Surgical apparatus controllable by surgical robotic system

Abstract

A tissue removal assembly is provided, comprising: a first cutting member having a plurality of rotatable blades; the present invention relates to a cutting device comprising a first cutting member, a second cutting member, one or more support elements slidably or fixedly coupled to the second cutting member, where the one or more support elements comprise an annular support element inserted through an inner portion of the second cutting member; and one or more extendable elements slidably or fixedly coupled to the second cutting member wherein the one or more support elements and the one or more extendable elements are extendable and collapsible, and wherein the one or more support elements and the one or more extendable elements are slidably or fixedly coupled to the second cutting member. The second cutting member is configured to adjust a position of the second cutting member relative to the first cutting member.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202080101693.7, filed on June 4, 2020, with the invention title of "Surgical Device Controllable by a Surgical Robot System". Technical Field

[0002] The present invention generally relates to a robotic system combined with a surgical device, and more particularly, to a surgical device integrated with a surgical robotic system for performing spinal surgery. Background Art

[0003] A herniated or degenerated intervertebral disc is a common condition in which a portion of the intervertebral disc, a cushion-like structure located between spinal vertebrae, bulges or protrudes beyond the normal margins of the disc and the spine. Herniated or degenerated intervertebral discs are thought to result from a loss of elasticity of the tissues including the intervertebral disc. They are typically associated with aging. Herniated or degenerated intervertebral discs and other degenerative disc diseases are also associated with spinal stenosis (narrowing of the bony and ligamentous structures of the spine). Although a herniated or degenerated intervertebral disc can occur anywhere along the periphery of the disc, it more often occurs in the posterior and posterolateral regions of the disc, where the spinal cord and spinal nerve roots reside. Compression of these nerve structures can lead to pain, paralysis, weakness, incontinence, and other neurological symptoms that can significantly affect basic daily activities and quality of life.

[0004] Temporary relief of pain associated with a herniated or degenerated intervertebral disc is typically obtained using conservative therapies, which include postural therapy (e.g., sitting or bending forward to reduce pressure on the spine), physical therapy, and pharmaceutical therapy to reduce pain and inflammation. When conservative therapies do not resolve a patient's symptoms, surgery may be considered to treat the structural source of the symptoms. Surgical treatment of a herniated or degenerated intervertebral disc typically involves open surgical procedures that require extensive dissection of the muscles, connective tissues, and bones of the patient's back to obtain adequate surgical exposure, and sometimes the surgical procedure requires the implantation of foreign bodies within the patient's body. Due to the presence of important neurovascular structures near the surgical site, these surgeries also expose the patient to a significant risk of complications. Discectomy is one such surgery. Discectomy surgically removes abnormal disc material that is compressing the nerve root or spinal cord. Discectomy can decompress the herniation by approaching the affected intervertebral disc and removing a portion of the disc and any loose disc fragments. To achieve adequate access to the affected intervertebral disc, a portion of the lamina or vertebral arch of the vertebra may be removed, thereby increasing the invasiveness of the surgery. When discectomy does not resolve a patient's symptoms, more radical measures may include disc replacement surgery or spinal fusion, which require complete discectomy and endplate stripping. Summary of the Invention

[0005] A brief overview of one or more examples is presented below to provide a basic understanding of the present disclosure. This Summary is not an extensive overview of all contemplated examples, nor is it intended to identify key or critical elements of all examples or to delineate the scope of any or all examples. Its purpose is to present some concepts of one or more examples in a simplified form as a prelude to the more detailed description presented below.

[0006] Systems and methods for performing surgical procedures using a surgical device controllable by a surgical robot system are described. The surgical device can be used to treat herniated or decompressed discs, disc degeneration, bone stripping, spinal fusion, spinal deformity, and vertebral fractures. Such surgical procedures include surgical robots and / or minimally invasive access or endoscopic access and removal of disc tissue. In some embodiments, a surgical device controllable by a surgical robot system is provided. The surgical device includes: a housing that can be coupled to the surgical robot system; a drive system that is at least partially mounted in the housing; and a shaft that is rotatably coupled to the drive system at a first end of the shaft. The surgical device further includes a tissue removal assembly coupled to a second end of the shaft. The tissue removal assembly includes a first cutting member having a plurality of rotatable blades. The first cutting member is coupled to the second end of the shaft. A cross-section of the first cutting member having the plurality of rotatable blades forms a polygon. The tissue removal assembly further includes: a second cutting member; one or more support elements that are slidably or fixedly coupled to the second cutting member; and one or more extendable elements that are slidably or fixedly coupled to the second cutting member. The one or more support elements and extendable elements are extendable and retractable to adjust the position of the second cutting member relative to the first cutting member.

[0007] In some embodiments, a surgical robot system is provided. The surgical robot system particularly includes a robot controller; a robotic arm controlled by the robot controller; and a surgical device. The surgical device includes: a housing that can be coupled to the surgical robot system; a drive system that is at least partially mounted in the housing; and a shaft rotatably coupled to the drive system at a first end of the shaft. The surgical device further includes a tissue removal assembly coupled to a second end of the shaft. The tissue removal assembly includes a first cutting member having a plurality of rotatable blades. The first cutting member is coupled to the second end of the shaft. A cross-section of the first cutting member having the plurality of rotatable blades forms a polygon. The tissue removal assembly further includes: a second cutting member; one or more support elements slidably or fixedly coupled to the second cutting member; and one or more extendable elements slidably or fixedly coupled to the second cutting member. The one or more support elements and extendable elements are extendable and retractable to adjust a position of the second cutting member relative to the first cutting member.

[0008] In some embodiments, a method for placing an intervertebral implant in a patient's spine using a robotic system is provided. The robotic system includes a robotic manipulator and an insertable surgical device coupled to the robotic manipulator to advance and insert the intervertebral implant into the spine. The method includes controlling movement of the insertable surgical tool to place the intervertebral implant along a desired trajectory. The method also maintains the desired trajectory of the discectomy procedure and controls the implantation of the intervertebral implant in the patient's spine such that the intervertebral implant is placed at a desired location. Controlling the implantation of the intervertebral implant includes causing autonomous movement of the insertable surgical device to place the intervertebral implant in the patient's spine until the intervertebral implant is within a predetermined distance of the desired location. Thereafter, manual operation of the insertable surgical device can be controlled until the intervertebral implant is placed at the desired location.

[0009] It should be understood that the systems and methods described herein can be used to remove tissue and insert an intervertebral implant into a patient during a discectomy. Thus, although tissue removal and insertion of an intervertebral implant during a discectomy are mentioned as an example throughout the text, the same systems and methods described herein can be used to treat any anatomy of a patient and / or to place any implant into a patient, for example, in the knee, hip, shoulder, spine, skull, and other parts of the body, etc. For example, the robotic controller and robotic manipulator can also be used to provide the trajectory of the pedicle of the spine, place pedicle screws for spinal implants, place rods, place other components, and / or drill guide holes or other procedures. Different end effectors or surgical devices can also be attached to the robotic manipulator for other procedures. In some cases, the end effector or surgical device can also have an articulated arm to insert the implant, that is, to place the implant in a desired position. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] To better understand the various aspects described, the following description should be referred to in conjunction with the following drawings, in which like reference numerals in all the drawings refer to corresponding parts.

[0011] Figure 1 An exemplary surgical robotic system for performing orthopedic surgery is shown.

[0012] Figure 2 Shows Figure 1 An exemplary robotic manipulator of the exemplary robotic surgical system.

[0013] Figure 3 An exemplary navigation system of the surgical robotic system and a surgical device coupled to the surgical robotic system for performing orthopedic surgery are shown.

[0014] Figure 4 An exemplary robotic arm of the surgical robotic system and an exemplary surgical device coupled to the robotic arm are shown.

[0015] Figures 5A to 5C An exemplary surgical device that can be controlled by the surgical robotic system to place the tissue resection assembly of the surgical device in different configurations is shown.

[0016] Figure 6 An exemplary surgical device for an intervertebral space during a discectomy is shown.

[0017] Figure 7 Is a schematic perspective view and a top view of a part of the lumbar spine.

[0018] Figure 8 Is Figure 6 An enlarged view and a cross-sectional view of a part of the surgical device.

[0019] Figure 9 Shows a plurality of exemplary cross-sectional shapes of a cutting member of an exemplary tissue removal assembly. Detailed Description

[0020] The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. For the purpose of providing a thorough understanding of the concepts, the detailed description includes specific details. It will be apparent, however, to one of ordinary skill in the art that the concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring such concepts.

[0021] Surgical procedures are typically performed manually by a surgeon. For example, in a spinal surgical procedure, a surgeon may need to manually remove tissue using a surgical device. To complete such a surgical procedure, the surgeon may need to insert the surgical device into the patient's spinal region and repeatedly cut the tissue. Sometimes, the surgeon may need to repeat the cutting operation dozens or even hundreds of times. Thus, for the surgeon, the surgical procedure can be very long and fatiguing. The extended surgical procedure also increases the risk of error and reduces the precision or accuracy of tissue cutting during the surgical procedure. Accordingly, there is a need to improve the efficiency, precision, and repeatability of surgical procedures by integrating surgical devices with surgical robotic systems. There is also a need to improve the surgical devices themselves such that tissue removal is more accurate, precise, and effective.

