Apparatus for drive-specific anti-roll-back

Abstract

This invention discloses a dedicated anti-reverse mechanism for a drive comprising a screw and a body. A first drive is used to engage and disengage the screw from the body, and a second drive is used solely to adjust the position of the screw within the receiving body. The body includes a cavity for receiving the head of the screw, wherein the cavity has an inwardly projecting flange. The screw includes an upper socket and a lower socket, the screw having a channel extending from the lower socket through the head and a locking body disposed within the channel. Engagement with the first drive allows movement of the locking body, enabling the fastener to be inserted into and removed from the body. Engagement with the second drive displaces the locking body, causing it to interfere with the flange, preventing the screw fastener from being removed from the body by the second drive.

Description

Technical Field

[0001] This disclosure relates generally to surgical instruments, systems, and methods, and more specifically to instruments, systems, and methods including drive-specific anti-reverse features that selectively enable different actuators to operate components. Such instruments, systems, and methods can be used in a variety of surgical procedures, such as orthopedic or neurosurgical procedures, including spinal fusion surgery. Background Technology

[0002] Surgical procedures are used to treat and manage a wide range of diseases, conditions, and injuries. Surgical procedures often require access to internal tissues through open or minimally invasive methods. The term "minimally invasive" refers to all types of minimally invasive surgery, including endoscopic, laparoscopic, arthroscopic, natural orifice endoscopic, and transoral endoscopic procedures. Compared to traditional open surgery, minimally invasive surgery offers numerous advantages, including reduced trauma, faster recovery, lower risk of infection, and less scarring.

[0003] Whether minimally invasive or not, there are various surgical procedures in which it may be desirable to create a working channel within the patient's body to provide access to surgical sites within the patient's body. One such example is orthopedic or neurosurgical procedures, including, for example, spinal fusion surgery, where it may be desirable to create a working channel through the patient's tissues to access their vertebrae and / or the intervertebral discs located between adjacent vertebrae.

[0004] Various methods are known for providing such a working passage, including devices anchored to a surgical table on which the patient is positioned, devices penetrating tissue without anchoring to any other structure, or devices anchored to multiple anchors implanted in the patient's bone. In such arrangements, the devices may not be properly supported, may move undesirably relative to the patient in the event of movement of the patient relative to the operating table or some other external structure, or may hinder certain aspects of the surgeon's or other user's performance of the procedure.

[0005] For example, in spinal surgery involving the operation on the intervertebral disc between adjacent vertebrae, access to the disc space can be difficult. The advent of modular pedicle screws allows for the implantation of pedicle anchors before disc manipulation. Therefore, a retractor assembly is used to keep the surgical access site open for pedicle screw insertion and subsequent manipulation. However, retractor assemblies typically require complex articulations of various retractor arms and blades to achieve an optimized access site. Therefore, retractor devices often utilize multi-axis joints that can be selectively loosened and tightened during surgery; however, retractor device components including multi-axis joints require disassembly and sterilization before and after use.

[0006] Therefore, there is a need for improved devices, systems, and methods that ensure the safe and reliable selection of locking mechanisms between instrument components to prevent accidental disassembly during surgical procedures, while also allowing for selective articulation and movement between certain components. For example, there is a need for improved fastener assemblies to allow for the secure assembly and safe adjustment of multi-component devices during surgical procedures without the risk of accidental disassembly. Summary of the Invention

[0007] This document discloses surgical instruments, systems, and methods that provide anti-retraction screws for locking components of multi-axis restraint and surgical retractor assemblies. For example, embodiments described herein provide a fastener and threaded housing assembly that can be used to adjust the position of, for example, multiple balls in a socket of a multi-axis joint using two different actuators, wherein a first actuator can be used to completely (e.g., retract) remove the fastener from the threaded housing, and a second actuator can be used solely to adjust the position of the fastener within the housing. Embodiments described herein offer numerous advantages over prior methods. These may include, for example, the ability to prevent accidental detachment of the fastener from the housing during surgery when adjusting the fastener using a specific actuator trip, the ability to insert and remove the fastener into the housing using the second actuator before or after surgery, so as to sterilize, for example, the fastener and housing separately.

[0008] The anti-reverse mechanism includes a body configured to receive a fastener, the body defining a cavity configured to receive the head of the fastener when the fastener is disposed in the body, the cavity having an inwardly extending flange defining a proximal opening of the cavity; a fastener having a threaded portion and a head portion; and a locking body disposed in each of at least one radially extending channels of a screw. The head portion has an upper recess configured to abut with a driver for adjusting the position of the fastener within the body; and at least one channel extending radially from a lower recess, the at least one channel being sized and shaped to allow translation of the locking body through the channel. The anti-reverse mechanism has a first configuration when the head portion of the fastener is engaged by a first driver, and a second configuration when the head portion of the screw is engaged by a second driver. In the first configuration, the engagement of the drive portion of the first actuator with the upper recess of the head portion allows the locking body to move radially inward within the channel, enabling the fastener to be inserted distally into the body and removed proximally without interference between the locking body and the flange of the cavity. In the second configuration, when the fastener is disposed in the body such that at least one radially extending channel is disposed distal to the flange of the cavity, the engagement of the drive portion of the second actuator with the upper recess includes the engagement of the distal end portion of the second actuator with the lower recess of the head portion. This engagement causes the locking body to shift radially outward, such that when the fastener is advanced proximally by the second actuator, the locking body interferes with the flange of the channel, preventing the fastener from being removed from the body by the second actuator.

[0009] In some cases, the locking body is a ball bearing. The cavity may define a length below the flange, the length of which defines the maximum possible adjustment distance of the fastener in the body of the second configuration. The cavity may define a cylindrical inner wall, and wherein the flange is a radial flange. In some cases, the inner wall of the cavity defines a width greater than the diameter of the head portion of the fastener plus twice the extension distance of the locking body in the second configuration from the head portion.

[0010] A radially extending channel is configured to hold the locking body in the radially extending direction. A lower bearing recess may define a cylindrical inner wall. An upper bearing recess may define a shape configured to mate with the shape of the drive portions of the first and second actuators, and to allow torque to be delivered from the drive portions to the fastener for adjusting the position of the fastener within the body. The body may include a threaded portion configured to receive the threaded portion of the fastener.

[0011] In some cases, in the first configuration, the maximum engagement position between the drive portion of the first driver and the upper bearing socket of the head portion is defined by the contact between the drive shaft of the first driver and the upper bearing socket.

