotomy jigs for joint replacement surgery may vary from surgery to surgery. As a simple example, customization may include simply selecting one of a set of universal osteotomy jigs of different specifications to match the 3D model of the patient's joint anatomy. Alternatively, a customized osteotomy jig for joint replacement surgery may be fixed to the bone with a mating surface that is completely opposite to the surface of the bone in the joint. Regardless of whether the osteotomy jig used is customized, the design of the jig should ensure that it provides the correct position and orientation on the bone of the affected joint so that the area can be treated accurately, safely, and quickly.

[0099] In order to create an osteotomy guide (e.g., in operation 908 of method 900), the patient and surgical data or information may be further processed by a computing device. For example, the segmentation information used to construct the 3D model may be used to create an osteotomy guide surface that is identical to and adapted to the 3D model. In this way, the osteotomy fixture may be fixed to the bone of the joint through the mating surface. The osteotomy fixture may be provided with a cutting guide or cutting line for guiding the surgeon or robotic device to operate the surgical saw. For example, during surgery, the surgeon may insert or pass the saw blade device through the knife groove to perform a partial osteotomy. In this way, the end of the joint bone is osteotomized or reconstructed based on the customized or non-customized guide used during the operation. A customized osteotomy guide may be created by 3D printing based on the patient model and the approved surgical plan. The specific uses of the customized guide for robotic-assisted surgery in terms of registration of the patient's anatomical structure with the robotic surgical device, connection of the robotic surgical device with the patient's anatomical structure, and positioning of the patient in the surgical environment will be described in more detail below.

[0100] In some cases, the preoperative process 1000 may stop at the stage of approval of the surgical plan, creation of the osteotomy guide, etc. The patient is prepared for the surgery and enters the surgical stage of the joint replacement. After removing the tissue around the joint, the surgeon can provide several reference points on the surface of the patient's bones to the robotic surgical assistance device when operating 910. The patient's anatomy can be registered to the robotic device in a variety of ways, but the method commonly used is: the patient's anatomy is located in 3D space, and the robotic device maps the patient's relative position and orientation to itself. Fig.12By way of example, using a computer navigation system, a robotic device may be provided with a reflective cursor 1210 and a probe 1208 (with known offsets and diameters) to register a bone landmark of interest. A stereo sensor 1212 may use infrared (IR) 1202 to monitor the reflective cursor 1210 (with a unique configuration) to provide compensation for calculating position and orientation. For example, by triangulating the reflective cursor 1210 as monitored by the IR sensor 1212, the spatial position of the landmark may be determined. Knowing the dimensions of the probe 1210 through the computer navigation system, the robotic device or a corresponding computer navigation system may calculate the positional relationship between the probe tip and the cursor of the probe 1210. In some embodiments, the cursors 1204 and 1211 may be fixed to the patient's anatomy to track the patient's movements throughout. The use of a computer navigation system in assembling a surgical robot 1201 mounted on a bone to a patient's anatomy will be described in more detail below.

[0101] In some cases, in order to calculate the 3D position of the desired point (e.g., the center of the knee, the lowest point of the medial and lateral condyles, the landmark points on the medial and lateral sides of the femur, the anterior cortical point of the lateral ridge, etc.), the robotic device may provide the surgeon with one or more position instructions for placing a probe device on the patient's bone. In addition, by connecting the cursor 1211 to the femur, rotating the knee joint, and performing circular and linear motions, the hip joint center can be estimated using a spherical contour with a certain center and radius. In other instances, the surgeon may fix the probe device 1208 to different points on the patient's bone and provide the robotic device with the identification of the relevant points on the patient's anatomical structure. Fig. 9 As shown in operation 912 of method 900, the requested or provided position corresponds to the 3D model of the patient's joint so that the robotic device can map the registration information to the model. Fig.10 As shown in stage 1010, once the patient position and orientation are mapped to the patient 3D model, the robotic surgical device can perform osteotomy according to the surgical plan approved in operation 914. The robotic device can operate independently according to the surgical plan or perform osteotomy or surface reconstruction under the guidance of the surgeon. After the operation is completed, the surgeon or other institutions can analyze and summarize the surgical results for future use.

[0102] Despite the high accuracy of surgical assistance using robotic devices, the above-mentioned surgery may still have several disadvantages. In addition to the long preoperative preparation and the high cost of robotic-assisted equipment, the registration process of mapping the patient's bones to the 3D model is time-consuming and error-prone. For example, in order to accurately map during registration, the surgeon may be required to provide up to 50 or so verification points on the patient's bones. Moreover, some registration points may require the surgeon to pierce the articular cartilage or other soft tissue to locate the reference point. In addition, the accuracy of the registration process depends on the accuracy of the 3D model of the patient's joint. If the model is inaccurate due to segmentation or calculation errors, it will also cause inaccurate registration process, which will ultimately lead to increased errors in osteotomy.

[0103] Furthermore, mapping information must be shared between several components of the system (including the patient, the robotic device, and / or the computer navigation system) to ensure accurate bone cutting during joint replacement surgery. Fig.13 1300 is a system diagram of an embodiment of mapping information exchange between components of a robot-assisted joint replacement surgery system. As described above, a joint replacement surgery may include a surgically assisted robotic device 1304 that performs one or more cuts, osteotomies, surface reconstruction, etc. on a patient 1306. To determine the osteotomy position and direction, the robotic device 1304 maps the registration input to the patient's anatomical model to determine the position and direction of the patient's anatomy in 3D space. Specifically, a 3D model of the patient's joint can be uploaded to a computing device 1302 (associated with or communicating with the robotic device 1304). The 3D model can be created through the above-mentioned imaging and segmentation steps. Through the patient model, the robotic device 1304 can know the surgical plan and the location of the osteotomy or reconstruction surface on the patient's bones, but cannot find the position and / or direction of the patient 1306.

[0104] Positioning the relative position of the patient 1306 and the robotic device 1304 can be achieved through registration. Specifically, during the registration process, the robotic device 1304 and / or the computing device 1302 can use an optical locator 1308 to determine the position and orientation of the patient 1306. The surgeon can use a probe tool, a manual coordinate measuring machine (CMM), or other registration tools to locate various points of the bare bone of the patient's joint 1306. The surgeon places the registration tool on the anatomical structure of the patient 1306, and the optical locator 1308 can track or mark the position of the cursor on the registration tool in space. With the help of the computing device 1302 or the robotic device 1304, the relative spatial position of each registration point and the optical locator 1306 can correspond to the same position on the patient's bone model. Since the surgical plan is formulated based on the scanned imaging, the registration points of the patient's bones are mapped to the 3D model, and the computing device 1302 and / or the robotic device 1304 can determine the approximate position of the patient's anatomical structure. Through modeling and registration, the robotic device 1304 can calculate or determine the position and orientation of the osteotomy or reconstruction surface of the surgical plan. Once determined, the robotic device 1304 can assist the surgeon in the bone cutting or resurfacing portion of the surgery. Any inaccuracy in the shared mapping information due to patient image segmentation, segmentation-based modeling, registration of the patient's anatomy, mapping to model registration points, patient movement, etc., may result in inaccurate bone cutting and / or resurfacing, surgical failure, or unsatisfactory results.

[0105] Tracking the movement of the patient during surgery is also part of robot-assisted joint replacement surgery. As described above, the registration process provides the robot device 1304 with an estimated position of the mapping of the patient's spatial position and direction. However, in some cases, the patient's anatomical structure may move or be moved during surgery. In order to track the patient's movement, one or more cursors are installed on or near the surgical joint. The optical locator 1308 can track the movement of the cursor during surgery and provide the monitored movement identification to the computing device 1302 or the robotic device 1304. The computing device 1302 and / or the robotic device 1304 can adjust the mapping of the patient's position to the 3D model to compensate for the patient's movement. However, tracking the patient's movement in this way may introduce more errors during surgery. For example, the optical locator 406 needs to determine when the cursor moves through an unobstructed line of sight. However, in many cases, the surgeon, surgical equipment or other objects may interfere with the line of sight between the optical locator 406 and the cursor, causing some of the patient's movements to be ignored. In addition, the optical locator 1306 may also have difficulty monitoring the patient's movement along the line of sight. Other inaccuracies, such as the resolution of the camera used and / or foreign matter on the camera lens, may negatively impact the accuracy of monitoring patient movement. These inaccuracies can also lead to inaccurate osteotomies and / or resurfacing, surgical failures, or suboptimal outcomes.

[0106] In order to solve the undesirable results of robot-assisted joint replacement surgery, Fig.14 A system 1400 of another embodiment of robot-assisted joint replacement surgery (including pre-operative, intra-operative and post-operative) is provided. Fig.14 The system 1400 in FIG. 1 shows various components and operations for performing joint replacement surgery, which addresses some of the shortcomings of other robotic-assisted joint replacement surgeries. Several operations of the system 1400 are shown in FIG. Fig.15 Specifically, Fig.15 For use in another embodiment Fig.14 Flowchart of method 1500 for performing joint replacement surgery using system 1400. The operation of method 1500 may be performed by Fig.14 The method 1500 is performed by components of the system 1400 shown in FIG. 1 and may also be performed by other components not shown. As described in more detail below, in one example, the method 1500 registers the patient's position to the robotic device using one or more customized registration guides.

[0107] Similar to the above, Fig.14 The system 1400 includes a patient imaging device to obtain several or several series of images of the patient's anatomical structure (e.g., a damaged joint). As described above, in operation 1502, the image can be obtained via an imaging device or system (e.g., a CT scanner, an MRI scanner, an X-ray scanner, or any other type of imaging device). Also similar to the above, the surgeon can use imaging data or scanned images to create or approve a surgical plan for a joint replacement surgery. The preoperative plan may include the surgeon reviewing the patient's scanned images and selecting one or several steps of the joint replacement surgery based on the scanned images, such as: determining the osteotomy plane position of the patient's joint, removing the damaged part, assembling the joint replacement device, formulating a surface reconstruction plan for the damaged bone, determining the implant position and direction within the joint, etc. In some cases, the preoperative plan 1406 may include sending the scanned images or other patient data to a computing device via a network. The surgeon can view the images on the computing device and provide instructions or other information for the intended surgery through the computing system.