[0022] In some embodiments, the surgical device described in the present disclosure includes a tissue removal assembly having a first cutting member. The first cutting member includes a plurality of rotatable cutters or blades formed along a longitudinal direction of the first cutting member. A cross-section of the first cutting member forms a star-shaped polygon. The plurality of rotatable blades of the first cutting member, together with an auger on a shaft coupled to the first cutting member and an extendable second cutting member, provide a vortex effect flow control for controlling the flow of tissue and fluid (e.g., blood) removal during the performance of a surgical procedure. Thus, the disclosed first cutting member, extendable second cutting member, and auger on the shaft improve the flow control of tissue removal. Depending on one or more of the size of the outer tube, the size of the first cutting member, the size of the second cutting member, and the size of the auger on the shaft, tissue removal during flow control can be up to 0.1 cubic centimeters per minute (cc / min) to 10 cc / min.

[0023] In addition, the tissue removal assembly of the surgical device may further include one or more extendable elongate members, such as tubes and / or cables. Accordingly, the tissue removal assembly can be more easily inserted into the lumbar intervertebral disc. As disclosed in more detail below, the tissue removal assembly may further include a second cutting member. The second cutting member can be controlled (e.g., by a robotic system) to be in a retracted or deployed configuration. The disclosed first cutting member can be controlled (e.g., by a robotic system) to rotate at a desired speed and can thus fragment tissue on a stenotic or collapsed intervertebral disc before deploying the second cutting member. Accordingly, the first cutting member having multiple rotatable blades can also improve fragmentation of the intervertebral disc material and facilitate smoother removal of tissue and / or fluid from a collapsed intervertebral disc. In some embodiments, the surgical device may further include a shaft, a plurality of support elements, and a plurality of extendable elements. The support elements and the extendable elements may include, for example, cables having retracted and deployed configurations. One or more of these cables may be supported distally by a movable rigid element that confines the distal end of the cable at a fixed distance from the shaft of the surgical device. In some embodiments, the second cutting member of the tissue removal assembly may be coupled to the support elements and the extendable elements. The second cutting member includes, for example, rotatable blades, cutters, or a plurality of cutters to fragment tissue when the second cutting member is controlled (e.g., by a robotic system) to be partially or fully in a deployed configuration.

[0024] In some embodiments, the surgical device described herein includes a housing mechanically and electrically coupled to a robotic arm (e.g., a power connector for electrical connection), a tissue collection chamber, a steering mechanism, and a drive system (e.g., a motor configured to rotate at a variable speed of at least 1000 rpm). The surgical device may further include an inner shaft and an outer tube surrounding at least a portion of the inner shaft. In some embodiments, the outer tube has an angled distal end and a proximal end attached to the housing. The outer tube may have a length, for example, of from about 5 centimeters (cm) to about 40 cm. The average diameter of the outer tube surrounding at least a portion of the inner shaft is, for example, less than about 4 millimeters (mm). The inner shaft may include a blunt proximal end that may be surrounded by the outer tube and coupled to the drive system (e.g., a motor). The inner shaft may further include an elongate member extending through an opening at the distal end of the outer tube. The inner shaft may be coupled to the tissue removal assembly using, for example, a reinforcement ring.

[0025] In some embodiments, one or more support elements may be coupled proximally to the inner shaft and distally to the elongate member of the inner shaft. The elongate member may be engaged to the support element by, for example, a hinge mechanism. The hinge mechanism may be configured to generally limit relative movement between the elongate member of the inner shaft and the support element to a plane generally defined by the elongate member and the support element.

[0026] A robotic system can be controlled to perform surgeries, such as delicate spinal surgeries. One such spinal surgery can place pedicle screws in a patient's spine. When a patient requires a surgery involving the placement of pedicle screws, preoperative images and / or intraoperative images of the patient's spine are obtained. Then, the surgeon plans the positions for placing the pedicle screws based on the images and / or based on a 3D model generated from the images. The plan includes, for example, determining the position and orientation of each pedicle screw relative to the specific vertebra in which they are to be placed, such as by determining the desired positions in the images and / or 3D model. Once the plan is determined, it is transmitted to the robotic system for execution.

[0027] Generally, the robotic system includes a robotic manipulator (e.g., one or more robotic arms) that can position a tool guide above the patient and along a desired trajectory that aligns with the desired orientation or trajectory of the pedicle screw to be placed. The robotic system also includes a navigation system to determine the position of the tool guide relative to the patient's anatomy such that the robotic manipulator can place the tool guide along the desired trajectory according to the surgeon's plan. In some cases, the navigation system includes one or more tracking devices attached to the robotic manipulator and the patient such that the robotic system can monitor and respond to patient movement during the surgical procedure by moving the tool guide as needed to maintain the desired trajectory.

[0028] After the tool guide has been positioned to align with the desired trajectory, the robotic manipulator is controlled to maintain the alignment. Thereafter, the surgeon positions a cannula through the tool guide and adjacent to the vertebra. The surgeon inserts a conventional drilling tool into the cannula to drill a pilot hole for the pedicle screw. Then, the surgeon removes the drilling tool and drives the pedicle screw into position in the pilot hole using a pedicle screw driver. In this method, the robotic manipulator may not be fully utilized because the robotic manipulator plays little role in drilling the pilot hole or inserting the pedicle screw. Various embodiments of the surgical devices disclosed in this disclosure can be controlled by the robotic system to improve or enhance the use of the robotic manipulator in various spinal surgeries.

[0029] Figure 1 An exemplary surgical robotic system 100 for performing orthopedic surgeries is shown. In some embodiments, the robotic system 100 includes a robotic manipulator 40 and a navigation system 10. Figure 2 An exemplary robotic manipulator 40 is shown. Figure 3 An exemplary navigation system 10 and a surgical device 20 coupled to the robotic manipulator 40 of the robotic system 100 are shown. Refer Figure 1 , Figure 2 and Figure 3, shows a surgical robot system 100. The surgical robot system 100 can be used for various surgical procedures, including but not limited to knee, hip, and spinal surgical procedures. For example, the surgical robot system 100 can be coupled to a surgical device (e.g., the surgical device 20 shown in Figure 3 to perform tissue removal procedures, intervertebral implant positioning, or the trajectory or placement of screws or rods, other types of implants placed in the spine, bone dissection, dural repair, and / or other spinal procedures. For different procedures, the surgical device 20 coupled to the robot system 100 can be the same or different.

[0030] As Figures 1 to 3 shown, in some embodiments, the robotic manipulator 40 of the surgical robot system 100 includes a base 51, a robot controller 90, a robotic arm 50, and one or more displays 13A (one such display is shown). The robotic arm 50 can include a base chain 52 rotatably coupled to the base 51 and a plurality of arm chains 53 extending continuously from the base chain 52 to a distal end 54. The arm chains 53 can pivot and / or rotate about a plurality of joints in the robotic arm 50 with at least three degrees of freedom. In a preferred embodiment, the arm chain 52 has seven degrees of freedom. Figure 3 Also shown is a surgical device 20 coupled to the distal end 54 of the robotic arm 50. The surgical device 20 can be controlled by the robot system 100 (e.g., controlled by the robot controller 90 using the arm chains 53) to perform various spinal surgical procedures. The surgical device can be a discectomy surgical tool, an inserter for an intervertebral implant, an inserter for a pedicle screw, a bone dissector, a saw, a drill, etc. The surgical device 20 can be pivotally connected to the distal end 54 of the robotic arm 50. Another preferred embodiment can be that the base chain 52 is not connected to the base 51, but the base chain 52 is separately locked to the bedside (not shown). In this embodiment, the communication between the base 51 and the robotic arm 50 can be via a Bluetooth or Wi-Fi connection. One embodiment of the robotic arm 50 is manufactured by AUBORoboticsChina, located on the 3rd floor of Shilong Sunshine Building, No. 98, Lianshihu West Road, Beijing, China, or its US office AUBORoboticsUSA, located at Room 203, 2704 Chekokee Farm Way, Knoxville, TN 37920, USA.

[0031] Referring to Figures 1 to 3 , the robot controller 90 can be configured or programmed to be in the surgical device 20 (e.g., as Figure 3During the manipulation (as shown), control or guidance of the robotic arm 50 is provided to a user (e.g., a surgeon). In one embodiment, using the robot controller 90, the robotic arm 50 can operate autonomously based on a predefined robotic arm trajectory or path and / or other predefined movements to perform a surgical procedure. Such movements can be defined during and / or prior to the surgical procedure. In some embodiments, the surgical robotic system 100 (as Figure 1 shown) can allow a combination of manual control and autonomous control of the robotic arm 50. For example, the surgical robotic system 100 can be configured or programmed to operate in a manual mode and / or a semi-automatic mode. In the manual mode, the user applies a force to the surgical device 20 to move the robotic arm 50. In the semi-automatic mode, the user holds the suspended console to control the robotic arm 50 to automatically follow a tool path or tool movement.

[0032] Figures 1 to 3 The surgical robotic system 100 is shown having a single robotic arm 50. It should be understood that one or more additional robotic arms can be integrated or included in the robotic system 100. In some embodiments, the robotic system can include more than one robotic arm configured or programmed to perform different operations or functions of a procedure simultaneously. For example, a first robotic arm can be controlled to perform a discectomy, and a second robotic arm can be controlled to perform the alignment and trajectory of pedicle screws.

[0033] As Figures 1 to 3 shown, one or more displays 13A can display, for example, one or more user interfaces to provide interaction between the user and the robot manipulator 40. For example, the display 13A can assist in the configuration or programming of the robot controller 90 to define the robotic arm trajectory, provide visual and / or auditory feedback to the user, monitor the movement of the robotic arm 50, etc.