[0012] In some cases, in the second configuration, the maximum engagement position of the distal end portion of the second actuator is defined by the contact between the distal end portion and the bottom of the lower bearing recess.

[0013] In some cases, in at least one of the first or second configurations, the maximum engagement position of the drive portion is defined by the contact between the drive feature portion of the drive portion and the end of the corresponding drive feature portion in the upper bearing socket.

[0014] Another example of this disclosure is a surgical instrument having a retractor body configured to be coupled to an implantable anchor; a first tissue manipulation device coupled to the retractor body and capable of multi-axis movement relative to the retractor body; and a second tissue manipulation device coupled to the retractor body and capable of multi-axis movement relative to the retractor body. Each of the first and second tissue manipulation devices is coupled to the retractor body via a multi-axis joint, and each joint includes a screw to selectively lock the multi-axis joint against movement, and wherein each manipulation device and screw includes an anti-retraction mechanism according to an example of this disclosure, wherein the manipulated implant includes the body of the anti-retraction mechanism, and the screw includes a fastener.

[0015] In some cases, the first and second organizational manipulation devices are positioned opposite each other, allowing them to move toward or away from each other.

[0016] The device may include a lock that is coupled to the body and configured to mate with the anchor extension to selectively lock the position of the body relative to the anchor extension.

[0017] In some cases, each of the first and second organizational manipulation devices is connected to the body via a ball joint. In some cases, each ball joint includes an expansion member configured to selectively lock the ball joint to resist movement.

[0018] Another example of this disclosure is an anti-reverse system having a body configured to receive a fastener, the body defining a cavity configured to receive the head of the fastener when the fastener is disposed in the body, the cavity defining an inwardly extending flange at a proximal position of the cavity; a fastener having a threaded portion and a head portion, the head portion having an upper socket, a lower socket and at least one channel, the upper socket being configured to abut with a driver for adjusting the position of the fastener within the body, the at least one channel extending radially from the lower socket and being sized and shaped to allow translation of the locking body through the channel. The system also includes a locking body disposed in each of at least one radially extending channel of the screw; and a locking actuator having a distal end region sized and shaped to engage both an upper and lower bearing socket, the distal end region having a driving portion and a locking portion located distal to the driving portion, wherein the driving portion is configured to abut the upper bearing socket for delivering torque to the fastener to adjust the position of the fastener in the body, and wherein the locking portion is configured to be disposed in the lower bearing socket when the driving portion abuts the upper bearing socket, and its size and shape are set to radially displace the locking body outward to prevent the locking body in the fastener from moving proximally beyond the flange. A standard actuator with a distal end has a driving portion but does not have a locking portion sized and shaped to allow radial outward movement of the locking body; this standard actuator is capable of delivering torque to the upper bearing socket to adjust the position of the fastener proximally and distally without creating interference between the locking body and the flange.

[0019] In some cases, the body is a first body, and the system also includes a second body configured to be coupled to an implantable anchor, wherein the first body defines at least a portion of a manipulator configured to be coupled to the second body and capable of multi-axis movement relative to the second body, wherein the tissue manipulator is coupled to the second body via a multi-axis joint, and wherein the position of fasteners in the first body selectively locks the multi-axis joint to resist movement.

[0020] Another example of this disclosure is a method for assembling and adjusting the position of a fastener in a locking mechanism, the method comprising: inserting a fastener into a body of the locking mechanism; engaging a first actuator to the fastener and using the first actuator to distally screw the fastener into engagement with the body, such that a locking body disposed in a radially extending channel of the fastener is positioned distal to an inwardly extending flange in a cavity of the body; engaging a second actuator to the fastener, wherein the second actuator causes radially outward displacement of the locking body, such that the locking body interferes with the flange of the channel to prevent proximal movement of the fastener beyond a position where the locking body abuts the flange; adjusting the position of the fastener in the body using the second actuator by screwing the fastener between a maximum proximal position and a maximum distal position defined by interference between the locking body and the flange. In some cases, the locking body is a ball bearing.

[0021] In some cases, the body includes a collet disposed in a socket, and inserting a fastener into the body includes connecting the distal end of the fastener to an expansion member disposed in the collet, such that adjusting the position of the fastener in the body causes the collet in the socket to expand and contract and adjusts the level of frictional engagement between the collet and the socket.

[0022] In some cases, the body is a first body that defines at least a portion of the manipulator, and the socket is part of a second body configured to be coupled to an implantable anchor, and the method further includes coupling a collet to the socket after inserting a fastener into the first body using a first actuator, the collet and the socket defining a multi-axis joint, and wherein adjusting the position of the fastener in the body using a second actuator includes selectively locking the multi-axis joint to resist movement.

[0023] Any of the above features or variations can be applied in a variety of different combinations to any particular aspect or embodiment of this disclosure. No specific combination is explicitly described merely to avoid redundancy within the scope of this invention. Attached Figure Description

[0024] This disclosure will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1 This is a diagram illustrating one embodiment of a surgical instrument assembly based on the teachings provided herein;

[0026] Figure 2 yes Figure 1 Detailed diagram of the retractor component;

[0027] Figure 3 yes Figure 1 Component breakdown diagram;

[0028] Figure 4 yes Figure 2 Exploded view of the retractor;

[0029] Figure 5 yes Figure 2 A detailed view of the partially transparent retractor;

[0030] Figure 6 yes Figure 2 A detailed, transparent view of the bottom portion of the retractor;

[0031] Figure 7 This is a front perspective view of another embodiment of a surgical instrument assembly based on the teachings provided herein;

[0032] Figure 8A yes Figure 7 A perspective view of the actuator components;

[0033] Figure 8B yes Figure 8A Alternate view of the actuator;

[0034] Figure 9 yes Figure 8A A partially transparent perspective view of the actuator;

[0035] Figure 10A yes Figure 7 A perspective view of the distal end of the actuator tip of the component;

[0036] Figure 10B Is with Figure 7 A perspective view of the tip of an alternative distal end actuator used in conjunction with the components of the actuator.

[0037] Figure 11A Is with Figure 2 A partial transparent view of an implementation of a drive-specific anti-reverse assembly used in conjunction with the locking mechanism of the multi-axis connector of the retractor;

[0038] Figure 11B yes Figure 11A A cross-sectional view of the component, showing the screw in a proximal position;

[0039] Figure 11C yes Figure 11A A partially transparent view of the component, showing the screw in the far-side position.