[0108] While the surgeon is performing preoperative planning 1406, a bone registration device 1404 can be created based on the patient scan imaging in operation 1504. Similar to the above-mentioned customized osteotomy guide, the creation of the bone registration device 1404 can be based on the segmentation processing of the patient scan imaging, or it can be based on the 3D model of the patient's joint. However, in other instances, a customized bone registration device 1404 can be created from a 2D scan image or imaging of the patient. In particular, the customized joint replacement registration device 1404 also requires the support of systems, methods, computer programs, manufacturing processes, etc. Specifically, this is a method for creating a customized joint replacement registration device 1404 from one or more 2D images of a patient's joint for joint replacement surgery. The method includes receiving a 2D image of the joint from an imaging device, reformatting the image, and creating a template for a customized registration device 1404 from the image. Typically, through a computing device, one or more electronic marks can be made on one or more 2D image series of a patient's joint. These electronic identifiers on the 2D image series correspond to the identifiers of the patient's operated joint. Once the computing device creates a template for the registration device 1404 using one or more electronic markers on the 2D image, the computing device creates a tool path or milling program. Then, a milling machine or 3D printer uses a special tool path or milling program to process the registration guide. The registration device 1404 is customized based on the identifiable markers in the series of several 2D images of these patient joints. Moreover, the operation does not require the creation of customized feature points of the registration device 1404 based on the 3D model of the patient's anatomical structure. The identifiable marks in the 2D image correspond one-to-one to the feature points of the joint anatomy, and the registration device 1404 contacts these feature points with one or more matching shapes to achieve customization. In addition, since there is no need to create a 3D model, customized registration guides can be created faster and more efficiently than previous customization methods.

[0109] A specific method for creating a customized joint replacement surgical registration guide from 2D images is described in U.S. Patent No. 10,139,807, which is incorporated herein in its entirety. The method described herein eliminates the entire segmentation procedure and 3D anatomical modeling of the associated bone surface and replaces it with a new method of acquiring data. For example: only 6 MRI 2D images are required, and only about 12 contact points need to be selected on an anatomical surface (e.g., the posterior femur) (with flexibility in choosing between the bone surface and the instrument (guide) adapted thereto). Replacing the entire segmentation procedure of thousands of grid points with this simpler and faster method allows for faster creation of a customized registration device 1404.

[0110] Fig.16 The method 1600 of the flowchart shown shows a method for creating a custom registration guide for joint replacement surgery (such as total knee replacement). Specifically, Fig.16A method for creating a custom registration guide based on a 2D image of the patient's joint anatomy is described. Although there may be more or fewer procedures involved in creating a custom registration guide for joint replacement surgery, Fig.16 provides an introduction to such procedures using 2D images of the patient's joints.

[0111] Beginning at operation 1602, images or scans of the patient's anatomical structure may be received over a network. In some cases, the images may include a series of 2D images of a plurality of locations of the patient's joint. Figure 3 ) can be obtained from an imaging device (such as an X-ray machine, CT machine or MRI machine). The figure shows only a scan of the knee joint, and 2D images of any joint or part of the patient's body (such as ankles, hips, shoulders, spine, etc.) can also be obtained by scanning. Once the 2D image of the joint is obtained, it will be input into the computing device for processing, and the step of creating a joint replacement surgery registration guide in operation 1604 will be further performed. The computing device can receive the image from the imaging device through any form of electronic communication. In a special case, the 2D image can be obtained by an imaging device (such as an MRI machine) and transmitted to a website accessible by the computing device. In short, the 2D image can be obtained from the imaging device in any way and further processed by the computing device. After the 2D image is received, it can be stored in a computer-readable medium or cloud storage for further processing by the computing device.

[0112] In operation 1606, the 2D image of the joint is reformatted, the image in the machine-defined coordinate system is converted to an image that approximates the true anatomical coordinate system, and / or one or more landmarks on the patient's joint that match the contact points and contact surfaces of the customized registration guide are identified. Typically, the true anatomical coordinates of the patient's joint are equivalent to the natural alignment of the joint before damage. For example, the true anatomical alignment of the patient's knee joint may correspond to an axial plane parallel to the ground passing through the center of the knee joint when the patient walks. Of course, it is not necessary to reformat the 2D image to obtain an image of the true anatomical alignment of the knee joint. To be precise, the reformatting of the image may approximate the true anatomical alignment of the knee joint. The image of the joint displayed in the true anatomical coordinate system can be used to create a guide and help the surgeon confirm the installation of the guide in the damaged joint.

[0113] In one embodiment, an operator of a computing device can view the images using a monitor or other interface of the computing device. Using a software program executed by the computing device, the operator can view the 2D images and annotate at least one of the 2D images with one or more electronic identifiers. The electronic identifiers correspond to one or more reference points in the images, enabling the computing device to process and reformat the images, and / or identify feature points or landmarks in the 2D images of the patient's anatomy that correspond to the contact surface of the custom registration guide.

[0114] In another embodiment, a program executed by a computing device may obtain a 2D image, determine one or more reference points within the image, reformat the image to correspond to a true anatomical coordinate system, and / or, identify, by itself (or with the aid of an operator of the computing device) a marker within the 2D image that corresponds to a contact surface of the custom registration guide. In another embodiment, one or more of these operations are performed by an operator, while other operations are performed by a computer program. Thus, any of the operations and methods described herein may be performed by an operator of a computing device or the computing device itself, by hardware, software, or a combination of both hardware and software. The specific operations and considerations in operation 1606 are described in more detail in U.S. Patent No. 10,139,807, cited herein.

[0115] Using the various electronic identifiers identified on the 2D image, the computing device can create a program or computing information based on the electronic identifiers in operation 1608. A milling device (such as a computer numerical control (CNC) milling device in operation 1610) receives the computing information and uses it to manufacture a customized registration guide for joint replacement surgery. Typically, a CNC device or robotic device operates through program instructions and performs additive or subtractive processing according to the instructions. For example, the CNC converts commands into control signals for a cutting device (tool) to process the raw material blank into a customized guide. About Fig.16 In the method, the computing device generates computing information associated with the electronic identification in the 2D image and uses the computing information to create a series of commands for CNC operations. Therefore, the customized joint replacement surgery registration guide is processed by CNC according to the instructions of the milling program, which includes the electronic identification in the 2D image and the relevant information of the raw material blank. In this way, the 2D image of the joint is used to create a customized joint replacement surgery registration guide.

[0116] Through the above process, a customized registration guide can be specially designed and processed for patients undergoing joint replacement surgery. In particular, the customized registration guide can stably cooperate with the patient's bones at several points. The registration guide does not need to be made exactly the same as the patient's bone surface. Only a few identifiable feature points on the registration guide are required to achieve a close and stable fit between the registration guide and the patient's bone surface. In other words, by identifying the characteristic positions or parts of the patient's bones in the 2D image, a customized registration guide that matches the patient's anatomical structure can be created without creating a 3D model of the patient's bones. This can greatly reduce the time required to create a customized registration guide. In addition, the creation of the registration guide and the preoperative plan 1406 can be performed simultaneously based on the patient's scan imaging, because the registration guide does not involve other steps such as osteotomy fixtures, other parts of the osteotomy, and joint surface reconstruction.

[0117] Figures 17A-17ESome embodiments of custom registration guides for robot-assisted joint replacement surgery are described by way of example. Fig.17A A custom femoral registration guide 1702 for total or partial knee replacement surgery is shown, created from a 2D image of a patient's knee joint. Typically, the femoral registration guide 1702 is fixedly or otherwise mated to the patient's femur 1704 through a number of mating surfaces specifically selected and created on the patient's knee joint image, providing a stable support base for the registration guide. U.S. Patent No. 14 / 820,451 details the creation of a custom femoral registration guide 1702 and the selection of mounting locations on the femur 1704, which will be referenced and cited in its entirety herein. If explained in more detail, the reflective cursor may have one or more 1706a-1706c mounting locations on the custom femoral registration guide 1702, which are fixed by fixing pins drilled into the bone to track the movement and position of the femoral registration guide 1702. In the figure, the femoral registration guide 1702 is fixed with the reflective cursor only at three mounting locations 1706a-1706c, and the number of such mounting locations may be greater and the locations may also vary.

[0118] Fig. 17B An example of a customized tibial registration guide 1710 for total or partial knee replacement is provided. As described above, a customized tibial registration guide 1710 can be created from a 2D image of a patient's knee joint. Typically, the tibial registration guide 1710 is matched with the patient's tibia 1712 in a fixed manner or the like through a number of mating surfaces specifically selected and created on the patient's knee joint image, providing a stable support base for the registration guide. U.S. Patent No. 9,883,871 details the creation of a customized tibial registration guide 1710 and the selection of its mounting position on the tibia 1712, and the entire contents of the same will be referenced and cited herein. In addition, similar to the above-mentioned femoral registration guide 1702, a reflective cursor may have one or more 1714a-1714c mounting locations on the customized tibial registration guide 1710, which are fixed by a fixing screw drilled into the bone to track the movement and position of the tibial registration guide 1710. In the figure, the tibial registration guide 1710 has reflective cursors fixed only at three mounting locations 1714a-1714c. The number of mounting locations like this may be greater and the positions may also vary.

[0119] In a similar manner to the femoral registration guide 1702 and the tibial registration guide 1710, other custom registration guides can be created for other joints and / or patients based on the 2D scan imaging of the patient. Fig. 17C A custom acetabular registration guide 1720 for total or partial hip replacement surgery is shown. A custom registration guide for the femoral portion 1725 of a hip joint 1722 can also be created for total or partial hip replacement surgery, such as Fig.17DAlso similar to the customized registration guide described above, the registration hip joint guides 1720 and 1721 may have a plurality of mounting locations 1724a-1724b for mounting a reflective cursor to track the movement and position of the hip joint registration guides 1720 and 1721. Fig.17E A custom spine registration guide 1730 for spinal arthroplasty surgery is illustrated. Similarly, the custom spine registration guide 1730 can be created based on an image of a patient's spine 1732 and can be mounted on a number of pre-selected locations of the patient's spine vertebrae to provide a secure fit for the registration guide. Also similar to the custom registration guide described above, the spine registration guide 1730 can include a number of mounting locations for securing a reflective cursor to track the movement and position of the registration guide 1730.