[0034] As Figure 1 and Figure 3 shown, in some embodiments, the surgical robotic system 100 includes a navigation system 10. In some embodiments, the navigation system 10 can be configured to track the movement of various objects in an operating room (e.g., an operating theater) relative to a target coordinate system. These objects include, for example, the surgical device 20, the patient's anatomical structures of interest, such as an intervertebral disc space, a pedicle, a vertebra, the dura mater, and / or one or more of other objects. The navigation system 10 can track these objects and display their relative positions and orientations in the target coordinate system to the surgeon. One or more displays 13B can be used to display this tracking data. In some embodiments, the navigation system 10 can track these objects to constrain the movement of the surgical device 20 relative to one or more virtual boundaries associated with the patient's anatomical structure and defined relative to the target coordinate system (e.g., through coordinate system transformations used in surgical navigation).

[0035] In some embodiments, the navigation system 10 includes a computer cart assembly 14 that houses a navigation controller 15. The navigation controller 15 and the robot controller 90 can together form a coordinated control system of the surgical robot system 100. The navigation system 10 can also include a navigation interface that can operably communicate with the navigation controller 15. The navigation interface includes a display 13B adjustably mounted to the computer cart assembly 14. Input devices such as a keyboard and a mouse 16 can be used to facilitate user interaction with the navigation controller 15 (e.g., input information to the navigation controller), or alternatively to select / control certain aspects of the navigation controller 15. It should be understood that other input devices can also be used to facilitate user interaction with the navigation controller 15. Such input devices can include a touch screen (not shown), a joystick, a voice control system, etc.

[0036] Reference Figure 3 , the navigation system 10 can also include a locator 11 and one or more tracking devices 12. The locator 11 can communicate with the navigation controller 15 (e.g., using wired or wireless communication to provide data to and / or receive data from the navigation controller 15). In Figure 3 the illustrated embodiment, the locator 11 is an optical locator and includes a camera unit (e.g., a sensing device). The camera unit has a housing that houses one or more optical position sensors. In some embodiments, at least two optical position sensors are used. In some embodiments, three or more optical position sensors are used (e.g., to improve position sensing accuracy). The optical position sensors can be, for example, individual charge-coupled devices (CCDs). In some embodiments, the camera unit of the locator 11 is mounted on an adjustable arm to position the optical position sensors corresponding to the fields of view of one or more tracking devices 12. The fields of view associated with the optical position sensors of the locator 11 are preferably free of obstacles such that the sensing of position or orientation information is not affected.

[0037] In some embodiments, the locator 11 can include a three-dimensional (3D) sensor that can obtain imaging data associated with the patient's internal body (e.g., the patient's organs, tissues, spine, etc.). Such a 3D sensor can penetrate the patient's body and thus improve the accuracy of the surgical procedure. The 3D sensor can also be used to provide intraoperative images of the device position and trajectory without the need to confirm using standard C-arm fluoroscopy equipment. In some embodiments, the sensing or imaging device (not shown) can be a portable magnetic resonance imaging (MRI), which is an independent device or can be part of an attachment of the robotic arm 50 to provide intraoperative images of the device position and trajectory without having to confirm using standard C-arm fluoroscopy equipment. It should be understood that although Figure 1 and Figure 3The navigation system 10 and the robotic manipulator 40 are illustrated as two separate systems, but they can be integrated or combined in any desired manner. For example, one or more components or subsystems of the navigation system 10 (e.g., the locator 11) can be integrated with the robotic arm 50.

[0038] Referring Figure 3 , the navigation system 10 can also include a plurality of tracking devices 12, also referred to herein as trackers. In some embodiments, the tracking devices 12 can include one or more trackers coupled to different parts of the surgical robotic system 100. For example, the tracker 12 can be coupled to the patient, to the base of the robotic system, and to the surgical device. In Figure 3 the illustrated embodiment, the tracker 12 can be coupled to the patient's skin, intervertebral disc space, pedicle, vertebra, or spinous process. In some embodiments, the tracker 12 is securely attached to a section of the intervertebral disc space, pedicle, vertebra, bone, patient skin, etc. by bone screws. In some embodiments, clamps on the spinous process or other parts of the spine can be used to attach the tracker 12. In additional embodiments, the tracker 12 can be mounted to other tissue types or parts of the patient's anatomy. The position of the tracker 12 relative to the anatomy to which it is attached can be determined by positioning techniques, such as point-based positioning, where a digitizing probe 17 (e.g., a navigation indicator with its own markers) is used to trigger bony landmarks on the bone or to touch several points on the bone for surface-based positioning. Conventional positioning techniques can be employed to correlate the position of the tracker 12 with the patient's anatomy, such as the intervertebral disc space, pedicle, or vertebra being treated. The digitizing probe 17 can be a device separate from the surgical robotic system 100 or can be integrated with the surgical robotic system 100.

[0039] As described above, the tracker 12 can also be coupled to the base of the surgical robotic system 100. Such a tracker 12 is referred to as a base tracker. For example, the base tracker 12 can be coupled to the base 51 to track the position of the surgical device 20. In some embodiments, as Figure 3 shown, a separate tracker 12 can be coupled to the surgical device 20. For example, the tracker 12 can be integrated into the surgical device 20 during manufacture or can be separately mounted to the surgical device 20 using a coupler 55 during the preparation of the surgical procedure. Regardless of the manner in which the tracker 12 is coupled to the surgical device 20, the base tracker 12, the tracker 12 directly mounted on the surgical device 20, other trackers, or a combination thereof can be used to track the operating end of the surgical device 20. The operating end of the surgical device 20 can be the distal end of an attachment of the surgical device 20. Such an attachment can include a discectomy surgical tool, an inserter for insertion between vertebral bodies, a screwdriver for placing pedicle screws, an ablation device, a saw, a drill, a knife, a dissector, a Kirschner wire, a guide pin, etc.

[0040] In some embodiments, tracker 12 is a passive tracker. For example, each tracker 12 has at least one passive tracking element or marker for reflecting light from locator 11 back to the optical sensor included in locator 11. In some embodiments, tracker 12 is an active tracker and may have a light emitting diode or LED that emits light (such as infrared light) towards the optical sensor of locator 11. Based on the received light signal, navigation controller 15 uses, for example, triangulation techniques to generate data indicating the relative position and orientation of tracker 12 relative to locator 11. In some cases, more or fewer markers may be used. For example, in the case where the object being tracked can rotate about a wire, two markers can be used to determine the orientation of the wire by measuring the positions of the markers at different locations around the wire. It should be understood that although described above as utilizing optical tracking techniques, locator 11 and tracker 12 can alternatively or additionally utilize other forms of tracking to track the object, such as electromagnetic tracking, radio frequency tracking, inertial tracking, three-dimensional tracking, or a combination thereof, etc.

[0041] In some embodiments, robot controller 90 and navigation controller 15 may each or jointly include one or more memories adapted to store data and computer-readable instructions, such as non-transitory computer-readable memory, local memory, external memory, cloud-based memory, flash memory, or any other suitable form of memory. Robot controller 90 and navigation controller 15 may each or jointly include one or more processors, such as a microprocessor, for processing instructions or algorithms stored in the memory to perform the functions described herein. The processor can be any type of processor, microprocessor, or multiprocessor system, or an ASIC system, discrete circuit system, and / or other suitable hardware, software, or firmware capable of performing the functions described herein. Robot controller 90 and navigation controller 15 may be carried by robot manipulator 40, computer cart assembly 14, and / or may be mounted to any other suitable location. Robot controller 90 and / or navigation controller 15 may be loaded with hardware, software, or firmware. For example, navigation controller 15 may be loaded with software that converts the signals received from locator 11 into data representing the position and orientation of the object being tracked. In some embodiments, data associated with each surgery may be stored in various types of memories within robot controller 90. For example, after at least 20 surgeries, robot controller 90 may have some built-in artificial intelligence from a set of data associated with previous surgeries to guide the doctor in his or her future surgeries.

[0042] In some embodiments, prior to the start of a surgical procedure, additional data is loaded into the navigation controller 15. Based on the position and orientation of the tracker 12 and the previously loaded data, the navigation controller 15 determines the position of the operative end of the surgical device 20 and the orientation of the surgical device 20 relative to the tissue to which the operative end is to be applied. The additional data can include calibration data, such as geometric data that correlates the position and / or orientation of the tracker 12 or its markers 80 with the operative end of the surgical device 20. This calibration data can also be determined preoperatively or intraoperatively, such as by using a calibration probe or calibration notch on the tracker 12 of known geometry to determine the position of the operative end of the surgical device 20, e.g., relative to its own tracker or relative to the base tracker 12. The additional data can include localization data, such as transformation data that correlates the tracker 12 with the patient's anatomy or its 3D model. In some embodiments, the navigation controller 15 sends this data to the robotic controller 90 via a communication link (e.g., a wired or wireless communication link). The robotic controller 90 can then use this data to control the robotic arm 50.

[0043] In some embodiments, the navigation controller 15 also generates image signals representing the relative position and / or orientation of the operative end of the surgical device 20 relative to an object of interest (e.g., tissue, spine, intervertebral disc). These image signals can be provided or communicated to one or more displays 13B. Based on these signals, the displays 13B can generate images that allow the surgeon and staff to observe the relative position and / or orientation of the surgical device 20 relative to the surgical site. As discussed above, the displays 13B can include touchscreens or other input / output devices that facilitate user interaction (e.g., input commands that allow the surgeon to visualize).