[0040] Figure 11D yes Figure 11C A cross-sectional view of the component;

[0041] Figure 12A Is with Figure 10B The driver tip used together Figures 11A to 11D A partially transparent view of the driver-specific anti-rollback component;

[0042] Figure 12B yes Figure 12A A cross-sectional view of the component, showing the screw in the distal position with the partially inserted anti-return drive tip;

[0043] Figure 12C yes Figure 12A A partially transparent view of the components, showing the fully inserted anti-reverse drive tip;

[0044] Figure 12D yes Figure 12C A cross-sectional view of the component;

[0045] Figure 12E yes Figure 12A A partially transparent view of the components, showing the fully inserted anti-retraction drive tip and the fully retracted screw, and the anti-retraction mechanism engaging the inner flange of the body;

[0046] Figure 12F yes Figure 12E A cross-sectional view of the component;

[0047] Figure 12G yes Figure 12A A cross-sectional view of the components, showing the screw in a proximal position with the partially inserted anti-return drive tip;

[0048] Figure 12H yes Figure 12G A cross-sectional view of the component;

[0049] Figure 13A yes Figures 11A to 12H A top cross-sectional view of a dedicated anti-reverse drive assembly, wherein the tip of the anti-reverse drive is positioned within the screw socket;

[0050] Figure 13B yes Figure 13A A top cross-sectional view of the component, wherein the standard driver tip is positioned within the screw socket; and

[0051] Figure 14 yes Figures 11A to 12H A photograph of an implementation of a dedicated anti-rollback component for a driver. Detailed Implementation

[0052] Certain exemplary embodiments will now be described to provide a comprehensive understanding of the principles of the structure, function, manufacture, and use of the apparatuses and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the apparatuses and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments, and that the scope of this disclosure is defined only by the claims. Features shown or described in conjunction with one exemplary embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be included within the scope of this disclosure.

[0053] Furthermore, the use of linear or circular dimensions in the description of the disclosed devices and methods is not intended to limit the types of shapes that can be used in conjunction with such devices and methods. Equivalents to such linear and circular dimensions can be determined for any geometry. Additionally, in this disclosure, components with similar designations in the embodiments generally have similar characteristics. Moreover, the size and shape of the device and its components may depend at least on the anatomy of the subject in which the device will be used, the size and shape of the components to be used with the device, and the method and procedure in which the device will be used.

[0054] Figures 1 to 6 An exemplary surgical instrument assembly 100 is shown in accordance with the teachings provided herein. Assembly 100 can be used in a variety of surgical procedures, including spinal surgeries such as microsurgical osteotomy, spinal decompression, spinal fusion, etc. Typically, assembly 100 may include a support device 102 coupled to an implanted anchor 104 (such as a pedicle screw or other bone screw). Assembly 100 may also include a retractor 106 coupled to the support device 102. Other components not shown herein may be included or coupled to assembly 100. Such components may include, for example, any of a variety of camera or visualization systems, and any of a variety of other surgical instruments.

[0055] use Figures 1 to 6 An exemplary method of component 100 may include any one or more of the following steps performed in any of a variety of sequences: a) making an incision in the patient's skin; b) inserting an implantable anchor, such as a pedicle screw or other bone screw, through the incision via the skin; c) coupling a support device 102 to the implanted anchor (e.g., a pedicle screw anchor); d) coupling a tissue retractor to the device; e) providing medial and lateral retraction of the tissue surrounding the incision; f) coupling an optical visualization device to the tissue retractor and / or the device; g) removing a portion of the superior articular process and / or performing microsurgical decompression; h) removing intervertebral disc material, including removing cartilage material from the vertebral endplate; i) inserting an intervertebral body device; and j) deploying a stabilizing mechanism to stabilize the intervertebral segment.

[0056] The retractor assembly 106, combined with the support device or anchor extension 102 and the implanted anchor 104, can be used, for example, to widen incisions formed in the patient's skin and tissues for better access to the surgical site. By another example, in some embodiments, these components can form an assembly anchored to a single implanted screw or anchor and provide medial and lateral tissue retraction to increase accessibility to a variety of surgical procedures. Medial lateral retraction of the skin and underlying tissue around the incision provides a wider opening and working channel between the tissue manipulators to access the patient's spine or intervertebral space. In some embodiments, the working channel can extend to encompass adjacent anchors implanted in adjacent vertebrae. Once the tissue of the incision wall is retracted to form the working channel, any of a variety of surgical procedures can be performed by introducing one or more instruments through the working channel defined by the tissue manipulators of the retractor assembly. For example, procedures in the intervertebral disc space, such as disc replacement, discectomy, endplate preparation, fusion cage insertion, bone graft delivery, etc., can be performed by passing an instrument or implant through the working channel.

[0057] return Figures 1 to 6 , Figure 1 One embodiment of a surgical instrument assembly 100 is shown, which includes a support device 102 coupled to an implantable anchor 104 and a tissue retractor 106. Further details regarding embodiments of the assembly 100 can be found in U.S. Patent Application 16 / 139,409 entitled “PATIENT-MOUNTED SURGICAL SUPPORT” and U.S. Patent Application 16 / 139,434 entitled “PATIENT-MOUNTED SURGICAL RETRACTOR”, both filed September 24, 2018. Further details regarding embodiments of the implantable anchor 104 can be found in U.S. Patent Application 15 / 208,872 entitled “BONE ANCHOR ASSEMBLIES AND RELATED INSTRUMENTATION”, filed July 13, 2016. Additionally, details regarding certain embodiments of the retractor that can be used in the surgical assembly 100 can be found below and in U.S. Patent 7,491,168. The entire content of each of these references is incorporated into this paper by way of citation.