[0120] Back to Fig.14 System 1400 and Fig.15 In the method 1500, with the approved surgical plan 1406 and one or more customized bone registration devices 1404, the intraoperative stage begins from step 1506. More specifically, the customized bone registration device is transported to the surgical hospital, and the surgical plan 1406 can be uploaded to a computing device or a robotic surgical assistant via a network. In some instances, a milling program for machining the bone registration device 1404 can be provided to a computing device or a robotic device. Generally, information such as the size, position and orientation, specifications, contours, structures, shapes, etc. of the bone registration device of joint replacement surgery can be provided to a computing device or a robotic device for intraoperative positioning of the patient's anatomical structure. In some cases, the surgical plan can also be uploaded to a robotic surgical assistance device in step 1508. Generally, a robotic surgical assistance device can be an independent robotic device (not connected to the surgical patient) or an attached robotic device (attached to the patient's anatomical structure in some way). Regardless of the type of robotic surgical assistance device used, the robotic device can receive the surgical plan and perform certain steps according to the surgical plan, such as osteotomy or surface reconstruction.

[0121] First, the benefits and advantages of using a patient-customized guide with a stand-alone robotic device (not attached to the surgical patient) are described. Fig. 20 The benefits and advantages gained from using an attached robotic surgical assist device will be described in detail below. Regardless of the robotic surgical device used, using 2D images to create a bone assembly 1404 can improve the efficiency and accuracy of both the preoperative and intraoperative stages of joint replacement surgery.

[0122] For independent robotic surgical assistance devices, the robotic device can determine the position and orientation of the surgical site, the position and orientation of the osteotomy plane, and surface reconstruction based on information such as the patient's position and orientation and the surgical plan. In other words, once the 3D position of the osteotomy or surface reconstruction is identified from the surgical plan and the patient's position, the robotic-assisted device can perform the osteotomy or surface reconstruction. As shown in step 1510, the computing device or the robotic-assisted device can map the position and orientation of the registration guide on the patient's bone with itself to determine the relative position and orientation with the patient. In one instance, the robotic device may include an optical locator similar to that described above. Fig.12 As shown, the optical locator 1210 may include a stereo sensor 1212 for positioning one or more cursors on the registration guide on the patient's bone. In this example, the surgeon can fix the registration guide to the patient's bone during surgery. Unlike the above-mentioned system where the cursors 1204 and 1211 are fixed to the patient's anatomical structure, the femoral registration guide may have one or more cursors installed on it, and the installation position may be similar to Fig.17A Locations 1706a-c of the femoral registration guide 1702. This approach would not require mounting a cursor on the patient's bone or other anatomical structure. Other types of registration guides may have similar mounting portions for securing a cursor.

[0123] In this example, the stereo sensor can position the cursor on the registration guide and calculate the position and orientation of the patient's bones based on the cursor position and orientation. Fig.13 Taking the system 1300 as an example, the optical locator 1308 can measure the distance between the optical locator and each optical sensor connected to the patient and provide it to the computing device 1302 or the robotic device 1304. Then, based on the received distance, the computing device 1302 or the robotic device 1304 can map the 3D spatial position and orientation of the cursor relative to the robotic device. Specifically, when the 3D spatial position of the robotic device 1304 is known, the computing device 1302 or the robotic device can determine the relative position and orientation of the patient's bone 1306 and the robotic device. More deeply, the computing device 1302 or the robotic device 1304 knows the size and shape of the customized registration device 1404, and can determine the position and orientation of the patient's bone 1306 under the guide plate (or otherwise related to the registration device), and apply it to the surgical plan received in the preoperative stage. Since the robotic device 1304 knows the precise position of the patient's bone 1306, the position and orientation of the osteotomy plane or reconstructed surface can be determined in 3D space. In this way, the customized registration guide 1404 can assist the robotic device 1304 in locating the patient's anatomy and assist the surgeon in performing the procedure.

[0124] It is worth noting that the above method and system no longer require Fig.12The registration step in the process of registration is eliminated. Unlike the detection device fixed to various positions of the patient's bones to register the femur position with the robotic device 1304, the registration guide 1404 can provide registration information to the robotic device in real time, saving surgical time and avoiding potential registration errors. In addition, since the registration information does not need to be mapped to the 3D model of the patient's anatomical structure, the step of creating a 3D model in the preoperative stage can also be omitted. The use of a customized registration device can improve the efficiency and accuracy of joint replacement surgery and reduce the potential defects of previous robot-assisted joint replacement surgery.

[0125] In another example, the robotic device 1304 may be registered with the patient's position without the optical positioning device 1308 . Fig.18 A system diagram of another embodiment of a robotic-assisted joint replacement surgery using a customized registration device is specifically shown. The system 1800 may include a robotic surgical assistance device 1304 as described above, which is used to perform osteotomy or surface reconstruction on a patient's bone 1704 during surgery. As described above, before osteotomy, the robotic device 1304 may use a customized registration guide 1702 to register the position and orientation of the patient's bone 1704. More specifically, the robotic device 1304 may match the registration guide 1702 with the patient's bone 1704. In one example, a surgeon or a visual system with object recognition software can help the robotic device 1304 to install the registration guide 1702 on the patient's bone 1704 by installing the registration guide in an initial position on the bone connected to the robotic device 210, or by installing the robot 1304 in the initial position where the registration guide is installed. For example, the robotic device 1304 may have a guide mounting end 1802, and the mounting end has a force or torque sensor 1804 and a mechanical structure that cooperates with the guide 1702. The robotic device 1304 adjusts its position and orientation so that the mechanical structure of the mating end 1802 is connected to the registration guide 1702 and is attached to or close to the patient's bone 1704. In short, any mechanical connection can be used for the cooperation between the robotic device 1304 and the registration guide 1702 to map the relative positions of the two.

[0126] Once connected, the robotic device 1304 or the surgeon can place the registration guide 1702 on the patient's bone 1704 and engage it in place. For example, according to the installation procedure, the registration guide 1702 is placed on the patient's femur, the guide is rotated in a first direction to find the appropriate position, and the guide is vertically translated to lock it in the appropriate position on the bone 1704 so that it engages with the patient's femur. Different locking actions can be developed for the various registration guides 1702 described above to lock the guide in the appropriate position of the bone. These locking steps or actions can be provided to the surgeon or programmed into the robotic device 1304 to correctly place the registration guide on the corresponding bone position of the patient.

[0127] In some cases, the robotic device 1304 is provided with a torque sensor 1804 at the mating end 1802. In order to assemble the registration guide 1702 to the patient's bone 1704, the torque sensor 1804 provides the measured force and / or torque value to the robotic device 1304 or other computing device. For example, the customized registration device 1702 and the torque sensor 1804 can be connected through a ball probe or other mechanical component, and the mechanical component transmits the force to the robotic device 1304. The robotic device 1304 mates with the registration device 1702 through the torque sensor 1804 at the mating end (end effector) 1802 and ensures that the registration device is installed in place. For example, the robotic device 1304 can be configured to move the registration guide 1702 using any 3D movement with 6 degrees of freedom. The robotic device 1304 obtains the force and / or torque value measured by the torque sensor 1804 and assembles the registration device 1702 to the patient's bone 1704. In a specific example, when the robot device 1304 assembles the registration guide plate 1702 to the bone 1704, when the torque sensor 1802 measures that the movement resistance of the guide plate 1702, the rotation torque along the first direction, and the vertical translation force reach certain values, it means that the installation is in place. Through the torque sensor 1804, the robot device 1304 can lock various registration guide plates 1702 to the patient's bone 1704.

[0128] Regardless of whether the registration device 1702 is mounted on the patient's bone 1704 before or after the connection with the robotic device 1304, and regardless of whether the registration guide is mounted on the patient's bone by the robotic device itself, the robotic device can determine the position and orientation of the patient's bone based on the position of the registration guide. For example, the robotic device 1304 can be equipped with one or more motion sensors to know the 3D position and orientation of its mating end 1802. Further, the robotic device 1304 can know the size of the registration guide 1702, so that the normal vector of the registration guide can be calculated or determined, and then the relative 3D position and orientation of the two can be calculated or determined. Therefore, the robotic device 1304 can determine the 3D position normal vector of the guide relative to it by connecting its mating end 1802 with the registration device, using the relative position with the registration guide 1702 and its inverse kinematics equation. Furthermore, the calculated 3D normal vector can be mapped to the normal vector of the osteotomy surface in the surgical plan by the robotic device 1304 or a computing device that controls the robotic device.

[0129] like Fig.18As shown in the system 1800, the robotic device 1304 is mounted or connected to the registration guide 1702 fixed to the patient's bone 1704. The position and orientation of the robotic device 1304 are mapped 1806 to the registration guide 1702, and the robotic device 1304 can obtain the relative position and orientation of the patient's bone 1704. In addition, the position and orientation of the normal vector of the registration guide 1702 can be determined by mapping 1806. In some cases, the normal vector can be provided by the approved surgical plan, or can be calculated based on one or more markers on the registration guide 1702. Since the position / orientation of the normal vector of the registration guide 1702 is determined, the normal vector of the osteotomy surface 1812 can be calculated by the preoperative surface model 1810 of the surgical plan, and the robotic device 1304 or the computing device can map 1808 the registration guide normal vector to the osteotomy surface normal vector. After the registration guide 1702 matches the normal vector of the osteotomy surface 1812 in the surgical plan, the robotic device 1304 can determine the position and orientation of the osteotomy surface. The application of the osteotomy surface position during osteotomy by the robotic device 1304 will be described in detail below.

[0130] It is appreciated that due to the use of the customized registration guide 1702, an optical locator is no longer required for surgery. Unlike the cursor on the monitoring detection device described above, the robotic device 1304 can map the position of the guide 1702 registered with the patient's bone position to the position of the robotic device 1304. Therefore, the mechanical cooperation between the registration guide 1702 and the robotic device 1304 can provide registration for the mapping process, thereby eliminating the need for an optical locator to position the cursor associated with the patient's bone 1704. By eliminating the positioning device (e.g., a computer navigation system or an imaging system), the cost of the operation is reduced. In addition, since the precise size of the registration guide 1702 is known from the milling program, the positioning accuracy of the patient's bone 1704 can be improved, which also improves the mapping accuracy of the osteotomy plane 1812 and the patient's bone in the surgical space.