[0044] In Figures 1 to 3In the illustrated embodiment, using the navigation system 10, the position and / or orientation of the surgical device 20 can be determined. The determination can be based on tracking the position of the base 51 by the base tracker 12, on the connector encoder data associated with the connector of the robotic arm 50, and / or on the known geometric relationship between the surgical device 20 and the robotic arm 50 to calculate the position / orientation of the surgical device 20. Thus, the locator 11 and one or more trackers 12 are capable of determining the position / orientation of the surgical device 20 and the patient's anatomy. Accordingly, the navigation system 10 is provided with the relative relationship between the surgical device 20 and the patient's anatomy. One such navigation system is described in more detail in U.S. Patent No. 9,668,820, entitled "INTEGRATED SURGICAL DEVICE COMBINING INSTRUMENT, TRACKING SYSTEM AND NAVIGATION SYSTEM", filed on February 8, 2012, and granted to Neubauer (BrainLabs), the content of which is incorporated herein by reference in its entirety.

[0045] During a surgical procedure, for certain surgical tasks, the user can manually manipulate (e.g., move or cause to move) the robotic arm 50 to direct, guide, control, activate, or operate the surgical device 20 to perform a surgical procedure on the patient. The surgical procedure can include, for example, tissue removal, cutting, drilling, implant mounting, repair, bone stripping, guiding, etc. As the user manipulates the surgical device 20, the navigation system 10 tracks the position / orientation of the surgical device 20 and / or the robotic arm 50 and provides haptic feedback (e.g., force feedback) to the user to limit the user's ability to move (or cause to move) the surgical device 20 beyond one or more predefined virtual boundaries that are located (or mapped) to the patient's anatomy. The ability of the robotic system 100 to keep the user's manipulation of the surgical device 20 within the predefined virtual boundaries results in a highly precise and repeatable surgical procedure, such as including tissue removal, cutting, drilling, guiding, and implant mounting.

[0046] In one embodiment, the robotic arm 50 operates in a passive manner and provides haptic feedback when a surgeon attempts to move the surgical device 20 beyond a virtual boundary. The haptic feedback is generated by one or more actuators (e.g., joint motors) in the robotic arm 50 and transmitted to the user through a joint transmission device (such as an electromechanical transmission device). When the robotic arm 50 does not provide haptic feedback, the robotic arm 50 can be freely moved by the user. In other embodiments, the robotic arm 50 is manipulated by the user in a similar manner, but the robotic arm 50 operates in an active manner. For example, the user applies a force to the surgical device 20, and the force is measured by a force / torque sensor. The robotic arm 50 simulates the desired movement of the user based on the measurement from the force / torque sensor. In some embodiments, the robotic arm 50 operates autonomously and the user does not need to manually operate the surgical device 20.

[0047] Figure 4 A partial view of an exemplary robotic arm 50 and an exemplary surgical device 20 coupled to the robotic arm 50 is shown. Figures 5A to 5C An exemplary surgical device 20 that can be controlled by the surgical robot system 100 to place the tissue resection assembly 62 of the surgical device 20 in different configurations or arrangements is shown. The surgical device 20 can be, for example, a discectomy surgical device (e.g., Figure 4 the device shown in). As Figure 4 shown, the surgical device 20 can be coupled to the distal end 54 of the robotic arm 50 ( Figure 4 a partial robotic arm 50 is shown). More specifically, a robotic system coupler 55 is disposed between the surgical device 20 and the distal end 54 of the robotic arm 50. Figure 2 a partial robotic arm 50

[0048] In some embodiments, the robotic system coupler 55 mechanically couples the housing 32 of the surgical device 20 to the robotic arm 50. For example, the robotic system coupler 55 can be configured to mechanically attach the surgical device 20 interchangeably to any selected surgical device used in a surgery. For example, the robotic system coupler 55 can be configured to include a detachable adapter for attaching different types of surgical devices. The robotic system coupler 55 can also include a universal adapter that can change size and shape to fit different types of surgical devices. The robotic system coupler 55 can include, for example, a flexible coupler and / or a rigid coupler to firmly attach the surgical device 20 to the robotic arm 50. Such a robotic system coupler 55 can be implemented using, for example, hinge-based coupling, gear-based coupling, fluid-based coupling, magnetic-based coupling, joint-based coupling, or a combination thereof. The surgical device 20 can be a discectomy surgical device, an inserter for intervertebral implants, a screwdriver for pedicle screws, a periosteal elevator, a dural repair instrument, an ablation device, a drill, a saw, etc. Figure 4Shown is a surgical device 20 as a discectomy surgical device for removing tissue from an intervertebral disc space, implanting an implant, drilling and implanting an implant, removing bone tissue, repairing tissue, or providing an ablation procedure. It should be understood that although Figure 4 shown is one way in which the surgical device 20 is attached, coupled, or integrated with a surgical robotic system 100 by a robotic arm 50 (shown in Figure 1 and 3 ), the surgical device 20 can also be attached, coupled, or integrated with the surgical robotic system 100 in any other desired way (e.g., by hinges, screws, gears, connectors, magnetics, quick-release attachments, etc.).

[0049] In some embodiments, the robotic system coupler 55 also electrically couples a drive system (not shown) of the surgical device 20 to the surgical robotic system via a coupling interface 65 included in a housing 32 of the surgical device 20. For example, the robotic system coupler 55 can include internal electrical wiring such that power cables or wiring extend from the robotic arm 50 to the drive system of the surgical device 20 via the coupling interface 65. Thereby, the surgical device 20 can be provided with power to operate various components or subsystems of the surgical device 20 (e.g., a rotating shaft 61 and an operating tissue removal assembly 62). In some embodiments, both the coupling interface 65 and the robotic system coupler 55 can include corresponding or matching power adapters, interfaces, sockets, etc. such that power cables or wiring can be easily connected from the robotic arm 50 to the surgical device 20. The coupling interface 65 will be further described below.

[0050] In some embodiments, the robotic system coupler 55 can also communicatively couple the surgical device 20 to the surgical robotic system 100. For example, the robotic system coupler 55 can include internal electrical wiring such that one or more signal cables or wiring extend from the robotic arm 50 to the drive system (not shown) of the surgical device 20 via the coupling interface 65. Thereby, the surgical device 20 can be provided with control signals to operate various components or subsystems of the surgical device 20 (e.g., a rotating shaft 61 and an operating tissue removal assembly 62). Additionally, the surgical device 20 can also provide feedback signals to a robotic controller 90 of the surgical robotic system by using the robotic system coupler 55 (as shown in Figure 1 and Figure 3 ). In some embodiments, both the coupling interface 65 and the robotic system coupler 55 can include corresponding or matching signal adapters, interfaces, sockets, etc. such that signal cables or wiring can be easily connected from the robotic arm 50 to the surgical device 20. In some embodiments, the surgical device 20 can wirelessly communicate with the robotic controller 90 (shown in Figure 1 and Figure 3 ) using, for example, Bluetooth or Wi-Fi technology.

[0051] In some embodiments, such as Figure 4 and Figures 5A to 5C shown, in these embodiments, a surgical device 20, which is a discectomy surgical device, includes a housing 32, a drive system (not shown), a shaft 61, an outer tube 60, and a tissue removal assembly 62. The housing 32 can be coupled to a robotic arm 50 using a robotic system coupler 55. As described above, the robotic system coupler 55 can use any desired mechanical coupling mechanism to secure the surgical device 20 to the robotic arm 50. Accordingly, one or both of the housing 32 of the surgical device 20 and the distal end 54 of the robotic arm can have a mating mechanism to facilitate such coupling. Such a mating mechanism can include, for example, a mechanism associated with a hinge-based, gear-based, fluid-based, screw-based, connection-based, magnetic-based coupling, or a combination thereof.

[0052] As described above, the surgical device 20 can include a drive system ( Figure 4 not shown in). In some embodiments, the drive system is partially or fully mounted in the housing 32. The drive system can be electrically and communicatively coupled, for example, to a robotic controller 90 or a surgical robotic system 100. The drive system can be controlled by the robotic controller 90 to operate the surgical device 20, such as a discectomy surgical device and / or other accessories of the device 20. The drive system can include a motor having a variable speed or a constant speed. The robotic controller 90 can transmit signals to the drive system to operate, for example, the shaft 61 and the tissue removal assembly 62. As discussed in more detail below, the tissue removal assembly 62 can include a first cutting member 37 and a second cutting member 36. The two cutting members can be independently controlled or coordinated with each other by the drive system using signals transmitted from the robotic controller 90 or mechanically controlled. In some embodiments, in addition to the drive system, the housing 32 can include one or more control components. Additional control components (e.g., a separate controller) can be configured to control the tissue removal assembly 62 and other optional features of the surgical device 20.

[0053] As described above, the robotic system coupler 55 can electrically and communicatively couple the surgical device 20 to the surgical robotic system through a coupling interface 65. The coupling interface 65 can be used to bring a power source from the robotic arm 50 to the surgical device 20, including but not limited to the switch state of the motor of the surgical device 20, changing the motor speed of the motor of the surgical device 20, and / or controlling the maneuverability of the steering mechanism 38 (in Figure 6(shown in). In some embodiments, the coupling interface 65 may include one or more electrical contacts to bring a direct current (DC) power source between 5 volts and 30 volts to power the motor in the housing 32 of the surgical device 20. In some embodiments, the coupling interface 65 may also change the motor speed and / or the direction of movement of the tissue removal assembly 62. In some embodiments, as described above, the coupling interface 65 may also provide mechanical fixation to couple any surgical device 20 to the distal end 54 of the robotic arm 50.