[0058] Generally, the support device may include an elongated body 108 having a laterally extending fork formed at its distal end, which can engage with a narrow neck of an anchor 104. The fork may include opposing projections extending laterally from the distal portion of the elongated body and defining a U-shaped or open recess sized to receive a portion of the implantable anchor 104. For example, the projection may be configured to fit around a proximal portion of a bone anchor, which may be part of a modular uniaxial or multiaxial pedicle screw. Such an anchor may include a generally cylindrical distal shank portion having threads for tapping into the bone, and a narrow neck and a wider proximal head proximal to the shank portion. The proximal head may be generally spherical or hemispherical in shape and may be configured to engage with the receiver head before or after implantation into the patient's bone. The elongated body may also include a lock configured to apply a drag force to the head of the anchor to control multi-axis movement of the device 102 relative to the anchor 104. Figure 3 As shown, the lock may include a lock body 302 coupled to an elongated body 108 and capable of translational relative to it along a longitudinal axis 304 of the elongated body. The lock body 302 may have a generally elongated shape to facilitate coupling with and translational or sliding along or relative to the elongated body 108. The lock may be actuated by a locking screw 305 that causes distal translation of the lock body 302 as the screw is further screwed into the elongated body 108. The lock body 302 may also include a laterally extending annular protrusion 306 at its distal end, which may be configured to contact and apply a drag force thereon to the proximal head of the anchor 104. The annular protrusion 306 may define an interior cavity to maintain access to a drive feature formed on the proximal end of the head of the anchor 104. The combination of the inner cavity, the lateral extension of the protrusion 306, and the fork formed at the distal end of the elongated body 108 allows for the orientation of the instrument 100 such that the longitudinal axis of the instrument is laterally offset from or non-axial with the longitudinal axis of the anchor 104. Even when the instrument 100 is attached to the anchor 104, this configuration allows the actuator or other instruments to enter the drive features of the anchor. This enables flexible implantation of the anchor before and after the instrument 100 is attached to the anchor 104.

[0059] return Figure 2A more detailed illustration of one embodiment of the tissue retractor 106 is provided. The retractor 106 may include a body 202 configured to be coupled to a support device or anchoring extension 102. A first tissue manipulation device 204 and a second tissue manipulation device 206 may be coupled to the body 202, respectively, via, for example, rigid arms 208, 210. Each of the first tissue manipulation device 204 and the second tissue manipulation device 206 is capable of multi-axis movement relative to the body via multi-axis joints 212, 214 (such as ball joints). Such joints allow the tissue manipulation devices 204, 206 to move relative to each other in various ways. For example, the devices 204, 206 may be about an axis extending parallel to the longitudinal axis of the support device 102 (e.g., parallel to...). Figure 3 The devices 204 and 206 may also pivot about or away from each other about a transverse or oblique axis, such as axis 304. For example, the devices 204 and 206 may be oblique relative to each other, wherein the distal ends of the devices move about or away from each other by a greater amount than the proximal ends of the devices. In some embodiments, oblique movement may include moving the distal ends of the devices away from each other while the proximal ends of the devices move about or remain still, such that the distance between the proximal ends of the devices remains constant. Furthermore, each multi-axis joint 212 and 214 may include locks 216 and 218 that can be used to selectively lock the position of the associated tissue manipulation device 204 or 206 or apply a dragging force to inhibit movement in the absence of at least a threshold level of force.

[0060] As described above, the tissue retractor 106 can be configured to be coupled to a support device or anchor extension 102 and can be configured to slide along the length of such device to adjust the height of the retractor relative to the implanted anchor 104. Figure 2 As shown, the body 202 of the retractor may include a closed or partially open cavity or recess 220 configured to receive a portion of the support device 102, such as an elongated, generally cylindrical body 108 (see Figure 108). Figure 1 The retractor 106 may also include features that selectively lock the position of the retractor relative to the support device 102, such as a spring-biased protrusion or pawl 222, which may engage a ratchet rack or other series of recesses or other surface features formed on the elongated body 108 of the support device. Furthermore, in some embodiments, the locking feature 222 may be configured to prevent not only movement along the length of the support device 102 but also rotation about it. An actuator 224 (such as the sliding or translating member shown) may be included to allow a user to easily withdraw the protrusion 222 against the biasing force of a spring or other biasing element disposed within the body 202 of the retractor 106.

[0061] In addition to adjusting the position of the retractor 106 along the length of the support device 102, the length of each of the tissue manipulation devices 204, 206 can also be adjusted. For example, in some embodiments, the tissue manipulation devices 204, 206 may each include extensions 226, 228 that can be configured to translate relative to the tissue manipulation devices 204, 206. Translation of the extensions 226, 228 proximally or distally relative to the associated devices 204, 206 can change the overall length of the devices, and, for example, allow the extensions to penetrate deeper into the tissue even if the retractor 106 is mounted at a higher height above the patient's skin surface along a more proximal portion of the elongated body 108 of the support device.

[0062] Figure 3 A partially exploded view is shown illustrating how a retractor 106 can be coupled to a support device 102 by sliding the retractor downwards or distally over a proximal portion of the support device. For example, a recess or cavity 220 of the retractor 106 can be aligned with the generally cylindrical elongated body 108 of the support device, and the retractor can be advanced downwards or distally along axis 304. While advancing the retractor relative to the support device, the user can manually retract a spring-biased pawl or protrusion 222 using a sliding lever 224 to allow free movement of the retractor relative to the support device. When the desired position is reached, the user can release lever 224, causing the protrusion 222 to engage with a complementary recess or other feature formed on the elongated body 108 to maintain the relative positioning of the retractor and the support device. In other embodiments, complementary features formed on the elongated body 108 and the protrusion 222 can be configured as a biasing ratchet, wherein, for example, distal advance of the retractor can be achieved without actuating the lever 224, but proximal withdrawal of the retractor 106 relative to the device 102 requires actuating the lever 224 to withdraw the biasing protrusion 222.

[0063] Figures 4 to 6The retractor 106 is shown in various exploded and partially transparent views to better explain the interaction of its various components. For example, multi-axis joints 212, 214 can be seen in more detail. Each multi-axis joint 212, 214 may include a socket 402, 404 formed in the body 202 of the retractor 106. Each of the arms 208, 210 coupled to the tissue manipulation instruments 204, 206 may have a generally spherical proximal end 406, 408 (e.g., a chuck) including one or more release slots formed therein, such that portions of the proximal end (e.g., a flap 428) are deformable relative to other portions of the proximal end. Locks 216, 218 are coupled to each arm 208, 210 via a mating engagement between threads 410, 412 formed on the lock and threads 414, 416 formed on the inner surface of through-holes in the arms 208, 210. Furthermore, an expansion member 420 may be disposed at the distal end of each lock 216, 218 and arranged within the spherical proximal end 408, such that adjustment of the position of the lock 218 by movement along the thread 412 allows the expansion member 420 to move distally within the spherical proximal end 408, thereby pushing the flaps 428 outward, or the expansion member 420 may retract proximally, such that it is more situated within the curved inner surface of the flaps 408 and does not push them outward. The locking assembly 499 may include a portion of the lock 218 and the arm 210 to which the lock 218 is operatively coupled.