[0131] Back to Fig.14 and Fig.15 During the surgical operation 1512, one or more motion sensors 1410 are mounted on the patient's anatomical structure to monitor the patient's movement during the operation and adjust the position and direction of the predetermined osteotomy surface. As described above, previous joint replacement surgeries may use a cursor mounted on or near the patient's anatomical structure. By monitoring the reflected cursor with an optical locator, the patient's movement during the operation can be measured. However, since the movement on the line connecting the locator and the cursor may not be accurately measured, and / or there may be obstacles between the two, not all movements can be monitored, resulting in inaccurate osteotomy. In another example, if Fig.19As shown, one or more inertial sensors 1902 are mounted or otherwise connected to the patient's anatomical structure 1704, and the monitored motion is wirelessly transmitted to the robotic device 1304 or the computing device 1302 to adjust the osteotomy surface position of the patient's bone 1704 in the established surgical plan. In one example, one or more fixation pins 1904 are mounted to the patient's bone 1704 (for example, bone screws are inserted into the bone). The inertial sensor 1902 connected to the bone 1704 can monitor 6-degree-of-freedom motion, including the rotation of the bone along any 3D axis. In addition, the use of the inertial sensor 1902 can eliminate the need for an optical positioner to monitor the cursor, and the monitoring accuracy is higher.

[0132] exist Fig.15 In operation 1514 of method 1500, the robotic device 1304 can perform osteotomy or surface reconstruction on the patient's bone according to the position and direction of the predetermined osteotomy surface and the surgical plan. However, through the above method 1500 and device, many inaccuracies of previous robot-assisted joint replacement surgery can be eliminated, while reducing the surgical costs of medical institutions.

[0133] In some embodiments, the robotic device 1304 may include a surgical assist device mounted on certain parts of the patient. For example, the robotic device may be attached to the patient's bones in a variety of ways, with or without the help of the registration device 1702 described above. For example, Fig. 20 The invention shows a method for installing a robotic surgical device on a patient's femur 2001 using a mechanical registration guide system. Specifically, the robot is installed as follows: first, a hole is drilled in the center of the patient's knee joint 2009 and an intramedullary rod 2003 (representing Figure 7 The plate 2008 may then be connected to a slide bar 2010 (representing the front / back line 707). The plate 2008 may be rotated around the rod 2010 to set the valgus / valgus angle and the upper / lower position of the implant. Attached to the bottom of the rod 2010 may be a vertical plate or plate 2006, which serves as the lowest reference point for the medial and posterior condyles 2004. The plate 2006 represents the medial / external rotation angle 707 in the axial plane 702 around the center of the knee joint 706. Connected to the plate 2008 on the medial or lateral side is a robotic arm 2007 of approximately 40-80 mm in length, which is perpendicular to the plate 2008. Two parallel drill holes 2005 are located at the end of the arm 2007, near the anterior medial side of the femur 2001. Two fixation pins or bone screws are passed through the two holes to mount the robot in the correct position and orientation according to the specifications of the implant. According to the robot's operating space, the positioning pin or hole for installing the robot can be located at any position of the inner or outer side of the femur. Finally, the stylus 2011 registers the anterior crest of the outer 2002 of the femur 2001 (near the inflection point), which can be raised or lowered along the rod 2010 to determine appropriate implant specifications.

[0134] Combination of the above Fig.12 An alternative approach to installing robotic equipment using computerized navigation systems is briefly described. Fig.12 , when installed, the bone landmarks are registered with the reflective cursor 1210 and the probe (with known compensation and diameter). The stereo sensor 1212 uses infrared (IR) 1202 to monitor the reflective cursor 1210 with a unique configuration and uses the compensation to calculate the position and orientation. One of the disadvantages of optical tracking technology is the need to establish an unobstructed line of sight. The process first uses a handheld tool 1208 with a cursor 1210 to register anatomical landmarks to determine the position and orientation of the knee joint 1205. For example, the center of the knee joint, the lowest point of the medial and lateral condyles, the medial and lateral sides of the femur, and the anterior cortex of the lateral ridge. In addition, the cursor 1211 is connected to the femur and the knee joint is rotated, making circular and linear motions, and a spherical contour with a specific center and a specific radius can be used to estimate the center of the hip joint. Once the position of the knee joint is determined, the corresponding implant specifications can be selected based on the height and width of the knee joint size. According to the selected implant specifications and ideal position, a fixation pin 1206 (with cursor 1204) is drilled into the medial condyle, which corresponds to the correct varus / valgus angle of the implant, and the position of the fixation pin relative to the center of the knee joint and the two posterior condyles should be within the robot's operating space, as described in detail below. Finally, the base joint 1209 of the robot with cursor 1203 can be fixed to the pin 1206. Before the robot 1201 is fixed to the pin 1206, the cursor 1203 keeps tracking the position and orientation of the robot to find the ideal implant position.

[0135] There is another technique for attaching robotic devices to the patient’s anatomy. Fig.21 is a perspective view of a patient's knee joint, with a customized registration guide 2105 placed at the end of the patient's femur 2102, the guide having guide holes 2103 for fixation pins on the medial side 2106 of the femur and guide holes 2104 for fixation pins on the distal side 2102 of the femur. The fixation pins may also be drills, pins, or screws. The customized registration guide 2105 may be created by one or more of the above techniques, such as by analyzing and processing a 2D image of the patient's joint. Typically, the customized guide 2105 has at least one guide hole for fixation pins to mount the robot in any desired anatomical position on the medial side, distal side of the femur, or near the surgical site. For example, in a lateral unicondylar arthroplasty, the robot may be mounted on the lateral side of the femur. For patellofemoral arthroplasty, the robot may be mounted on the anterior cortex of the femur. For a femoral osteotomy, the robot may be mounted on the femoral shaft near the knee joint. The same is true for the tibia.

[0136] In this technique, after opening the soft tissue around the knee joint, the patella is moved to the outside, and the femur 2101 and tibia 2107 are exposed. As described above, in preoperative planning, the surgeon can determine the desired position and specifications of the knee implant for the patient. By using the same reformatted 2D image, the preoperative planning and the design of the customized guide plate have the same anatomical coordinate system. Using this anatomical reference system, the ideal position and direction of the knee implant are translated or mapped to the customized registration guide plate 2105 in the subsequent production process. In one embodiment, a surface or 3D model can be created from a series of 2D images (CT or MRI) of the patient's knee joint (although the method does not require the creation of a 3D model). This is used for preoperative planning to determine the ideal implant specifications and position and to design a customized guide plate. Intraoperatively, the customized guide plate is installed on the patient's knee joint and cooperates with the contact points (reformatted 2D images) or contact surfaces (3D models) in the customized guide plate design. The orientation of the fixation pin holes (2103 and 2104) represents the position and orientation of the knee implant in all 6 degrees of freedom (3 rotations + 3 translations) as planned preoperatively. For example, the fixation pin hole 2103 can be set with respect to the initial compensation of the center of the femur (COF) (along the y-axis), and with respect to the orientation of the knee implant (about the x-axis and the z-axis). The fixation pin hole 2104 can be set with respect to the initial compensation of the COF (along the x-axis and the z-axis), and with respect to the orientation of the knee implant (about the x-axis and the z-axis). Using the customized guide and imaging data obtained by the above process, registration of the patient with the robot can be established in this way.

[0137] Fig. 22 2201 is a perspective view of a patient's knee joint, with the surgical robot mounted on the femur 2207 and tibia 2205 bones. Using one of the above registration methods, the robot 2201 is mounted on the inner side of the femur by two or more fixation pins 2203 and registered with the femur 2207. In summary, the fixation pins 2203 determine the position and orientation of the robot, which corresponds to the ideal implant position and orientation determined before the operation. Similarly, if the robot 2201 is mounted at the distal end of the femur, two or more fixation pin holes 2206 can establish the ideal implant position and orientation. In one embodiment, at least one robot is mounted on the bone. In another embodiment, the robot 2202 is mounted on the inner side of the tibia 2205 and fixed by two or more fixation pins 2204, which corresponds to the ideal tibial implant position. As described above, as long as the operating space of the robot 2201 is guaranteed, the robot can be installed at any position of the anatomical structure near the surgical site.

[0138] The present invention relates to methods and systems for small robotic-assisted surgical systems mounted on the patient's anatomical structure. As described above, the present invention can be applied to orthopedic surgery on any part of the patient's joint. However, for ease of understanding, this article only discusses the surgery and embodiments related to the present invention using the knee joint as an example. Moreover, any small robotic-assisted surgical system can be used in conjunction with the systems, methods, and surgeries described herein. A small robotic-assisted surgical system is now discussed that is used in conjunction with the systems and methods described herein, fixed to the patient's anatomical structure, and performs preoperative planning.

[0139] Specifically, Fig.23 It is a single-link robot with two rotational joints (θ1, θ2) or 2 degrees of freedom. In one embodiment, the robot includes two rotational joints (θ1, θ2), the first joint θ1 is on the base 2302, the second joint θ2 is on the end effector 2303, and the two joints are connected by a connecting rod 2301 (length L1). Each joint, θ1 on 2302 and θ2 on 2303, can rotate 0-360° or continuously. Different tools or instruments 2304 are connected to the end effector 2303, and within the range of 0-360° controlled by the joint 2303, these tools or instruments can be positioned at any angle θ2 in the (X, Y) plane or the trajectory in the (X, Y) space. For example, connected to the end effector 2303 is a guide 2304 which may be a saw blade or a fixing pin and is positioned in the operating space 2305 at an angle θ2 and coordinates (X, Y). The operating space of a 2-DOF single-link robot can be described by the forward and inverse kinematic equations as follows:

[0140] Inverse Kinematics:

[0141] θ1=tan -1 (Y / X)

[0142] θ2=constant

[0143] Where X and Y are the coordinates (X, Y) of the end effector in the coordinate system (X0, Y0) in millimeters.

[0144] Forward Kinematics:

[0145] X=L1*cos(θ1)

[0146] Y=L1*sin(θ2)

[0147] The joint angles of the 2-DOF robot are θ1 and θ2, in degrees, and the length from the center of the rotation joint 2302 to the center of the rotation joint 2303 is L1.

[0148] The circumference or diameter of the operating area can be defined by the connecting rod L1. In some embodiments, L1 is a fixed length that can accommodate various implant specifications (heights) with different internal geometries. The center of the base or operating space with radius L1 can be located anywhere on the inner side 2206 or outer side of the femur to accommodate different knee implant specifications and internal geometries. The operating space requirements for the design of the knee surgery robot will be described in more detail below.