[0054] In some embodiments, the surgical device 20 may be a discectomy surgical device 30, which includes a shaft 61, an outer tube 60, a collection chamber 34, and a tissue removal assembly 62. The shaft 61 is rotatably coupled to a drive system at a first end. The shaft 61, sometimes also referred to as the inner shaft, is at least partially surrounded by the outer tube 60. In some embodiments, the shaft 61 may include an elongated member having threads that are configured to convey the removed tissue. As Figure 4 and Figures 5A to 5C shown, the threads 35 may form an integral part of the shaft 61 (e.g., manufactured together). The threads 35 may be, for example, an auger or an Archimedes screw for conveying the tissue removed from the surgical site to the collection chamber 34. As will be described in more detail below, the tissue may be removed by the tissue removal assembly 62, which may include a first cutting member 37 and a second cutting member 36. For example, the second cutting member 36 may include one or more rotatable cutting tips for grinding the tissue and removing the tissue from the surgical site. And the first cutting member 37 may include a plurality of rotatable blades for cutting the tissue within a narrow intervertebral disc space. The first cutting member 37 may be coupled to the second end of the elongated member of the shaft 61. Thus, the drive system (e.g., via the robotic controller 90) may be controlled to operate the shaft 61, which in turn rotates the first cutting member 37 of the tissue removal assembly 62.

[0055] Figures 5A to 5CDepicts an embodiment of a surgical device 20 in different configurations or arrangements. As shown, the surgical device 20 can be a discectomy surgical device 30 that can be controlled by a robotic controller 90 of a surgical robotic system 100 to place the tissue removal assembly 62 of the surgical device 20 in different configurations. In this embodiment, the surgical device 20 includes an outer tube 60 coupled to a housing 32 at a first end. The outer tube 60 surrounds at least a portion of a shaft 61 (e.g., a cable) attached to the tissue removal assembly 62. As described above, the shaft 61 is coupled to a drive system (e.g., a motor) and is thus rotatable. The outer tube 60 can be static and non-rotatable itself. In some embodiments, the surgical device 20 may not have an outer tube, and the shaft 61 may be inserted into the lumen of a cannula or other access device. In some embodiments, the outer tube 60 can surround a portion or the entire shaft 61. The outer tube 60 can also have a second end. The second end can have an opening such that the removed tissue or fluid can be collected through the opening and conveyed within the outer tube 60 back to the collection chamber 34. In some embodiments, the second end of the outer tube 60 can also have a sharp cutting edge to further enhance the cutting ability of the surgical device 20, which will be described in more detail below.

[0056] Figure 4 and Figures 5A to 5C Also shown is the tissue removal assembly 62, examples of which will be described in more detail below. The tissue removal assembly 62 includes a first cutting member 37 and a second cutting member 36. Using one or both of the two cutting members, the tissue removal assembly 62 can be configured to more effectively and precisely peel, crush, cut, chop, grind, deburr, debride, desquamate, emulsify, split, or otherwise remove tissue. One or both of the cutting members of the tissue removal assembly can rotate at a constant or different speed. Emulsification, for example, includes forming a suspension of tissue particles in a medium, which can be an existing liquid at the target site, a liquid added through the discectomy surgical device, and / or a liquid generated by tissue distension. Tissue removal can also encompass removing blood. In some embodiments, the surgical device 20 can be a discectomy surgical device, which can also include, but is not limited to, a motor, a power source or power interface, a motor controller, a tissue delivery assembly, an energy delivery or cryotherapy assembly, a therapeutic agent delivery assembly, a light source, and / or one or more fluid seals configured to rotate or move the tissue removal assembly 62. The tissue delivery assembly can include, for example, a suction assembly and / or a mechanical extraction assembly. One or more of these components can act through the outer tube 60 to manipulate the tissue removal assembly 62 and / or other components distal to the housing 32, or directly from the housing 32.

[0057] In as Figure 4 and Figures 5A to 5CIn some of the embodiments shown, the surgical device 20 can be a discectomy surgical device 30, which further includes a tissue collection chamber 34 mounted together with a housing 32. The collection chamber 34 can be fluidly connected to the tissue removal assembly 62, for example, through the inner lumen of a shaft 61. The inner lumen can be a hollow space, slot, tube, or dedicated passage for passing substances such as tissue, fluid, cables, wiring, etc. In some embodiments, the collection chamber 34 collects the tissue and / or fluid comminuted by the tissue removal assembly 62 and conveys it through the inner lumen from the intervertebral disc space 110 (shown in Figure 6 through the rotating drive shaft 61 and a thread 35 (e.g., a drill bit) to the collection chamber 34. In some embodiments, the collection chamber 34 includes one or more collection ports 45. The collection ports 45 can include one or more removable caps or plugs. The collection ports 45 are capable of conveying the removed tissue or fluid out of the collection chamber 34 through, for example, one or more conduits or tubes coupled to the collection chamber 34 at the collection ports 45.

[0058] In some embodiments, the surgical device 20 can be controlled by a robotic arm 50. Thus, the surgical device 20 can be used in surgical and / or percutaneous spinal surgery procedures, such as interbody fusion surgery procedures, minimally invasive or open discectomy, minimally invasive or open laminectomy, etc. Such a surgical device 20 is described as a discectomy surgical device in Figure 4 , Figures 5A to 5C and Figure 6 . The surgical device 20 can include a proximal housing 32 and a distal tissue removal assembly 62, which is connected to the housing 32 by an outer tube 60 having a longitudinal inner lumen therethrough. In some embodiments, the housing 32 can also be shaped (e.g., as shown in Figure 4 and Figures 5A to 5C ) with a first end of smaller size and a second end of larger size. Such a shape can be easily coupled to the robotic arm 55 and / or can be easily manually operated by a user (e.g., the user can easily operate the surgical device 20 by holding the smaller end of the housing 32). Optionally, the outer tube 60 can include an endoscopic port or inner lumen for visualizing tissue during a surgical procedure. In some variants, the outer tube 60 can be straight, or can have one or more preformed curves or angles, or can be manipulable with the movements from the robotic arm 50. As described above, the housing 32 can include a coupling interface 65, which has a quick attachment and detachment mechanism implemented by the user. For example, the housing 32 includes electrical contacts within the coupling interface 65, which can be used to bring a power source to actuate / operate components of the tissue removal assembly 62 (e.g., a first cutting member 37 and a second cutting member 36), as well as a mechanism for navigating the tissue removal assembly 62. In some variants, the navigation and movement of the surgical device 20 can be precisely controlled by the robotic arm 50.

[0059] As described above, in some embodiments, the surgical device 20 can be a discectomy surgical device 30, which can also include a collection chamber 34. The collection chamber 34 can be transparent. For example, as Figure 6 depicted, the housing 32 can be mounted with or include the collection chamber 34. The collection chamber 34 can be in fluid or tissue communication with the tissue removal assembly 62 through the lumen between the rotary shaft 61 and the outer tube 60. Tissue and / or fluid removed (e.g., peeled, pulverized, cut, dissected, etc.) by the tissue removal assembly 62 can be transported by the tissue delivery assembly (e.g., the lumen within the shaft 61 and the outer tube 60) through the rotary shaft 61 to the collection chamber 34. An embodiment of such transportation has been described above. In some embodiments, a vacuum source can be used to aspirate tissue and / or fluid from the target tissue site into the collection chamber 34. Some tissue removal devices can have multiple collection chambers, some of which can be used as fluid reservoirs for tissue infusion, and some of which can be used to store tissue samples removed by the tissue removal assembly 62. One or more collection chambers can be located at the distal or proximal portion of the housing 32, as Figure 6 shown, or can be located within the housing 32. Similar to the above description, one or more collection chambers 34 can include a collection port 45 having a removable cap or plug. Optionally, a portion of the collection chamber 34 can be configured as a magnifier, which can be used for visual inspection of any collected samples. In some variants, the removable plug or cap of the collection port 45 itself can be a magnifier. The collection chamber 34 can be made of an optically transparent material such as polycarbonate, acrylic, etc.

[0060] An example of the distal portion of the outer tube 60, the shaft 61, and the tissue removal assembly 62 of a surgical device (e.g., a discectomy surgical device) is shown in Figure 8 In some embodiments, the end portion (e.g., the distal portion) of the outer tube 60 includes a tip 63. The tip 63 is disposed closer to the tissue removal assembly 62 (shown in Figure 4 ) than to the housing 32. In some variants, the distal portion of the outer tube 60 can include an insulating polymer sheath or tube, which can prevent heat generated by the rotating mechanism within the outer tube 60 from reaching the outer portion of the outer tube 60, as this heat may thermally damage tissue. The outer portion of the outer tube 60 can come into contact with the patient's tissue. The insulating sheath can be located at the area of the outer tube 60 that has the greatest likelihood of contacting tissue.