[0064] During assembly, such as Figure 5 and Figure 6As shown, expansion members 418, 420 can be disposed in an unlocked (e.g., retracted) position within generally spherical proximal ends 406, 408, allowing expansion members 418, 420 to be disposed within one of the recesses 402, 404 of the body 202. To lock the spherical proximal ends 406, 408 within and relative to one of the recesses 402, 404, locks 216, 218 can be rotated relative to arms 208, 210, further advancing expansion member 420 into the spherical proximal end 408 due to the threaded connection between arms 208, 210 and locks 216, 218. Advancing locks 216, 218 into the spherical proximal end 408 results in expansion members 418, 420 forming at the distal end of each lock, causing the flap 428 to expand radially outward within the recesses 402, 404. As the lobes 428 of the spherical proximal ends 406, 408 expand radially, they are pushed into contact with the sidewalls of the sockets 402, 404. This can result in an increase in friction between the sockets 402, 404 and the spherical proximal ends 406, 408 of the arms 208, 210. Furthermore, after the locks 216, 218 are fully advanced, the expansion members 418, 420, resisting the force of the lobes 428, can effectively lock the spherical proximal ends 406, 408 in a given position, thereby preventing any movement of the arms 208, 210 or the tissue manipulation devices 204, 206 attached to the arms.

[0065] Figure 7 An alternative embodiment of a surgical instrument assembly 1000 is shown, which includes a support device 1002 coupled to an implantable anchor 104 and a tissue retraction assembly 1006. An embodiment of an actuator 1008 for actuating locks 1010, 1012 is also shown, which selectively allows or prevents multi-axis movement of opposing tissue manipulation instruments 1014, 1016 relative to the body 1018 of the retraction assembly 1006.

[0066] Figures 8A to 9The actuator 1008 is shown in more detail. In some embodiments, the actuator 1008 may include a housing 1802 disposed around a drive shaft 1804, which is coupled to a handle 1806 at its proximal end. The distal end 1812 of the drive shaft 1804 may be configured to abut against the proximal ends of locks 1010, 1012 of the tissue retractor assembly 1006 to apply an actuating torque thereto. The actuator 1008 may also include a stabilizing shaft 1810 coaxially disposed around the drive shaft 1804 and coupled to the housing 1802 and the interface 1808. The interface 1808 may include opposing slots or cutouts 1814, 1816 that, when the interface is disposed on one of the locks 1010, 1012, may receive a portion of one of the arms 1302, 1304 such that the distal end 1812 of the drive shaft 1804 engages the lock. The user can then resist any tendency of the retractor assembly 1006 to rotate or otherwise move in response to turning the handle 1806 by keeping the housing 1802 stable. More specifically, the rigid, non-rotational connection between the housing 1802, the stabilizing shaft 1810, and the interface 1808, combined with the interface 1808 which cannot rotate relative to the arms 1302, 1304 due to the slots 1814, 1816, provides effective stability when the user holds the base 1802 while turning the handle 1806.

[0067] One problem with the aforementioned type of instrument is that the user may unintentionally retract the screw 419 of locks 216, 218 too far during surgery. This can cause the screw 419 to disengage from the threads 414, 416 of the tissue manipulation arm 208, 210. To prevent this, embodiments of this disclosure provide a mechanism for preventing the screw 419 of locks 216, 218 (also referred to as a multi-ball fastening screw) from being unintentionally removed during surgery. However, since the screw 419 also needs to be disassembled for cleaning and initial assembly, the screw 419 needs to be able to be selectively removed beyond its stop. Therefore, an anti-retraction mechanism that allows selective removal of the screw 419 beyond its stop is provided and described herein. This mechanism can be added to locking assembly 499 where retraction of the screw 419 is required to allow the flap 428 of the ball proximal end 408 to collapse and insert into the socket 404; however, retraction completely disconnects the screw 419 from the threads 416 and / or expansion member 420. This creates the need for the stop to notify the user when the screw 419 is fully retracted and / or to prevent the screw 419 from unexpectedly disengaging from the expansion member 420, while still allowing the adjustment screw 419 to be able to adjust the locking assembly 499.

[0068] One purpose of the anti-retraction mechanism is to allow anti-retraction to occur without permanently capturing the screw or lock 218, as permanent capture of the screw of lock 218 is undesirable due to the challenges posed by component sterilization. For example, component 499 may require complete disassembly after use and complete sterilization of each component, which requires both removing screw 419 from thread 416 and removing expansion member 420 from screw 419. If more conventionally captured screws are used to prevent unintentional retraction, complete disassembly would be impossible and thorough cleaning and sterilization could be difficult. Therefore, this disclosure provides a mechanism for selective anti-retraction based on the actuator used by the user, which allows selective anti-retraction during operation but allows complete disassembly for cleaning and sterilization. As explained in more detail below, locking assembly 499 may include a fastener (e.g., screw 419) and a body (e.g., the portion of arm 210 that receives screw 419), which together operate to provide an anti-retraction mechanism that allows screw 419 to be assembled or disassembled or adjusted with a first actuator and adjusted with a second actuator, wherein the second actuator cannot be used to disassemble or retract screw 419 from arm 210.

[0069] Figure 10A This is a perspective view of one embodiment of the distal end 1812 driver tip 1813, which can be used for example... Figure 7 The actuator 1008 is a component of the device. Figure 10A The arrangement can also be referred to as a standard actuator. As explained in more detail below, the standard actuator 1812 can be used to fully adjust the lock 218 or other fasteners in the locking assembly 499 (or as... Figures 11A to 14 Positioning of the locking component 599 shown, including the initial assembly or subsequent disassembly of the locking component 499. Figure 10B Is with Figure 7 A perspective view of the alternative distal end driver tip used in conjunction with the actuator components. Figure 10B An anti-reverse actuator 1901 is shown, which includes a distal end 1912 having two separate regions: a proximal actuator tip 1913 and a distal interference element 1914 extending between the actuator tip 1913 and the termination of the distal end 1912. In operation, and as discussed in more detail below, the anti-reverse actuator 1901, together with locking components 499, 599, prevents the fastener or lock 218 from being disassembled from or fully retracted from the body 210.