[0149] Fig.24A It is a cylindrical coordinate robot with a rotary joint and a linear joint (2 degrees of freedom). The length L2 of the linear actuator 2404 is about 0 to 50 mm and can be connected to the end effector 2403. Fig.23 The system shown is similar. In one embodiment, the linear arm / actuator can be static or dynamic, which means that the control or adjustment of the length L2 can be driven by a servo motor with a universal gear 2403, or manually adjusted through a sliding arm or an arm of fixed length. In another embodiment, the linear arm 2404 can be a piston driven by air or hydraulics, a tensioning device (such as a spring connected to a fixed arm, and / or, a force / pressure sensor, or a strain gauge). The angle θ1 of the base joint 2402 is capable of 0-360° or continuous rotation. Different tools / instruments (such as power tools such as milling cutters, drills, etc.), or osteotomy guides, or instruments / sensors (such as cursors, cameras or probes, etc.) can be connected to the end effector 2405. The operating space of the 2-DOF robot can be described by the forward and inverse kinematic equations as follows:

[0150] Inverse Kinematics:

[0151] θ1=tan -1 (Y / X)

[0152]

[0153] Where X and Y are the positions of the end effector in the coordinate system (X0, Y0) in millimeters; θ1 is the angle of the base joint in degrees; L1 is the fixed length of the base joint, and L2 is the variable length of the linear arm.

[0154] Forward Kinematics:

[0155] X=(L1+L2)*cos(θ1)

[0156] Y=(L1+L2)*sin(θ1)

[0157] Where θ1 is the angle of the base joint of the linear arm with fixed length L1 and variable length L2.

[0158] The area of ​​the operating space 2406 can be defined by L1 to (L1+L2). Ideally, L2>L1, where L1 is a fixed length and L2 is a variable length to accommodate different implant specifications (heights) and internal geometries. The center of the operating space defined by the robot base or 2402 can be located anywhere on the medial, lateral, or anterior femur to accommodate different surgical techniques, different knee surgeries, knee implant specifications, and internal geometries. In one embodiment, the robot in FIG. 24 is mounted on the medial tibia (see FIG. Fig. 22 ), the tibia is osteotomized and replaced with an implant, e.g. Figure 8 Unicompartmental surgery as shown in .

[0159] Fig. 24B It is a 6-DOF robot (five rotational and six linear joints) whose spherical operating space is defined by the radius (L1+L2+L3+L4+L5+L6). Each joint 2410-2415 (θ1, θ2, θ3, θ4, θ5 and θ6) is capable of 0-360° or continuous rotation. In one embodiment, the robot has several degrees of freedom. In another embodiment, the length of each link (L1, L2, L3, L4, L5 and L6) of the robot can be fixed, variable, or any combination of fixed and variable lengths to adapt to the operating space and the internal geometry of the implant. The operating space of the 6-DOF robot can be described by Denavit-Hartenber (DH) parameters, and the DH matrix can be used to calculate the forward and inverse kinematic equations of the robot. In general, the DH method can be used regardless of how many degrees of freedom the robot has.

[0160] Fig.252501 includes two rotary joints at 2502 and 2503, which are driven by two DC / AC, brush / brushless servo motors respectively. The robot can be rectangular, square, oval or other geometric shapes to accommodate the size of the internal electromechanical and different incision sizes. The robot shell or outer box can be made of plastic, aluminum, carbon fiber or other materials to accommodate internal components. The cross-sectional view or side view of the robot in 2510 shows the internal components of the robot, such as sensors, electromechanical, electrical and power supply systems. The robot has two motors (with or without internal gears) for increasing or decreasing torque / speed, and encoders (optical / mechanical) for measuring the position, speed or acceleration of motors 2512 and 2514, respectively, and performing feedback control on the motors. The electronics 2525 include communication modules (wired / wireless), power management, motor drive electronics, microcontrollers, other electronics, and sensors (e.g., temperature and / or current sensors) connected to input and output signals to monitor the operation, safety, and status of the robot. The robot is powered by an internal rechargeable lithium battery or similar chemical battery 2516 with a voltage range of approximately 5 to 48 volts, which is removable, rechargeable, and replaceable. In one embodiment, the battery or power source is located outside the chassis. A cable or wireless transceiver is connected to the robot to power the electromechanical system. In another embodiment, the motors, gears, and sensors are mounted inside the robot, while the electronics, microcontroller, and power source are mounted outside the chassis via a wired cable or wireless transceiver.

[0161] In addition, sensors 2519, such as inertial measurement units (accelerometers, magnetometers and / or gyroscopes), temperature or other sensors, are mounted on a PC board inside the robot. Generally, the higher the voltage, the faster the speed; and the higher the current, the greater the torque. The external display module 2518 provides visual indication of intraoperative operations and is controlled by the surgeon. The bus cable 2517 provides signals to the display module. By disconnecting the bus 2517, all internal components can be removed individually from the chassis 2501. Finally, a top view of the robot 2520 provides I / O control and visual display to the surgeon. The robot's movement is controlled by one or more buttons or other input devices, such as voice commands, touch sensors, or other types of interfaces. For example, pressing button 2521 once will cause the robot to advance from position 1 to position 2 (indicated by the LED in 2525); pressing button 2522 once will cause the robot to move from position 2 to position 1, such as Fig.25In one embodiment, by pressing button 2521, the end effector of the robot moves linearly along the X-axis 2523 in increments of 0 to 1 mm, and the LEDs display the movement. Similarly, by pressing button 2522, the robot moves linearly along the Y-axis in the operating space in increments of 0 to 1 mm, and the LEDs display the movement (see FIG. Fig.23 ). In one embodiment, the LED may be an LCD or other type of touch-sensitive display (e.g., capacitive). In another embodiment, pressing the button for more than 1 second adjusts the robot's current state to 2523, 2524, 2525 in any order, and pressing the button once advances the robot one position. The entire housing / box of the robot is sterile and can be used once or repeatedly. The robot housing is sealed to prevent water from entering the internal components, while preventing a non-sterile robot that is used multiple times from infecting the patient.

[0162] Fig.26 This is a perspective view of the internal electromechanical and external appearance of a 2-DOF (1 rotation + 1 linear joint) small surgical assistance robot. Fig.25 Similarly, the robot 2601 has two revolute joints 2503 and 2502 in the bottom view. At any revolute joint, the linear actuator 2604 can be connected to the motor 2605 and the universal gear 2604, and the revolute joint can drive the variable linear actuator 2603 using a 90-degree gearbox. The linear actuator 2603 is connected to the gear 2604 and can be extended and retracted in the operating space, and its end is connected to the end effector 2602. Next, the side view 2610 and Fig.25 The linear actuator 2604 is similar to the linear actuator 2604 except that the shaft 2611 of the DC servo motor 2613 is directly connected to the internal gear 2604 of the linear actuator. The position of the linear actuator is controlled by the DC servo 2613 with an encoder and gears. For example, the circumference of one revolution of the DC servo motor can be equal to the length of the arm 2603. The universal gear 2604 and the linear arm 2604 can be separated from the motor shaft 2611. In one embodiment, Fig.15 Robots and Fig.26 The robot 2620 is similar to the robot 2620, except that the end effector is connected to a mechanical actuator. Finally, the top view of the robot 2620 has one or more buttons 2621 and 2622, and a display 2625 (for monitoring the real-time status of the movement: along the X-axis 2623, the implant position, and the linear movement along the Y-axis 2624). In one embodiment, the display 2625 is an LCD that can be programmed to display different implant images, text instructions, or real-time data related to the surgery.

[0163] Fig. 27 is on the robot base (see Fig.25 and 26) is a perspective view of a fixture mounted on a . Starting from the top view, the fixture includes a plate 2701 and two vertical pins 2702 that match the distal bore holes 1206. On the other side of the plate is a locking mechanism 2703 connected thereto. A rod 2704 is inserted into a hole on the side of the locking mechanism and fixed to the plate 2701. The rod 2704 can be square, round, or other shapes and can slide along the y-axis to adjust the position. A hinge 2705 is located at the end of the slide 2704 and can rotate freely about the z-axis or can be locked by the locking mechanism. In one embodiment, the hinge 2705 includes a sensor for measuring the rotation angle of the hinge. In another embodiment, the hinge is a DC servo motor, an encoder, or a protractor fixed at a certain angle. In the front view, the locking mechanism 2703 includes a hexagonal screw 2712 that fixes the rod 2704 to the fixture. In addition, the locking mechanism allows the rod 2704 to rotate about the x-axis. In one embodiment, the locking mechanism 2703 includes a sensor for measuring the rotation angle. Finally, hinge 2705 allows the fixture to rotate about the z-axis. The locking mechanism will Fig.28 More specifically, Fig.28 2801 is a perspective view of a locking mechanism 2801 that secures the robot to the patient's femur via a fixing plate 2810. The locking mechanism may be a cylinder 2802 having a through hole 2803. A screw 2805 is inserted into the cylinder 2802, and the two are approximately equal in length. The screw has a square or round sleeve 2812 in the middle, and the sleeve diameter or cross-section may be the same size as the through hole 2803, or may be larger or smaller. The screw head 2806 is tightened to be flush with the cylinder 2814. When the screw is tightened, the sleeve 2812 moves in the direction of the screw, and the rod 2804 is clamped between the sleeve 2812 and the through hole 2811 and is locked. In addition, the screw 2805 may be screwed into the clamp 2810 to prevent the rod from rotating. In one embodiment, Fig.28 The locking mechanism without plate 2810 can be with arm 2007 (see Fig. 20 ) has the same structure, while arm 2006 (see Fig. 20 ) is arm 2804 (see Fig.28 ). Fig. 22 The two drill bits shown at 2203 and 2204 secure the plate to the bone, and the locking mechanism can be part of the plate.

[0164] The present invention relates to methods and systems for small robotic-assisted surgical systems mounted on the patient's anatomical structure. To facilitate the following discussion, different robot configurations from 2 degrees of freedom to 6 degrees of freedom are briefly described, including mechanical clamps, force / torque sensors, and visual indicators (such as protractors, etc.). As mentioned above, the present invention can be applied to orthopedic surgery on any part of the patient's joint. However, for ease of understanding, this article only takes the knee joint as an example to discuss surgeries and embodiments related to the present invention.