[0061] In some embodiments, the tip 63 of the outer tube 60 includes a cutting edge 64, which improves the ability to further fragment or cut the tissue removed by the tissue removal assembly 62. In some embodiments, as Figure 8As shown, the cross-sectional dimension of the end portion of the outer tube 60 having the tip 63 is larger than that of the other portions of the outer tube 60. For example, the cross-sectional dimension of this end portion can gradually increase from the other portions of the outer tube 60 to the tip 63. This end portion can have, for example, a beveled shape as Figure 8 shown. Such an end portion having a sharp cutting edge 64 can further improve the cutting efficiency and precision of the surgical device 20 (such as a discectomy surgical device).

[0062] In some embodiments, the tip 63 can be welded, brazed, soldered, adhered, and / or crimped to the distal portion of the outer tube 60. Optionally, the tip 63 can be integrally formed with the distal portion of the outer tube 60. The tip 63 can be made of stainless steel (e.g., 440C stainless steel, 440FSE stainless steel, or 304 stainless steel), and can be heat-treated to RC55 - 60 with a bright finish that can be passivated according to the ASTM - A967 standard. The outer tube can also be made of a variety of materials, such as other metallic materials (e.g., nitinol, cobalt-chromium alloy, tungsten, etc.) and / or polymeric materials (e.g., PEEK, polyimide, aramid, polyethylene, etc.), as the case may be.

[0063] Referring to Figure 8 , the tissue removal assembly 62 can extend distally from the outer tube 60 (e.g., from the tip 63 of the outer tube 60). The tissue removal assembly 62 can be any of the tissue removal assemblies described above, as well as any of the tissue removal assemblies described below. As Figure 8 shown. The tissue removal assembly 62 can include one or more extendable elements 66 (e.g., annular extendable elements), one or more support elements 67 (e.g., annular support elements), a first cutting member 37, and a second cutting member 36. In some embodiments, the second cutting member 36 can engage the annular portions of one or more support elements 67 and one or more extendable elements 66. In such an arrangement, adjusting the length and position of one or more extendable elements 66 can change or adjust the position and orientation of the second cutting member 36 and one or more support elements 67. In other variations, one or more support elements 67 can be adjusted independently of the length and position of one or more extendable elements 66. Any number of extendable and support elements can be present, and the extendable and / or support elements can or can not loop through the cutting element. For example, the extendable element 66 can not loop through the second cutting member 36 (e.g., alternatively can be attached to the second cutting member as a single strand), while one or more support elements 67 loop through the second cutting member 36. The extendable element 66 and / or the support element 67 can be slidably or fixedly coupled to the second cutting member 36.

[0064] The tissue removal assembly 62 can also include a first cutting member 37. AsFigure 8 As shown, in some embodiments, the first cutting member 37 includes an elongated member (e.g., a columnar member) having a plurality of rotatable blades 37A, 37B, 37C, etc. The rotatable blades may be formed along the longitudinal direction of the elongated member. The rotatable blades may form an integral part of the elongated member of the first cutting member 37 or may be individually mounted to the elongated member of the first cutting member 37. Thus, the rotatable blades may rotate with the first cutting member 37 in a synchronous manner (e.g., at the same speed) or an asynchronous manner (e.g., at different speeds). The rotation of the first cutting member 37 and / or its rotatable blades may be controlled by the drive system of the surgical device 20 and / or any other controller, which in turn may be controlled by the robotic controller 90 of the robotic system. In as Figure 8 shown, in some embodiments, the rotatable blades (e.g., 37A-C, etc.) of the first cutting member 37, the second cutting member 36, and the drill 35 along the shaft 61 may provide a flow control vortex effect to bring tissue or fluid from the surgical site to the collection chamber 34. Although Figure 8 rotatable blades having straight edges along the longitudinal direction of the first cutting member 37 are shown, it should be understood that curved edges may also be implemented as needed.

[0065] Furthermore, in some embodiments, the plurality of rotatable blades of the first cutting member 37 may form a cross-section having a polygonal shape. In Figure 8 the example shown, the cross-section of the first cutting member 37 forms a star polygon. The star polygon has eight protrusions or corners corresponding to the eight rotatable blades. Each of the eight protrusions of the cross-section forms an angle of approximately 90 degrees. As described above, the rotatable blades having such a star polygon cross-section can improve tissue cutting efficiency and accuracy, thereby enhancing the overall efficiency of the surgical device 20. Additionally, when the surgical device 20 is controlled by a robotic system, the efficiency of the surgery can be significantly improved. For example, compared to a human user manually repeating the insertion and cutting operations hundreds of times using a surgical tool, the mechanically controlled surgical device disclosed in the present disclosure may only require one insertion / cutting or a significantly reduced number of repeated insertions and cuts. The cutting can also be precisely controlled by the robotic system by operating the first cutting member 37 and the second cutting member 36 together to obtain better and more effective results.

[0066] Figure 8 shown is the star polygon of the first cutting member 37 having eight rotatable blades corresponding to the eight protrusions or corners on the cross-section. Figure 9 shown are multiple exemplary cross-sectional shapes of possible cutting members 137A-F that replace the first cutting member 37. As Figure 9As shown, similar to the first cutting member 37, the cutting members 137A-F may also have a plurality of rotatable blades formed along the longitudinal direction of the cutting member. The cross-sectional shape of the cutting members 137A-F may respectively have one of five, six, seven, eight, nine or ten angular protrusions along the longitudinal direction of the cutting members 137A-F. In some embodiments of the surgical device 20, even-numbered protrusions (e.g., six, eight, ten) are more preferred than odd-numbered protrusions (e.g., five, seven, nine). Similar to the first cutting member 37 described above, the cutting members 137A-F may correspondingly have five, six, seven, eight, nine or ten rotatable blades (straight or curved along the longitudinal direction) for improving the cutting efficiency of the surgical device. In some embodiments, the first cutting member 37 may have a square or rectangular cross-sectional shape with a sharp cutting edge.

[0067] In some embodiments, the cross-sectional shape of the first cutting member 37 may have any polygonal shape other than those described above Figure 8 and Figure 9 in. The polygonal shape may be symmetric or asymmetric. Symmetric polygonal shapes may have, for example, reflection symmetry, linear symmetry, mirror symmetry, bilateral symmetry, point symmetry, rotational symmetry, etc. The polygonal shape may also have asymmetry, for example, asymmetry along any axis or center point.

[0068] Referring again to Figure 8 , in some embodiments, the rings of the extendable element 66 and the support element 67 may extend from the rotatable blade or cutting blade of the first cutting member 37. For example, both the extendable element 66 and the support element 67 may be attached to different parts of the first cutting member 37 without interfering with the operation of the rotatable blade. In some embodiments, the tissue removal assembly 62 may further include a reinforcing ring 68 proximal to the first end of the first cutting member 37. The reinforcing ring 68 is configured to hold the proximal portion of one or more support elements 67. Optionally, the shaft 61 (e.g., the tissue delivery assembly) may be integrated with the tissue removal assembly 62 as described above and further described below.

[0069] Referring again to Figures 5A to 5C , in some embodiments, the tissue removal assembly 62 may have different configurations or arrangements. One or more support elements 67 and one or more extendable elements 66 may be controlled, for example, by the robot controller 90 of the surgical robot system 100 to configure the tissue removal assembly 62 into a plurality of different configurations. Figure 5A A contracted configuration or arrangement of the tissue removal assembly 62 is shown. Figure 5B A partially deployed configuration or arrangement of the tissue removal assembly 62 is shown. Figure 5C A fully deployed configuration or arrangement of the tissue removal assembly 62 is shown (also in Figure 8(shown in). In the fully deployed configuration, the second cutting member 36 can be displaced or moved away from the first cutting member 37, as Figure 8 shown in the side view. The shape and volume of the tissue removal area are at least partially determined by the displacement or distance of the second cutting member 36 from the first cutting member 37. For example, in the fully deployed configuration or arrangement ( Figure 5C ), the shape and volume of the tissue removal area can be significantly larger than those of the contracted configuration ( Figure 5A ) or the partially deployed configuration ( Figure 5B ). Additionally, in Figures 5A to 5C 's embodiment, the second cutting member 36 is configured to deviate from the longitudinal axis of the outer tube 60 and the shaft 61. When the second cutting member 36 rotates, this deviation can generate a flow control vortex effect. As Figure 5B and Figure 5C shown, when the distance of the second cutting member 36 further deviates from the first cutting member 37, the vortex effect can increase or become greater at or around the area of the tissue removal assembly 62. In addition to the vortex effect, the configuration of the threads 35 (e.g., auger) on the shaft 61 and the tip 63 of the outer tube 60 can generate a suction effect to remove tissue and / or fluid from the surgical site. The vortex effect and the suction effect can be generated simultaneously or in coordination with each other to further enhance the efficiency of removing tissue and / or fluid.

[0070] The position of the second cutting member 36 in the (partially or fully) deployed configuration of the tissue removal assembly 62 can be determined by the length and compliance of one or more support elements 67 and one or more extendable elements 66, the attachment position of one or more support elements 67 on the first cutting member 37, and the connection position of one or more support elements 67 and one or more extendable elements 66 on the second cutting member 36. In some embodiments, different configurations or arrangements of the tissue removal assembly 62 can be controlled by the robot controller 90 of the surgical robot system 100. For example, the robot controller 90 can transmit control signals to the drive system and / or other controllers included in the surgical device 20. The drive system and / or other controllers can in turn dynamically adjust or change one or more of the length, compliance, attachment position, connection position associated with the support elements and / or extendable elements. Thus, the robot controller 90 can control the shape and volume of the tissue removal area.