[0070] exist Figure 10A and Figure 10B In the illustration, the actuator tips 1813 and 1913 are shown as having a six-lobed actuator feature, which is one of many common actuator features and is shown only as an example. Many different actuator features can be used with the examples disclosed herein.

[0071] Figures 11A to 11D Is with Figure 2 Partial transparent and cross-sectional view of the drive-specific anti-reverse assembly 599 used with screws 419 and locks 218 for the multi-axis joint of the retractor. Figure 11A It is a partially transparent view, and Figure 11B This is a cross-sectional view, both showing the actuator-specific anti-reverse assembly 599, where a standard actuator 1812 is disposed in the socket 2218 of a screw 519 disposed in a body 2210. The body 2210 can be, for example, a portion of arm 210 receiving the screw 519. The screw 519 may have a threaded portion that screws into a corresponding threaded portion of the body 2210. However, in some cases, the body 2210 and the portion with the corresponding thread 416 can be separate components, and in other examples, the screw 519 and the body 2210 can be connected to components other than threads, such as pin and channel systems or other components known in the art. Continuing, the body 2210 defines a cavity 2215 for receiving the head portion 2218 or socket of the screw 519. The cavity 2215 includes an inwardly extending flange 2211 or projection that is located in the head portion 2218 of the anti-reverse actuator (e.g., the anti-reverse actuator is disposed in the head portion 2218). Figures 12A to 12H (As shown) is used as a stop.

[0072] return Figure 11A and Figure 11B The head portion of screw 419 defines an upper bearing recess 2220 and a lower bearing recess 2250, wherein the drive tip 1813 is only capable of engaging the upper bearing recess 2220. The head portion 2218 also includes one or more channels 2219 extending radially from the lower bearing recess 2250. Each channel 2219 accommodates a locking body, such as a ball bearing 2240 as shown. In operation, the anti-reverse assembly 599 allows the standard drive 1812 to be fully inserted into and removed from the body 2210 because the ball bearing 2240 disposed in the channel 2219 does not interfere with the flange 2211, due to its ability to be radially deflected inward by the flange 2211 at least partially into the lower bearing recess 2250, as shown. Therefore, Figure 11A and Figure 11B An anti-reverse assembly 599 with a standard driver 1812 in the "up" position is shown, wherein the convex six-lobed feature of the driver tip 1813 is located at the bottom of the concave lobe in the upper bearing socket 2220, and the ball bearing 2240 moves freely inward and allows the screw 519 to be removed from the body 2210. Figure 11C and Figure 11DAn anti-reverse assembly 599 with a standard actuator 1812 in the "downward" position is shown. Additionally, distal advance of the screw 419 is limited by the interaction between the distally facing surface of the head portion 2218 and the proximal facing surface of the cavity, as... Figure 11D As shown.

[0073] Figures 12A to 12H Is with Figure 10B The anti-rollback driver 1901 is used together Figures 11A to 11D Partial transparent and cross-sectional view of the driver-specific anti-backflow component 599. Figure 12A and Figure 12B The distal end 1912 of the anti-reverse actuator 1901 is shown inserted into the head portion 2218 of the screw, with the screw 519 in the "downward" position, and an interference element 1914 disposed in the upper bearing recess 2220. In this position, the interference element 1914 cannot engage the upper bearing recess 2220 to drive the screw 519 because the interference element 1914 does not have an engagement feature. Additionally, the ball bearing 2240 is not restricted by any object disposed in the lower bearing recess 2250 and moves freely.

[0074] exist Figure 12C and Figure 12D The diagram shows the distal interference element 1914 fully inserted into the lower bearing recess 2250, where the feature of the actuator 1913 (e.g., a convex six-lobed shape) is already located at the bottom of the corresponding feature of the upper bearing recess 2220 (e.g., a concave lobe), and the interference element 1914 is disposed in the lower bearing recess 2250. Due to the presence of the interference element 1914, the ball bearings 2240 are radially displaced outwards until they extend from the head portion 2218 and into the cavity 2215 of the body 2210. The ball bearings 2240 extend from the head portion beyond the outer diameter of the head portion and extend to the distance at which they interfere with the flange 2211 when driving the proximal screw 519, as shown. Figure 12E and Figure 12F As shown.

[0075] exist Figure 12E and Figure 12FIn this configuration, the anti-reverse actuator 1901 is used to retract the screw 519 from the body 2210 until the ball bearing 2240 reaches the interference position of the flange 2211 (indicated by circle 2299). Because the presence of the interference element 1914 in the lower bearing recess 2250 prevents the ball bearing 2240 from moving radially inward beyond the inner diameter of the flange 2211, the anti-reverse actuator 1901 cannot retract the screw 519 beyond the indicated position. Therefore, once the screw 519 is positioned in the body 2210 beyond the flange 2211 in the channel 2219, the anti-reverse actuator 1901 can only be used to adjust the position of the screw 519, as permitted by the length 2299 of the cavity 2215 below the head portion 2218 when the locked ball bearing 2240 is adjacent to the flange 2211.

[0076] Figure 12G and Figure 12H The image shows the removal of the anti-reverse drive 1901 from the head portion 2218, thereby allowing the ball bearing to move freely radially inward into the lower bearing socket 2250, thus enabling the use of, for example, a standard drive 1812 to retract the screw 519 proximally beyond the flange 2211.

[0077] Figure 13A and Figure 13B Is it through Figures 11A to 12H A top cross-sectional view of the lower bearing recess 2250 of the drive-specific anti-reverse assembly, in which... Figure 13A The ball bearing 2240 is shown in its displaced position (e.g., via the safety feature 1914 provided in the lower bearing socket 2250), and Figure 13B The ball bearing 2240 is shown in a "free" position, where, when there is sufficient space in the bearing socket 2250, it can move inwards in addition to interfering with the flange 2211 when the standard drive tip 1813 is positioned in the socket. In some examples, and as... Figure 13B As shown, channel 2219 may include an inner base 2251 to prevent the ball bearing from falling into the lower bearing socket 2250 and dislodging from channel 2219. In some examples, channel 2219 may include an outer base 2251 to prevent the ball bearing from falling off the head portion 2218 when the head portion 2218 is removed from the body 2210.

[0078] Although the locking body has been shown as ball bearing 2240, other locking bodies are envisioned, such as pins, which may also include springs for inwardly biasing the locking body to ensure that the locking body does not get stuck in an interfering position and to prevent removal of screw 519.