[0165] Fig.29A It is a 2-DOF robot 2901 (see Fig.26 ) perspective view, 3-DOF fixture (see Fig. 27 ) is fixed to the distal end of the femur, and the 2-DOF robot 2901 is assembled on the fixture through its base. The 5 degrees of freedom of the robotic device include: a rotational joint 2902, a linear actuator 2905, and 3 degrees of freedom on the fixture (a rotational hinge 2904, a slide bar 2906, and a rotational locking mechanism 2907). In one embodiment, the hinge 2904 is fixed at 90° perpendicular to the slide bar 2906. In another embodiment, the locking mechanism 2907 is fixed at 0°. The robot 2901 can be separated from the structure 2902 and the structure 2903 and reconfigured for different surgeries or applications. Similarly, Fig.29B is a perspective view of the robot, 2-DOF fixture (see Fig. 27 , without hinge) fixed to the distal end of the femur, 2-DOF robot 2901 (see Fig.26 , with end effector 2911) assembled on the fixture. Fig.25 The 4 degrees of freedom of the robot include: two rotational joints 2911, 2912, and 2 degrees of freedom of the fixture (with a rotational locking mechanism 2913 and a slide bar 2914). After the distal femoral osteotomy, the plate 2915 will be fixed to the bone. Similarly, the robot 2910 can be separated from 2911, 2912 and can be reconfigured for different surgeries or applications.

[0166] Fig.30 It is a perspective view of a 2-DOF robot 3001. The robot is fixed to the patient's anatomy 3009, and its attachment has 4 degrees of freedom and is connected to the end effector. Fig.25 The 6-DOF robot device includes two rotary joints 3002 and 3003 , a rotary hinge 3004 , a linear actuator 3005 , a locking mechanism 3006 and a sliding rod 3007 . Fig.30 The robotic device in allows for flexibility of up to 6 degrees of freedom. In one embodiment, hinge 3004 is fixed at a right angle (90°), making it a 5 degree of freedom robot. In another embodiment, locking mechanism 3006 is fixed (e.g., at 0°), making it a 5 degree of freedom robot. In another embodiment, both hinge 3004 and locking mechanism 3006 are fixed, making it a 4 degree of freedom robot. In another embodiment, another 2 degree of freedom robot similar to 3001 is connected perpendicularly to hinge 3004 with one of the rotational joints, making it a 4 degree of freedom robot. Of course, different accessories, sensors, tools, or other similar or different robots can be connected to the robot. Fig.25 The attachment can be any degree of freedom, any form of linear actuator, another robot 3001, a simple osteotomy guide or drill guide, a more complex mechanical fixture or robotic gripper, etc.

[0167] The present invention relates to methods and systems for miniaturized robotic assisted surgery systems mounted on the patient's anatomy. To facilitate the following discussion, the robot calibration and the different positions of the robot for osteotomy or milling are briefly described. As mentioned above, the present invention can be applied to orthopedic surgery on any part of the patient's joint. However, for ease of understanding, this article only uses the knee joint as an example to discuss the surgery and embodiments related to the present invention.

[0168] Fig.31A 3101, showing five different robot arm configurations matching five internal geometries of the femoral component 3102 within the robot operating space 3109. Starting from position 1, the coordinates (X, Y) of position 3103 are defined as the distal line 604 (see Figure 6 ) and the robot operation space 3109. Use Fig.23 The inverse kinematics equations described in can be used to calculate the joint angle θ1 of link 1 at 3108. The angle θ2 of the osteotomy guide is determined based on the internal geometry of 604. Similarly, the end effector positions 3104-3107 can be calculated using Fig.13 The inverse kinematics equations described in and the corresponding angles of the internal geometry of the knee implant 3102 are calculated. For different implant brands and specifications, the position (X, Y) of the end effector is different and can be stored in the robot's memory or transmitted to the robot before surgery. In one embodiment, a lookup table of different implant specifications and brands is stored in the robot's non-volatile memory. When the surgeon approves the surgical plan containing the ideal implant position, specifications, and brand, the robot's robotic arm and osteotomy guide will be automatically configured based on the internal geometry of each implant. In addition, the surgeon can use buttons 2531 and 2522 to adjust the osteotomy guide position based on the X and Y positions (see Fig.25 ). Using the above inverse kinematics equations for the 2-DOF robot, the corresponding angles of revolute joints 1 and 2 can be calculated. In addition, the operating space 3109 also defines the length of the robot link L1 in 2301. Because the base joint position can be adjusted according to each patient's anatomy and surgical procedure, in theory, the same robot 3101 should be able to accommodate many implant brands and specifications.

[0169] Fig.31Bis an illustration of a 2DOF robot 3102 similar to 3101 showing four different robot arm configurations adapted to four internal geometries of a femoral component 3120 within the robot's operating volume 3122. In this figure, the base position 3121 of the 2DOF robot 3102 is moved along the x-axis toward the lower end of the femur. By doing so, the diameter of the robot's operating volume 3122 can be reduced and still use the same 2DOF robot to accommodate end effector positions and angles 3123-3126. As described above, the robot's operating volume is determined by the length L2 of the robot (see Fig.23 ) definition. In addition, the angle θ2 of the osteotomy guide has two possible results: θ2 and θ2±180°. This will enable the micro-surgical robot installed on the bone to perform minimally invasive surgery and adapt to more implant brands and specifications. In one embodiment, the design of the robot can be optimized for each implant brand and specification. In another embodiment, Fig.25 The rotary joints of the robot will only need to rotate 0-180°, thus reducing the cost of the robot and simplifying the design.

[0170] and Fig.26 similar, Fig.31C is an illustration of a 2-DOF robot (one rotational and one linear joint) showing a unicompartmental implant 3145 and the robot's operating space between 3140 and 3141 adapted to the internal continuous geometry of the unicompartmental femoral component 3145. In this figure, the base position 3142 of the 2-DOF robot base 3142 is determined based on the shape of the implant. In one embodiment, the robot's operating space is fixed, but the base position 3142 is repositioned to accommodate different implant internal geometries and specifications. The base joint 3144 rotates clockwise or counterclockwise with the linear actuator 3150, moving along contours 3145 and 3146. The end effector (XY) coordinate position 3143 of the robot also moves according to the continuous contour and can be described by an n-degree polynomial or a lookup table with a series of XY coordinate points. For example, using the inverse kinematics equations, the base joint angles, linear actuator positions 3143, 3149, 3148, and 3147 can be calculated to follow the end effector position. In addition, the surgeon can Fig.26 ) to adjust the position of the end effector in 1mm increments. For example, by adding compensation to the implant profile, the surgeon can remove more bone in the X or Y direction.

[0171] Fig.32Flow chart of calibration, initialization and positioning of the robot manipulator in the correct orientation to match the internal geometry of the prosthesis. Starting from calibration at 3201, the robot's rotational joints θ1 and θ2 are adjusted by adding or subtracting the angle or implant compensation (K1 and K2) of each joint, with 0° defined by the end effector position (L1,0) of Figure 31. Sensors (such as high-resolution encoders) can accurately measure the angular position of the end effector, and the accuracy verification and calibration of the robot before surgery are completed with fixtures and sensors. The compensation values ​​are then stored in the robot's non-volatile memory. In this process, initialization operation 3202 confirms that the robot has been properly mounted on the bone and no angular changes have occurred before osteotomy or drilling in the bone. In operation 3203, the robot moves to position 1 involving: the manipulator angle A1 (the corresponding value of the lookup table of the implant's internal geometry + calibration compensation K1 + any X or Y adjustment value Δ1 made by the surgeon) and the osteotomy guide angle A2 (the corresponding value of the lookup table of the implant's internal geometry + calibration compensation K2 + any X or Y adjustment value Δ2 made by the surgeon). Similarly, in operations 3204, 3205, 3206, and 3207, for each position reached by the robot, there are angles corresponding to link 1 and the osteotomy plate + calibration compensation for each rotational joint + (X, Y) adjustments determined by the surgeon.

[0172] exist Figure 33-37 , a perspective view of the robotic arm configuration is shown, with the arm matching the internal geometry of the femoral component in all five positions. Fig.33 ), customize the registration guide (see Fig. 22 ) determines the positions of two fixing pins 3303 and 3304, which mount the single-link robot with two rotating joints 3305 on the medial condyle. The oscillating saw blade is inserted into the osteotomy guide 3308 to perform osteotomy along the Y axis to shape the distal end of the femur 3306. By recalculating the end effector position (X1, Y1) at the intersection of the osteotomy line 3308 and the robot operating space (see Figure 31), linear adjustments can be made along the X axis while maintaining the osteotomy angle. Osteotomy is performed at the posterior part of the femur 3401 (see Fig.34 ), customize the registration guide (see Fig. 22 ) determines the location of two fixation pins 3404 (which can be any suitable location on the femur) that mount the robot to the bone. The oscillating saw blade is inserted into the osteotomy guide and the osteotomy is performed along the X-axis to shape the posterior femur 3405. By recalculating the end effector position (X2, Y2) at the intersection of the osteotomy line 3403 and the robot operating space (see Figure 31), linear adjustments can be made along the Y-axis while maintaining the osteotomy angle. The osteotomy is performed at the anterior portion of the femur 3501 (see Fig.35 ), customize the registration guide (see Fig. 22) determines the position of two fixation pins 3502 that mount the robot to the bone. The oscillating saw blade is inserted into the osteotomy guide and the osteotomy is performed along the XY axis to shape the anterior femur 3505. By recalculating the end effector position (X3, Y3) at the intersection of the osteotomy line 3504 and the robot operating space (see Figure 31), linear adjustments can be made along the XY axis while maintaining the osteotomy angle. In the anterior bevel osteotomy of the femur 3601 (see 36), the registration guide (see Fig. 22 ) determines the position of two fixation pins 3602 that mount the robot to the bone. The oscillating saw blade is inserted into the osteotomy guide and the osteotomy is performed along the XY axis to shape the anterior femoral bevel 3505. By recalculating the end effector position (X4, Y4) at the intersection of the osteotomy line 3504 and the robot operating space (see Figure 31), linear adjustments can be made along the XY axis while maintaining the osteotomy angle. Finally, in the posterior bevel osteotomy of the femur 3701 (see 37), the registration guide (see Fig. 22 ) determines the position of two fixation pins 3702 that mount the robot to the bone. The oscillating saw blade is inserted into the osteotomy guide to cut along the XY axis to shape the posterior femoral bevel 3705. By recalculating the end effector position (X4, Y4) at the intersection of the osteotomy line 3704 and the robot operating space (see Figure 31), linear adjustments can be made along the XY axis while maintaining the osteotomy angle.