[0071] In some embodiments, one or more support elements 67 and one or more extendable elements 66 may be metal or polymer multifilament cables. Polymer cables such as Kevlar threads or ropes may be bonded, for example using epoxy resin, to the above-mentioned components. The polymer cables may optionally be reinforced by metal rings and / or polymer rings. The metal support elements may be attached to the first cutting member 37 and / or the shaft 61 (e.g., the tissue delivery assembly) by brazing, welding, etc. The polymer support elements may be attached to the first cutting member 37 and / or the shaft 61 by gluing or any other suitable attachment method. The attachment of the annular support element 67 to the first cutting member 37 and / or the shaft 61 may be further fixed and strengthened by a reinforcing ring 68. For example, as Figure 8 shown, the proximal portion of the leading section of the annular support element 67 may be attached at the first attachment location 69, and the proximal portion of the trailing section 71 of the annular support element 67 may be attached at a second attachment location (opposite to location 69 and thus not shown). The second attachment location is directly opposite the first attachment location. In some embodiments, one or more support elements 67 and one or more extendable elements 66 may be made of Kevlar threads or ropes encapsulated in a polyimide tube to provide enhanced or improved pushability and tractability characteristics while maintaining elasticity and the benefits of kink resistance.

[0072] As previously mentioned, the annular support element 67 and the annular extendable element 66 may be joined at the second cutting member 36 by passing through the inner cavity 72 of the second cutting member 36. For example, a portion of the annular support element 67 or the annular extendable element 66 may pass through the inner cavity of the second cutting member 36, as Figure 8 shown. In one variant, depending on the desired level of movement through and / or along the second cutting member 36, the support element 67 and / or the extendable element 66 may be bonded, glued, brazed, welded, etc. to the second cutting member 36. The support element 67 and / or the extendable element 66 may be attached to the second cutting member 36 such that they may be restricted from sliding along the plane of the inner cavity 72, and / or may be restricted from sliding laterally through the plane of the cavity. For example, the support and / or sliding elements held in the cutting inner cavity flaps may be restricted from moving within the plane of the inner cavity, and welded support and / or sliding elements may restrict movement within the plane and in the lateral plane. In some embodiments, the second cutting member 36 may be made of a strength-reinforced metal material such as carbon steel, stainless steel (such as 440C, etc.), tungsten carbide, titanium, steel-iron-nickel alloy, titanium aluminide, nickel-based alloy (inconel), chromium, etc.

[0073] In some embodiments, the position of the second cutting member 36 and the angle of one or more support segments 67 can be determined by adjusting the length of one or more extensible elements 66 outside the second cutting member 37. In some embodiments, the annular support element 67 can be configured to stabilize and maintain the alignment of the cutting element 36 relative to the first cutting member 37.

[0074] Returning to Figure 5A , in the contracted configuration or arrangement of the tissue removal assembly 62, one or more extensible elements 66 can be contracted. Accordingly, the second cutting member 36 can be positioned relatively closer to the first cutting member 37 such that the tissue removal assembly 62 has a low profile (e.g., a profile having a lateral dimension sized substantially similar to the cross-section of the first cutting member 37). In some variations, when one or more extensible elements 66 contract, the second cutting member 36 can be generally or substantially aligned along the central longitudinal axis of the first cutting member 37 of the tissue removal assembly 62. The contraction of one or more extensible elements 66 and the second cutting member 36 toward the first cutting member 37 can cause one or more support elements 67 to fold toward the outer surface of the first cutting member 37. Accordingly, most of the length of one or more support elements 67 overlaps with the longitudinal length of the first cutting member 37. The narrowed profile in the contracted configuration improves the ability of the tissue removal assembly 62 to advance through smaller anatomical regions as well as to advance within cracks and creases in tissue. Additionally, the narrowed profile enables the rotatable blade of the first cutting member 37 to perform critical functions to strip the endplate or tissue even in confined spaces.

[0075] As described above, preoperative imaging and / or intraoperative imaging can be employed to visualize the anatomy of a patient in need of treatment—such as the patient's spine. The surgeon plans the placement of the surgical device 20 (e.g., a discectomy surgical device) or interbody fusion cage within the disc space or pedicle screw relative to the images and / or relative to a 3D model created from the images. The plan includes determining the position of each interbody fusion cage relative to a particular disc space, and / or determining the position of each pedicle screw relative to the particular pedicle bone at which they are targeted (e.g., by identifying the desired positions in the images and / or 3D model). The plan can also include creating or positioning a separate 3D model of the disc space relative to the 3D model of the patient's anatomy. Once the plan is determined, the plan is sent to a surgical robotic system (e.g., Figure 1 and Figure 3 the system 100 shown in

[0076] Referring again to Figure 3 , in some embodiments, the surgical robotic system 100 can be in an operating room or surgical center or laboratory with an imaging device 70 (e.g., as Figure 3used in conjunction with a fluoroscopic C-arm (not shown) to take intraoperative images of a patient's anatomy, instead of or in addition to, any preoperative images (e.g., X-rays, CT scans, or MRI images taken before surgery). Intraoperative images from the imaging device 70 can assist the surgical robot system 100 in determining the actual position / orientation of the surgical device 20, the position / orientation of an intervertebral body fusion implant inserter (not shown), and / or the position / orientation of a screwdriver for a pedicle screw (not shown) relative to the desired position / orientation of the disc space or pedicle of the patient's spine.

[0077] As described above and as Figure 3 shown, when an intervertebral body fusion implant or other implant is placed into an intervertebral disc space, a separate tracking device 12 can be used on each intervertebral disc space to separately track the respective positions of each intervertebral disc space and the surgical device 20, the intervertebral body fusion implant inserter, and / or the screwdriver, drill bit relative to the separate intervertebral disc space or pedicle. For example, the imaging device 70 can generate a DICOM (Digital Imaging and Communications in Medicine) file for the surgical robot system 100. After the surgical robot system 100 processes the DICOM file, the surgical robot system 100 can self-sufficiently use, for example, the surgical device 20 to guide or perform the entire surgery. The surgery can be a discectomy performed at an exact location, an intervertebral body implant performed at a specific location, a pedicle screw trajectory, and / or any other desired operation or procedure. Files in DICOM format are likely to be saved with a DCM or DCM30 (DICOM 3.0) file extension, but some files may have no extension at all. DICOM is both a communication protocol and a file format, which means it can store medical information (such as ultrasound and MRI images) as well as patient information in one file. This format enables all data to be kept together and provides the ability and compatibility to transfer the information between any device or system that supports the DICOM format (such as the surgical robot system 100).

[0078] In some embodiments, the surgical robotic system 100 evaluates the desired positions of the disc space, the intervertebral fusion implant, or the pedicle screw positions. Based on this evaluation, the surgical robotic system 100 generates or defines virtual boundaries (e.g., haptic objects), predetermined tool paths, and / or other autonomous movement instructions. These virtual boundaries, tool paths, and / or movement instructions correspond to the desired positions of the intervertebral fusion implant to control the movement of the robotic arm 50. Thus, the surgical device 20 (e.g., a discectomy surgical device), the intervertebral fusion inserter, and / or a screwdriver for the pedicle screw can be integrated into one device or combined together. The integrated or combined device can be controlled to perform discectomy tissue removal and place the intervertebral fusion implant according to the user's plan. The integrated or combined device can also be controlled to provide the correct trajectory for the pedicle screw. For example, the integrated or combined device can be controlled to ensure that the trajectory of the surgical device 20 during the surgical procedure is aligned with the desired position of the intervertebral fusion implant (e.g., align the trajectories of the discectomy surgical tool and the intervertebral fusion inserter with the desired position of the intervertebral fusion implant).

[0079] Reference Figure 6 , when the surgical robotic system 100 holds the surgical device 20 in the desired position and trajectory, the user can manually manipulate the surgical device 20 to move the surgical device 20, the intervertebral fusion inserter, and / or the screwdriver (or cause them to move) along the line haptic object (e.g., the object forming the virtual boundary) towards the disc space 110 to remove tissue from the disc space 110. In some cases, such as when using the passive robotic arm 50, if the user attempts to move the surgical device 20 in a manner deviating from the line haptic object and the desired trajectory, the surgical robotic system 100 constrains the user's movement of the surgical device 20 by providing haptic feedback to maintain along the desired trajectory. If the user desires to return the robotic arm 50 to the free mode where the movement of the surgical device 20 is unconstrained, the user can pull back the surgical device 20 away from the patient along the line haptic object.

[0080] Again reference Figure 3 , a 3D sensor, an ultrasonic transducer (not shown), and / or a portable MRI imager (not shown) can also be mounted on the robotic arm 50, the locator 11, and / or the dorsal surface of the patient's skin to generate real-time images of the patient's anatomy and the progress of the surgical procedure. The intraoperative images can be used to determine the tissue removal and the intervertebral fusion following the desired planned trajectory. The intraoperative images can also be used to determine whether the surgical device 20, the intervertebral fusion inserter, the intervertebral fusion implant, the screwdriver, and / or the pedicle screw are approaching any critical structures, including nerves and medial or cortical boundaries.