[0079] Figure 14 yes Figures 11A to 12HA photograph of one embodiment of the drive-specific anti-reverse assembly 599 shows a spherical distal end 408 of a body 2210 having a cavity 2215 (not visible) and a screw 519 configured to be disposed within the body 2210 to adjust the position of a tapered member (not shown) disposed at the end of the screw relative to the conical inner surface of the spherical proximal end 408 for expanding the spherical proximal end 408. The head portion 2218 of the screw 519 includes a ball bearing 2240 disposed in a channel 2219. Figure 14 An exemplary anti-reverse drive 1901 is also shown, which has a drive 1913 and an interference element 1914 configured to engage with a socket of a head portion 2218, as described herein.

[0080] It should be noted that any order of method steps expressed or implied in the above description or accompanying drawings should not be construed as limiting the disclosed methods to performing the steps in that order. Rather, the various steps of each method disclosed herein can be performed in any of a variety of orders. Furthermore, since the described methods are merely exemplary embodiments, various other methods including additional steps or fewer steps are also covered within the scope of this disclosure.

[0081] The instruments disclosed herein can be constructed from any of a variety of known materials. Exemplary materials include those suitable for surgical applications, including metals (such as stainless steel, titanium, nickel, cobalt-chromium, or alloys and combinations thereof), polymers (such as PEEK, ceramics, carbon fibers), etc. Various components of the instruments disclosed herein can have varying degrees of rigidity or flexibility to suit their use. The dimensions of the devices can also vary considerably depending on the intended use and the anatomy of the surgical site. Furthermore, specific components may be formed from materials different from other components. One or more components or portions of the instrument may be formed from radiopaque materials to facilitate visualization under fluoroscopic examination and other imaging techniques, or from radiopaque materials so as not to interfere with the visualization of other structures. Exemplary radiopaque materials include carbon fibers and high-strength polymers.

[0082] The devices and methods disclosed herein can be used in minimally invasive and / or open surgical procedures. Although the devices and methods disclosed herein are generally described in the context of spinal surgery on human patients, it should be understood that the methods and devices disclosed herein can be used in any of a variety of surgical procedures on any human or animal subject, or in non-surgical procedures.

[0083] The device disclosed herein may be designed for single-use disposal or for multiple-use applications. However, in either case, the device can be repaired and reused after at least one use. Repair may include any combination of disassembling the device, subsequently cleaning or replacing specific parts, and subsequent reassembly steps. Specifically, the device is detachable, and any number of specific parts or components of the device can be selectively replaced or removed in any combination. After cleaning and / or replacing specific parts, the device can be reassembled for subsequent use at a repair facility or by a surgical team just before surgery. Those skilled in the art will understand that various techniques can be used for disassembly, cleaning / replacement, and reassembly of the device. The use of such techniques and the resulting repaired device are within the scope of this application.

[0084] The device described herein can be processed prior to use in surgical procedures. First, new or used instruments are obtained and cleaned as needed. The instruments can then be sterilized. In one sterilization technique, the instrument may be placed in a closed, sealed container (such as a plastic or TYVEK bag). The container and its contents may then be placed in a radiation field that can penetrate the container, such as gamma radiation, X-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument may then be stored in a sterile container. Sealing the container keeps the instrument sterile until it is opened in a medical facility. Other forms of sterilization known in the art are also possible. This may include beta radiation or other forms of radiation, ethylene oxide, steam, or a liquid bath (e.g., cold immersion). Due to factors such as the materials used, the presence of electronic components, etc., certain forms of sterilization may be more suitable for use in conjunction with different parts of the device.

[0085] Based on the above embodiments, those skilled in the art will understand additional features and advantages. Therefore, this disclosure is not limited to the content specifically shown and described. All publications and references cited herein are expressly incorporated by way of reference in their entirety.

Claims

1. An anti-reverse mechanism, comprising: An anti-reverse mechanism body, the anti-reverse mechanism body being configured to receive a fastener, the anti-reverse mechanism body defining a cavity, the cavity being configured to receive the head of the fastener when the fastener is disposed in the anti-reverse mechanism body, the cavity having an inwardly extending flange defining a proximal opening of the cavity; A fastener having a threaded portion and a head portion, the head portion of the fastener comprising: Upper bearing socket, the upper bearing socket being configured to mate with a driver for adjusting the position of the fastener within the anti-reverse mechanism body; Lower bearing socket; and At least one channel, the at least one channel extending radially from the lower bearing recess and whose size and shape are configured to allow the locking body to translate through the at least one channel; and A locking body is disposed in each of the at least one channel of the fastener. The anti-reverse mechanism has a first configuration when the head portion of the fastener is engaged by the first driver, and a second configuration when the head portion of the fastener is engaged by the second driver. In the first configuration, the engagement of the drive portion of the first driver with the upper bearing recess of the head portion of the fastener allows the locking body to move radially inward in the at least one channel, enabling the fastener to be inserted distally into the anti-reverse mechanism body and removed proximally from the anti-reverse mechanism body without interference between the locking body and the flange of the cavity. In the second configuration, when the fastener is disposed in the anti-reverse mechanism body such that the at least one channel is disposed distal to the flange of the cavity, the engagement of the drive portion of the second actuator with the upper bearing socket includes the engagement of the distal end portion of the second actuator with the lower bearing socket of the head portion of the fastener. This engagement causes the locking body to be radially displaced outward, such that when the fastener is advanced proximally by the second actuator, the locking body interferes with the flange of the at least one channel, preventing the fastener from being removed from the anti-reverse mechanism body by the second actuator.

2. The anti-reverse mechanism according to claim 1, wherein, The locking element is a ball bearing.

3. The anti-reverse mechanism according to any one of claims 1 or 2, wherein, The cavity defines a length below the flange, and the length of the cavity defines the maximum possible adjustment distance of the fastener in the anti-reverse mechanism body of the second configuration.

4. The anti-reverse mechanism according to claim 1 or 2, wherein, The cavity defines a cylindrical inner wall, and the flange is a radial flange.

5. The anti-reverse mechanism according to claim 4, wherein, The inner wall of the cavity defines a width greater than the diameter of the head portion of the fastener plus twice the extension distance of the locking body in the second configuration from the head portion of the fastener.

6. The anti-reverse mechanism according to claim 1 or 2, wherein, The at least one channel is configured to hold the locking body in the radially extending direction.

7. The anti-reverse mechanism according to claim 1 or 2, wherein, The lower bearing recess defines a cylindrical inner wall.