[0173] Fig.38 is a perspective view of a robotic manipulator with a revolute joint 3803 and a variable linear actuator 3804 that can move along a path of internal geometry of a femoral unicompartmental component 3808 that reconstructs the bone surface. Fig. 22 ) determines the position 3802 of the square fixing pins (which can be 1 or several), which mount the 2-DOF robot to the medial condyle of the femur 3801, and the mounting position should make the robot's operating space compatible with the implant. The end effector 3806 milling cutter 3806 is connected to the motor 3809, and the milling cutter moves along the internal geometry 3807-3808 of the implant. The position (X, Y) of the end effector can be used to calculate the inverse kinematics equation of the robot (see Figure 24). The forward kinematics equation can be used to calculate the position of the end effector relative to the XY axis. In order to ensure the accuracy of the bone resection, the diameter of the milling cutter is taken into account when calculating the position of the end effector.

[0174] The present invention relates to methods and systems for miniaturized robotic-assisted surgery systems mounted on patient anatomy. To facilitate the following discussion, the balancing of static and dynamic soft tissue gaps during surgery is briefly described. As described above, the present invention can be applied to orthopedic surgery on any part of a patient's joint. However, for ease of understanding, this article only uses the knee joint as an example to discuss surgeries and embodiments related to the present invention.

[0175] Fig.39 Illustration: Example of soft tissue balancing of the knee extension gap while tensioning the ligaments and correcting varus / valgus angles (if needed) using the 5DOF robot 3901. To achieve ligament balance in extension, the bone gap created after osteotomy of the distal femur and proximal tibia should be rectangular to match the internal geometry and thickness of the corresponding distal femur and proximal tibia implants. When the knee is loaded or weighted during standing, if the gap is not symmetrical, the knee will be unbalanced, resulting in the medial collateral ligament MCL and lateral collateral ligament LCL being either loose or tight (depending on which side of the ligament is longer and shorter). Two rectangular clamps are mounted on the distal femur 3902 and proximal tibia 3903. Fig. 27 A clamp 3909 is described that is mounted on the distal end of the femur. The plate 3906 pressed against the proximal end of the tibia can be a rectangular osteotomy guide or spacer. To measure the extension gap and balance the ligaments, the knee joint is fully extended while a linear actuator or piston 3908 holds the ligaments taut with a certain force. After the ligaments are tensioned, the hinge 3907 can be rotated. If the gap is symmetrical, the hinge 3907 will be at an angle of approximately 90° to the (X, Y) axis. Any asymmetric gap or angle 3904 can be monitored or measured with a sensor or protractor to determine the exact angle. In one embodiment, an asymmetric extension gap is required to correct any deformation in the alignment of the entire leg. To correct the asymmetric gap, a corresponding varus / valgus 3905 osteotomy is performed on the tibia to balance the gap.

[0176] Fig.40 Example: A 5-DOF robot 4001 is used to determine the tension (tension) 4005 of the ligaments during extension, balance the joint gap and soft tissue ligaments. The extension gap of the distal femur 4002 and the proximal tibia 4003 is balanced on both the medial and lateral sides 4004. In one embodiment, a linear actuator, spring piston or linear position sensor 4005 measures the gap distance in millimeters. If the gap is not sufficient to accommodate the thickness of the prosthesis (metal and plastic), a parallel osteotomy is performed again on the distal femur 4002 or the proximal tibia 4003. In one embodiment, the symmetry of the gap is not considered to balance the soft tissue and accommodate different implant designs. In another embodiment, the soft tissue or gap is balanced by the ideal ligament tension or stability of the medial and lateral sides of the knee joint.

[0177] Fig.41Example: Using a 5-DOF robot to determine the tension (tension) of ligaments and the angle of rotation during bending, balancing soft tissues (knee joint gap). Fig.39 Similarly, the tibia 4103 is bent approximately 90 degrees relative to the femur 4102. In one embodiment, the goal is to create symmetrical gaps on the medial and lateral posterior condyles. In another embodiment, the goal is to create an asymmetrical gap by tension of the medial collateral ligament MCL or the lateral collateral ligament LCL or rotational stability of the knee joint. In another embodiment, the medial and lateral posterior condyles are tensioned with struts instead of thin plates. The clamp 3909 is mounted on the distal femur 4106, and a linear actuator or spring piston 4107 pushes the osteotomy guide or separator 3906 toward the proximal tibia. The joint 3907 is fixed at 90°, the locking mechanism 4105 is released, and the knee joint can rotate (internal rotation / external rotation) when force is applied to tighten the ligaments. In one embodiment, the hinge 3907 is released, the rod 4108 of the locking mechanism 4105 is fixed at 0 degrees, and the knee joint can rotate under tension. The locking mechanism 4105 or hinge 3907 has a protractor with a mark to measure the rotation angle. In one embodiment, the hinge or locking mechanism has a sensor for measuring the rotation angle. The corresponding angle of 4104 can then be used to correct the varus / valgus angle of the posterior condyles of the tibia or femur to create an ideal soft tissue balance or knee flexion gap.

[0178] Fig.42A Example: A 5-DOF robot is used to determine the tension (tension) of the ligaments during flexion and balance the knee joint. The flexion gap of the distal femur 4202 and the proximal tibia 4203 is balanced on both the medial and lateral sides 4204. In one embodiment, a linear actuator, spring piston, or linear position sensor 4205 measures the gap distance in millimeters. If the gap is not sufficient to accommodate the thickness of the prosthesis, a parallel osteotomy is performed again at the distal femur 4202 or the proximal tibia 4203. In one embodiment, the symmetry of the gap is not considered to balance the soft tissue and accommodate different implant designs. In another embodiment, the soft tissue or gap is balanced by ideal ligament tension or stability of the knee joint.

[0179] Figures 42B-42C Another embodiment of using a 3-DOF robot 4201 and a mechanical scissor jack 4220 to balance the knee joint flexion gap. Fig.41As described, the linear actuator or spring piston 4107 is replaced by a simple rod / arm 4224 connected to the locking mechanism 4105. The scissor jack device 4220 consists of a central screw 4226 with opposite threads and a 4-bar rotary hinge 4221 connected to the end effector joint of the 2-DOF robot. Attached to the bottom of 4221 is a metal plate 4227 that is approximately the same width and height as the tibia 4203 in order to evenly distribute the force over the entire surface of the proximal tibia. When the end effector of the 2-DOF robot 4201 rotates clockwise or counterclockwise, the 4-bar link 4221 can be retracted or extended (see Fig.42C ), thereby raising or lowering the metal plate 4227. As described above, the goal of knee gap balancing is to create a rectangular flexion gap. This is accomplished when the rod / arm 4225 is approximately parallel to the plate 4227 and the proximal tibial cut surface 4228. The surgeon can manually rotate the tibia 4203 in the varus / valgus direction to determine if the tension of the medial collateral ligament MCL and the lateral collateral ligament LCL is correct. The height or spacing of the plates 4223 can be adjusted by a 2-DOF robot until the desired tension is achieved.

[0180] Fig.42D Another embodiment is to use two 2-DOF robots 4240 to balance the knee flexion gap. Fig.26 The unicondylar 2DOF robot described in is similar to that described in except for the portion of the display 2620. The display 4240 includes an arrow 4241 that points in the direction of the linear actuator 2603, which uses two or more spikes 4243 to push a metal plate 4242 connected to the proximal end of the tibia 4203. When force is applied through the robot's linear actuator, the spikes prevent the tibial plate from sliding. In addition, the display can show force and / or torque values ​​within a certain range indicated by an LED 4246 or displayed on an LCD. At the end of the linear actuator is a spherical instrument connected to the end effector 2602. The shape of the ball allows the 2DOF robot to rotate about its respective base joints, which are connected by plates 4243 (see Fig. 27 ) is connected to the distal end of the femur 4206. The 2-DOF robots 4240 can operate independently, coordinate with each other through wired or wireless communication, or communicate bidirectionally with a computer device.

[0181] Fig.42E It is a 2-DOF robot 4240 (see Fig.42C) side view. As described above, the base rotary joint 2605 of the robot 4240 is connected to the plate 4243 and is fixed in place by one or more pins 4262 embedded in the cancellous bone of the femur 4206. Similarly, the linear actuator of the robot 4240 is connected to the rotary joint 2610, and the actuator includes a 90 degree gear box 2640 and a linear drive arm 2603, which pushes downward on the base plate 4242 connected to the proximal end of the tibia 4203 through one or more spikes 4243. In another embodiment, for stability, the spherical instrument connected to the end effector can be a foot, a slider, or a thin plate. In another embodiment, the spherical instrument is a force sensor that measures the tension of the medial collateral ligament MCL4241.

[0182] As mentioned above, the goal of knee gap balancing is to achieve a rectangular flexion gap. In many cases, it is desirable to have different ligament tensions in the medial and lateral compartments to simulate the human knee, or the design of the prosthesis requires an asymmetric flexion gap. In addition, the medial collateral ligament MCL 105 and lateral collateral ligament LCL 103 tensions are different in male and female knees, so different ligament tensions need to be established for each patient and implant design. For ease of demonstration, Fig.42F The equilibrium state is shown with both medial and lateral ligament tension at 60 Newtons, as indicated by the LED displays 4281 and 4282. NOTE: The desired tension (tension) can be pre-programmed into each individual robot 4240 prior to surgery or wirelessly transmitted to the robot during surgery. Additionally, the knee compartments (medial and lateral) are balanced when the torque measured at each robot's base revolute joint is either 0 Newton meters or a desired torque value, and the linear actuators (2602 and 2603, respectively) of each robot 4240 are approximately 90 degrees relative to the tibial baseplate 4242. For asymmetric flexion gaps, the ligament tension for each compartment is available because each 2-DOF robot can independently drive and rotate about the base. Once the desired tension (force and / or torque) is achieved, the position (in degrees) of the revolute base joints is measured by encoders attached to the individual motors. The difference in base joint angles for the medial and lateral robots can then be used to adjust any robot that uses an osteotomy guide (see Figures 29A-29B , 30) or IR / ER in traditional four-in-one osteotomy blocks.

[0183] Fig.43 4301 is a perspective view of a femur, with a single axis of rotation 4303 defined by the centers of rotation of the medial condyle, lateral condyle (internal and lateral condyles overlap by about 0° to 30°, collectively referred to as 4302), and patellar groove 4305. Figure 39-4 2, the soft tissue ligament gap is balanced around 0° (extension) and 90° (flexion). In order to measure the ligament tension during the movement from 0° to 90°, a single axis was defined so that the robot (see Fig.23and Figure 24) can measure ligament tension using force sensors and transmit the measurements to a computer. The collected sensor data can be used to determine the normal motion of the patient's knee by comparing it with preoperative simulations, predict clinical outcomes using predictive analysis of postoperative data, or compare the performance of implants of different brands or specifications.