[0081] Figure 7It is a schematic diagram of the lumbar region of the spine 120. The spinal canal 124 is formed by a plurality of vertebrae 121, 122, and 123. The vertebrae 121, 122, and 123 include the anterior vertebral body 127 and the posterior vertebral arch 128. The spinal cord 129 is located within the spinal canal 124. The spinal nerves 130 branch out from both sides of the spinal cord 129 and leave the spinal canal 124 through the intervertebral foramina 126 formed by adjacent vertebrae 104, 106, and 108. The intervertebral foramen 131 is typically bounded by the lower surface of the pedicle 132, a portion of the vertebral body 127, the inferior articular process 133, and the superior articular process 134 of adjacent vertebrae. The transverse processes 126 and the posterior spinous processes 125 of the vertebrae 121, 122, and 123 also project from the vertebral arch 128. The lumbar intervertebral disc 140 is located between the vertebral bodies 127, 135, and 136. The lumbar intervertebral disc (or intervertebral disc) 140 is a fibrocartilage located between the adjacent surfaces of the vertebrae 127, 135, and 136. They form a fibrocartilaginous connection between the vertebral bodies, thereby linking them together.

[0082] Generally speaking, the intervertebral discs 140 account for one-third to one-fourth of the total length of the spine, thereby forming an interposition between adjacent vertebrae from the axis (C1) to the sacrum. There are approximately 23 intervertebral discs in the spine; 6 in the cervical vertebrae, 12 in the thoracic vertebrae, and 5 in the lumbar region. In the lumbar region of the spine, the lumbar intervertebral disc is approximately 7 to 10 mm thick and has a diameter of approximately 4 cm (antero-posterior plane). It consists of a thick outer fibrocartilage ring called the annulus fibrosus 150 that surrounds an internal gel-like center or more gelified core called the nucleus pulposus 110. The nucleus pulposus is clamped by the cartilaginous endplates 160 below and above. Both the annulus fibrosus 150 and the nucleus pulposus 110 are elastic collagen structures, the elasticity of which decreases over time, causing the nucleus pulposus to bulge outwards in the weakened areas of the annulus fibrosus 150 and even extrude through the annulus fibrosus 150. For example, in Figure 4 and Figure 7 once the surgical robotic system 100 ( Figure 3 as shown in Figure 6It depicts accessing a protruding intervertebral disc by manipulating the steering mechanism 38 side, but ipsilateral access can also be used to remove tissue. In other embodiments that can be developed to be coupled to the robotic arm 50, other devices for removing intervertebral disc tissue for discectomy or nucleotomy can include lasers, discectomies, trephines, burrs, rongeurs, files, curettes, and cutting forceps. Many of these devices have a relatively large cross-sectional size, and when inserted into the intervertebral disc, they create an insertion channel that substantially compromises the integrity of the endplate 160 within the disc space 110.

[0083] It should be understood that the systems and methods described herein can be used to remove tissue from the disc space and place interbody fusion implant, cut, drill, or place other implants into a patient. Thus, although tissue removal and interbody fusion implant insertion are always mentioned as an example, the same systems and methods described herein can be used to treat any anatomy of a patient and / or to place any implant into a patient, such as placing in the spine, hip, knee, shoulder, etc. For example, the robotic arm 50 can also be used to drill a guide hole in the pedicle bone and place pedicle screws, rods, or other components for spinal implants, and can be used for cutting, drilling, or other procedures. Different end effectors can also be attached to the robotic arm 50 and the robotic system coupler 55 for other procedures. In some cases, the end effector can also have an articulated arm for other implant insertions, i.e., placing the implant in the desired position. The articulated arm of the end effector can simply be a miniaturized version of the robotic arm 50 controlled in the same manner to place the implant, or can be another mechanism controlled to position the implant. The navigation system 10 can include an optical navigation system having an optically based tracker, but other modalities can be additionally or alternatively employed, such as an ultrasonic navigation system that tracks an object by ultrasonic waves, a radiofrequency navigation system that tracks an object by RF energy, and / or an electromagnetic navigation system that tracks an object by electromagnetic signals. Other types of navigation systems can also be contemplated.

[0084] Several embodiments have been discussed in the foregoing description. However, the embodiments discussed herein are not intended to be exhaustive or to limit the invention to any particular form. The terms used are descriptive rather than restrictive. Given the foregoing teachings, many modifications and variations are possible, and the invention can be practiced in a manner different from that specifically described.

[0085] The foregoing description is provided to enable a person of ordinary skill in the art to practice the various aspects described herein. Those of ordinary skill in the art will readily appreciate various modifications to these aspects, and the general principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the claims, where the elements in the singular form are not intended to mean "one and only one" but rather "one or more" unless specifically stated otherwise. The word "exemplary" as used herein means "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or more advantageous than other aspects. Unless specifically stated otherwise, the term "some" means one or more. Combinations such as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "any combination of A, B, C, or the like" include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, such combinations as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "any combination of A, B, C, or the like" may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combination may include one or more components of A, B, or C. All structural and functional equivalents of the elements of the various aspects described throughout this disclosure that are known or later come to be known to a person of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public, whether or not the disclosure is explicitly recited in the claims. The words "module," "mechanism," "element," "device," etc. are not to be substitutes for the word "means." Thus, an element is not to be construed under 35 U.S.C. § 112(f) unless the element is expressly recited using the phrase "means for."

Claims

1. A tissue removal assembly, comprising: A first cutting member having a plurality of rotatable blades; A second cutting member, One or more support elements slidably or fixedly coupled to the second cutting member, wherein the one or more support elements include an annular support element inserted through an internal portion of the second cutting member; and One or more extendable elements slidably or fixedly coupled to the second cutting member, Wherein the one or more support elements and the one or more extendable elements are extendable and retractable to adjust the position of the second cutting member relative to the first cutting member.

2. The tissue removal assembly according to claim 1, wherein, The first cutting member includes an elongate member, and wherein the plurality of rotatable blades are formed along a longitudinal direction of the elongate member of the first cutting member.

3. The tissue removal assembly according to claim 2, wherein, The plurality of rotatable blades form a plurality of flow control surfaces between the blades, and wherein a cross-section of the first cutting member forms a polygon.

4. The tissue removal assembly according to claim 3, wherein, The cross-section of the first cutting member forms a star polygon including one of five, six, seven, eight, nine, or ten protrusions corresponding to the rotatable blades along a longitudinal direction of the elongate member of the first cutting member.

5. The tissue removal assembly according to claim 1, wherein, The first cutting member and the second cutting member are controlled to operate in coordination with each other.

6. The tissue removal assembly according to claim 1, wherein, The first cutting member and the second cutting member are controlled to operate independently of each other.

7. The tissue removal assembly according to claim 1, wherein, The second cutting member includes one or more rotatable cutting tips.

8. The tissue removal assembly according to claim 1, wherein, The one or more extendable elements include an annular extendable element inserted through an internal portion of the second cutting member.

9. The tissue removal component according to claim 1, wherein, The one or more support elements and the one or more extendable elements are extendable or retractable to configure the tissue removal assembly in a fully deployed configuration, a partially deployed configuration, or a retracted configuration.

10. The tissue removal assembly according to claim 9, wherein, Compared to the fully deployed configuration, the second cutting member is more offset from the first cutting member when the tissue removal assembly is configured in the retracted configuration.

11. The tissue removal assembly according to claim 1, wherein, The one or more support elements and the one or more extendable elements include metal or polymer multifilament cables.

12. A tissue removal assembly, comprising: A first cutting member having a plurality of rotatable blades; A second cutting member, One or more support elements slidably or fixedly coupled to the second cutting member, and One or more extendable elements slidably or fixedly coupled to the second cutting member, wherein the one or more extendable elements include an annular extendable element inserted through an internal portion of the second cutting member, Wherein the one or more support elements and the one or more extendable elements are extendable and retractable to adjust the position of the second cutting member relative to the first cutting member.

13. The tissue removal assembly according to claim 12, wherein, The plurality of rotatable blades form a plurality of flow control surfaces between the blades, and wherein a cross-section of the first cutting member forms a polygon.

14. The tissue removal assembly according to claim 13, wherein, The cross-section of the first cutting member forms a star-shaped polygon, and the star-shaped polygon includes one of five, six, seven, eight, nine, or ten protrusions corresponding to rotatable blades along the longitudinal direction of the elongated member of the first cutting member.

15. The tissue removal assembly according to claim 12, wherein, The first cutting member and the second cutting member are controlled to operate in coordination with each other or independently of each other.

16. The tissue removal assembly according to claim 12, wherein, The second cutting member includes one or more rotatable cutting tips.

17. The tissue removal component according to claim 12, wherein, The one or more support elements include an annular support element inserted through an internal portion of the second cutting member.

18. The tissue removal assembly according to claim 12, wherein, The one or more support elements and the one or more extendable elements are extendable or retractable to configure the tissue removal assembly into a fully deployed configuration, a partially deployed configuration, or a retracted configuration.

19. The tissue removal assembly according to claim 18, wherein, Compared with the fully deployed configuration, the second cutting member is more offset from the first cutting member when the tissue removal assembly is configured in the retracted configuration.

20. A surgical robot system, comprising: A robot controller; A robotic arm controlled by the robot controller; A surgical device coupled to the robotic arm, wherein the surgical device includes a tissue removal assembly, and the tissue removal assembly includes: A first cutting member having a plurality of rotatable blades, A second cutting member, One or more support elements slidably or fixedly coupled to the second cutting member, wherein the one or more support elements include an annular support element inserted through an internal portion of the second cutting member; and One or more extendable elements slidably or fixedly coupled to the second cutting member, wherein the one or more support elements and the one or more extendable elements are extendable and retractable to adjust the position of the second cutting member relative to the first cutting member.

Images