8. The anti-reverse mechanism according to claim 1 or 2, wherein, The upper bearing recess defines a shape configured to mate with the shapes of the drive portions of the first driver and the second driver, and to allow torque to be delivered from the drive portion of the first driver or the drive portion of the second driver to the fastener for adjusting the position of the fastener in the anti-reverse mechanism body.

9. The anti-reverse mechanism according to claim 1 or 2, wherein, The anti-reverse mechanism body includes a threaded portion, which is configured to receive the threaded portion of the fastener.

10. The anti-reverse mechanism according to claim 1 or 2, wherein, In the first configuration, the maximum engagement position of the drive portion of the first driver with the upper bearing recess of the head portion of the fastener is defined by the contact between the drive shaft of the first driver and the upper bearing recess.

11. The anti-reverse mechanism according to claim 1 or 2, wherein, In the second configuration, the maximum engagement position of the distal end portion of the second driver is defined by the contact between the distal end portion and the bottom of the lower bearing recess.

12. The anti-reverse mechanism according to claim 1 or 2, wherein, In at least one of the first configuration or the second configuration, the maximum engagement position of the drive portion of the first driver or the drive portion of the second driver is defined by the contact between the drive feature portion of the drive portion of the first driver or the drive portion of the second driver and the end of the corresponding drive feature portion in the upper bearing socket.

13. A surgical instrument comprising: A retractor body configured to be attached to an implantable anchor; A first organization manipulator is connected to the retractor body and is capable of multi-axis movement relative to the retractor body; as well as A second tissue manipulation device is connected to the retractor body and is capable of multi-axis movement relative to the retractor body; Each of the first tissue manipulation device and the second tissue manipulation device is connected to the retractor body via a multi-axis joint. Each multi-axis joint includes fasteners to selectively lock the multi-axis joint against movement, and Each of the manipulators and fasteners includes an anti-reverse mechanism according to any of the preceding claims, wherein each of the manipulators includes the anti-reverse mechanism body of the anti-reverse mechanism, and the fastener includes the fastener.

14. The apparatus according to claim 13, wherein, The first tissue manipulation device and the second tissue manipulation device are opposite each other, so that they can move toward or away from each other.

15. The apparatus of claim 13 or 14, further comprising a lock coupled to the anti-reverse mechanism body and configured to engage with the anchoring extension to selectively lock the position of the anti-reverse mechanism body relative to the anchoring extension.

16. The apparatus according to claim 13 or 14, wherein, Each of the first and second organizational control devices is connected to the anti-reverse mechanism body via a ball joint.

17. The apparatus according to claim 16, wherein, Each of the ball joints includes an expansion member configured to selectively lock the ball joint to resist movement.

18. A rollback prevention system, comprising: An anti-reverse mechanism body, the anti-reverse mechanism body being configured to receive a fastener, the anti-reverse mechanism body defining a cavity, the cavity being configured to receive the head of the fastener when the fastener is disposed in the anti-reverse mechanism body, the cavity being defined by an inwardly extending flange at a proximal position of the cavity; A fastener having a threaded portion and a head portion, the head portion of the fastener comprising: Upper bearing socket, the upper bearing socket being configured to mate with a driver for adjusting the position of the fastener within the anti-reverse mechanism body; Lower bearing socket; and At least one channel, the at least one channel extending radially from the lower bearing recess and whose size and shape are configured to allow the locking body to translate through the at least one channel; and A locking body, wherein the locking body is disposed in each of at least one channel of the fastener; and A locking actuator includes a distal end region sized and shaped to engage both the upper and lower bearing recesses. The distal end region has a driving portion and a locking portion located distal to the driving portion. The driving portion is configured to abut the upper bearing recess to deliver torque to the fastener for adjusting its position within the anti-reverse mechanism body. The locking portion is configured to be positioned within the lower bearing recess when the driving portion abuts the upper bearing recess, and its size and shape are configured to radially displace the locking body to prevent proximal movement of the locking body within the fastener beyond the flange. This includes a standard driver at the distal end having a driving portion but not a locking portion whose size and shape are set to move the locking body radially outward. The standard driver is capable of delivering torque to the upper bearing socket to adjust the position of the fastener in the anti-reverse mechanism body proximally and distally without causing interference between the locking body and the flange.

19. The anti-backflow system according to claim 18, The anti-reverse mechanism is a first body, and the system also includes a second body configured to be connected to an implantable anchor. The first body defines at least a portion of the manipulator, which is configured to be connected to the second body and capable of multi-axis movement relative to the second body. The manipulator is connected to the second body via a multi-axis connector, and The fasteners are positioned in the first body to selectively lock the multi-axis joint to resist movement.

20. A method for assembling and adjusting the position of a fastener in a locking mechanism, the method comprising: Insert the fastener into the body of the locking mechanism; The first driver is coupled to the fastener and the first driver is used to screw the fastener distally into engagement with the body of the locking mechanism, such that the locking body disposed in the radially extending channel of the fastener is disposed distal to the inwardly extending flange in the cavity of the body of the locking mechanism. When the fastener is threadedly engaged with the body of the locking mechanism, a second driver is connected to the fastener. The second driver causes the locking body to be radially displaced outward, such that the locking body interferes with the flange of the radially extending channel to prevent the fastener from moving proximally beyond the position where the locking body abuts the flange. as well as The position of the fastener in the body of the locking mechanism is adjusted using the second actuator by screwing the fastener into the body between a maximum proximal position and a maximum distal position defined by the interference between the locking body and the flange.

21. The method according to claim 20, wherein, The locking element is a ball bearing.

22. The method according to any one of claim 20 or 21, wherein, The main body of the locking mechanism includes a collet disposed in a socket, and wherein inserting the fastener into the main body of the locking mechanism includes connecting the distal end of the fastener to an expansion member disposed in the collet, such that adjusting the position of the fastener in the main body of the locking mechanism causes the collet in the socket to expand and contract and adjusts the level of frictional engagement between the collet and the socket.

23. The method according to claim 22, wherein, The locking mechanism's body is a first body defining at least a portion of the manipulator, and the socket is part of a second body configured to be coupled to an implantable anchor. The method further includes coupling the chuck to the socket after inserting the fastener into the first body using the first actuator. The chuck and the socket define a multi-axis joint. Adjusting the position of the fastener in the body of the locking mechanism using the second actuator includes selectively locking the multi-axis joint to resist movement.

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