[0184] The present invention relates to methods and systems for small robotic assisted surgery systems mounted on the patient's anatomical structure. To facilitate the following discussion, a computer system for real-time data and communication in an operating room is briefly described. As mentioned above, the present invention can be applied to orthopedic surgery on any part of a patient's joint. However, for ease of understanding, this article only uses the knee joint as an example to discuss surgeries and embodiments related to the present invention.

[0185] Fig.44 is a perspective view of a robotic-assisted surgery system in an operating room. As described in detail above, a robotic device 4401 can be mounted on a femur 4404 using one of the registration methods. In one embodiment, the surgeon approves the surgical plan using preoperative imaging prior to surgery and then finalizes the implant brand, specifications, and location. In another embodiment, the implant brand, specifications, and location are determined during surgery. A transceiver 4405 connected to a computer 4407 transmits data to the robotic device via an interface 4406, which can be configured to match the implant specifications and internal geometry. In one embodiment, the implant specifications and brand are determined preoperatively, and the implant data is downloaded to the robot via a USB cable. During this process, the computer system 4407 tracks the surgical process in real time and displays sensor data or other key information related to the robot, such as battery life, temperature, current, torque, or any error messages, on a computer monitor 4408. In addition, as with an LCD or LED display (see Fig.25 and 26 ), commands can be sent directly to the robot 4401 via wireless or wired communication. In another embodiment, the final surgical plan is downloaded to the robot via the Internet only before the operation. The computer system 4407, monitor 4408 and transceiver 4405 are not required and are only used to provide additional real-time data. In addition, the wireless transceiver 4405 can communicate with other surgical devices or robotic devices in the form of collaboration or remote control of another device through the electrical interface 4406 connected to the computer 4407. For example, the oscillating saw 4402 is started when the oscillating saw is in the correct position and orientation.

[0186] Back to Fig.14The system 1400 in the present invention may perform some postoperative actions based on the results or data generated by the surgery. For example, a surgical results data set 1412 may be created based on information obtained from the robotic device and, in some cases, surgeon and patient feedback. Such information may be provided to a machine learning / data analysis system 1414. The machine learning system 1414 may receive several such surgical results data sets, execute one or more data analysis algorithms on the data sets, and calculate the success / failure variables of any surgery or device of the system 1400 and method 1500. In some cases, the analysis system 1414 may provide one or more recommendations 1416 at the preoperative planning 1406 stage or the patient imaging 1402 stage to improve the clinical outcomes of future joint replacement surgeries using customized registration guides.

[0187] Through the system and process described herein, a registration guide can be used to perform faster, more economical and more accurate robot-assisted joint replacement surgery. Specifically, a customized registration guide can be created from several 2D images of the patient's anatomical structure. The registration guide may include one or more mating surfaces that match a specific position on the patient's damaged joint bone. Further, because the creation of the registration guide is based on patient scans or images and does not involve osteotomy planes or surface reconstruction information, the creation of the registration guide can precede the approval of the surgical plan. During the joint replacement surgery, the registration guide can be assembled to the patient's bone by a surgeon or a robotic device, and the 3D spatial position of the registration guide can be obtained and provided to the robotic device. Therefore, the robotic device can determine the position of the patient's anatomical structure without the need for a registration process. The registration process requires a probe or surgeon to locate a specific position on the patient's bone to provide the patient's position and direction to the robotic device. In contrast, the registration device can be connected to the robotic device, and since the size of the registration device is known, the position and direction of the patient's anatomical structure can be inferred. Then, the patient's anatomical structure position can be mapped to the surgical plan, and osteotomy and / or surface reconstruction can be performed by the robotic device.

[0188] By means of the registration device, optical positioners may no longer be used in joint replacement surgery, thereby reducing surgical costs for patients and medical institutions. The registration device may also provide more accurate registration for surgery than before. In addition, one or more motion sensors may be mounted or otherwise associated with the patient's anatomical structure to wirelessly transmit the patient's movement to the robotic device to adjust the position and direction of a given osteotomy plane. Using motion sensors, such as one or more inertial sensors, the patient's movement may be monitored more accurately than optical sensors, thereby further improving the effectiveness of joint replacement surgery. Registration guides and inertial sensors may be used for any type of joint replacement surgery, including knee, hip, shoulder, spine, and other surgeries. In some cases, a virtual reality system may be incorporated into the system to assist the surgeon in performing one or more steps of a joint replacement surgery. These and all other joint replacement surgeries may benefit from the systems and methods described herein.

[0189] Fig.45 As an example, a block diagram is used to illustrate a computing device or computer system 4500 that can be used to implement the above network component embodiments. For example, the computing system 4500 (see Fig.45 ) may be the robotic device described above. The computer system includes one or more processors 4502-4506. The processors 4502-4506 may include one or more embedded caches and a bus controller or bus interface unit to direct the interaction with the processor bus 4512. The processor bus 4512, also known as the host bus or front-end bus, can be used to couple the processors 4502-4506 with the system interface 4514. The system interface 4514 can be connected to the processor bus 4512 to connect other components of the system 4500 to the processor bus 4512. For example, the system interface 4514 may include a memory controller 4514 to connect the main memory 4516 to the processor bus 4512. The main memory 4516 typically includes one or more memory cards and control circuits (not shown). The system interface 4514 may also include an input / output (I / O) interface 4520 to connect one or more I / O bridges or I / O devices to the processor bus 4512. As shown, one or several I / O controllers and / or I / O devices may be connected to I / O bus 4526 , such as I / O controller 4528 and I / O device 4530 .

[0190] The input / output devices 4530 may also include an input device (not shown), such as an alphanumeric input device with alphanumeric and other keys for communicating information and / or command selections to the processors 4502-4506. Another type of user input device includes a cursor control, such as a mouse, trackball, or cursor direction keys, for communicating direction information and command selections to the processors 4502-4506 and for controlling movement of a cursor on a display device.

[0191] The system 4500 may include a dynamic storage device called main memory 4516, or a random access memory (RAM) or other computer readable device coupled to the processor bus 4512 for storing information and instructions to be executed by the processors 4502-4506. The main memory 4516 may also be used to store temporary variables or other intermediate information during the execution of instructions by the processors 4502-4506. The system 4500 may include a read-only memory (ROM) and / or other static storage device coupled to the processor bus 4512 for storing static information and instructions for the processors 4502-4506. Fig.45 The system described in is only one possible example of a computer system that may employ or be configured according to various aspects of the present invention.

[0192] According to one embodiment, the above techniques may be performed by computer system 4500 by processor 4504 executing sequences of instructions in main memory 4516. Main memory 4516 may read these instructions from another machine-readable medium (e.g., a storage device). Executing the sequence of instructions contained in main memory 4516 causes processors 4502-4506 to perform the processing steps described herein. In alternative embodiments, circuits may be used in place of or in combination with software instructions. Thus, embodiments of the present invention may include components of hardware and software.

[0193] Machine-readable media include any mechanical device for storing or transmitting information in a machine (e.g., computer) readable form (e.g., software, processing application). Such media may take the form of, but not limited to, non-volatile media and volatile media, and may include removable data storage media, non-removable data storage media, and / or external storage devices provided with such computer program products through a wired or wireless network architecture, including one or more database management products, web server products, application surgery server products, and / or other additional software components. Removable data storage media may be a compact disk read-only memory (CD-ROM), a digital versatile disk read-only memory (DVD-ROM), a magneto-optical disk, a flash drive, etc. Non-removable data storage media may be a built-in hard disk, an SSD, etc. One or more memory devices 606 may include volatile memory (e.g., dynamic random access memory (DRAM), static random access memory (SRAM, etc.) and / or non-volatile memory (e.g., read-only memory (ROM), flash memory, etc.).

[0194] A computer program product may be stored in main memory 4516 (which may be referred to as a machine-readable medium). The computer program product includes a mechanical device that performs systems and methods according to the techniques described herein. A machine-readable medium may include any tangible, non-transitory medium that is capable of storing or encoding instructions for a mechanical device to perform operations to perform any one or more operations of the present invention; or capable of storing or encoding data structures and / or modules for use with or related to these instructions. A machine-readable medium may include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more executable instructions or data structures.

[0195] Embodiments of the present invention include various steps described in this specification. These steps may be performed by hardware components or may be embodied in machine-executable instructions that may be used to perform these steps on a general-purpose or special-purpose processor programmed with these instructions. Alternatively, these steps may be performed by a combination of hardware, software, and / or firmware.

[0196] Various modifications and additions may be made to the described exemplary embodiments without departing from the scope of the invention. For example, although the above-described embodiments relate to specific features, the scope of the invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Therefore, the scope of the invention is intended to include all such substitutions, modifications and variations and all equivalents thereof.

Claims

1. A system for robot-assisted surgery using a custom bone registration guide, characterized in that: It includes a customized registration guide (1702), on which a plurality of mating surfaces are arranged, and the plurality of mating surfaces are fitted with the damaged bone. The customized registration guide (1702) is fitted with the patient's femur by fixing or other means. The customized registration guide (1702) is provided with one or more mounting parts, and the mounting parts are used for mounting and fixing a reflective cursor, and the reflective cursor is used to track the movement and position of the customized registration guide (1702).

2. The system for robot-assisted surgery using a customized bone registration guide according to claim 1, characterized in that: The mating surface of the custom registration guide (1702) is created from a 2D image of the patient's knee joint.

3. A method for manufacturing a robot-assisted surgery system using a customized bone registration guide, characterized in that: The following steps are involved: Step S1: Obtain a 2D scan image of the patient through CT, MRI or other imaging equipment; Step S2: downloading the 2D image to a computer for processing; Step S3: Processing the 2D image and electronically marking the registered device on the patient image; Step S4: Create a machining program from the processed 2D image; Step S5: Processing the customized registration guide plate using a machining program or the like.

4. The method for manufacturing a robot-assisted surgery system using a customized bone registration guide according to claim 3, characterized in that: In step S2, the computer receives images from the imaging device via network transmission or any other form of electronic communication. After the 2D image is received, it can be stored in a computer-readable medium or cloud storage for further processing by the computing device.

5. The method for manufacturing a robot-assisted surgery system using a customized bone registration guide according to claim 3, characterized in that: In step S3, the 2D image of the joint is reformatted, the image of the machine-defined coordinate system is converted into an image that approximates the real anatomical coordinate system, and / or one or more landmarks on the patient's joint that match the contact points and contact surfaces of the customized registration guide are identified.

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