Abstract: Devices and methods for fixating a graft tendon in a bone tunnel for a ligament reconstruction or repair procedure are provided. In general, the described implantable tissue fixation device includes first and second elongate, substantially rigid support members that are discrete elements separated from each other, and at least one flexible member connecting the rigid support members. The tissue fixation device can have changeable dimensions such that it has at least one dimension that is smaller in a delivery configuration than in a deployed configuration. In both delivery and deployed configurations, the first and second rigid support members are positioned in a non-intersecting orientation with respect to one another. A graft retention loop coupled to the tissue fixation device has the graft tendon coupled thereto and extending into the bone tunnel so as affix the graft into the bone.

Abstract: A receiver assembly for securing an elongate rod to a bone anchor includes a receiver having pair of upright arms that define an open channel configured to receive the elongate rod, a discontinuous helically wound receiver guide and advancement structure formed into the interior surfaces of the upright arms, and horizontally-elongated tool engaging grooves formed into upper portions of the outer surface of the upright arms. The receiver assembly further includes a closure configured for positioning within the open channel to secure the elongate rod to the receiver in a locked configuration, with the closure having an outer surface with a mating continuous helically wound closure guide and advancement structure configured to resist a tendency toward splaying between the upright arms upon a screwing in of the closure within the open channel by rotatable engagement with the receiver guide and advancement structure.

Abstract: An intramedullary nail may include a shank with a centerline defined along a length thereof. The intramedullary nail may also include a channel with a channel axis transverse to the centerline. The channel may have an obround shape in a first cross-sectional plane perpendicular to the channel axis at the centerline and a tapered profile in a second cross-sectional plane containing the channel axis. A proximal edge of the channel within the second cross-sectional plane may form a first angle relative to the channel axis and a distal edge of the channel within the second cross-sectional plane may form a second angle relative to the channel axis that is different from the first angle.

Abstract: A pivotal bone anchor assembly includes a shank having a head portion and an anchor portion for fixation to the bone of a patient, and a receiver comprising a base defining a lower portion of central bore and a pair of upright arms defining a channel for receiving an elongate rod. The assembly also includes a retaining structure with a central opening configured to capture and pivotally retain and support the head portion of the shank in the retaining structure, and which is slidably movable relative to the receiver so as to provide for increased articulated movement between the shank and the receiver prior to locking the assembly with the elongate rod and a closure. The assembly further includes an insert configured to engage the elongate rod and the head portion of the shank when in use, and to have an overlapping configuration with the retaining structure when the assembly is in the locked configuration.

Abstract: Disclosed implants may include a first implant receiver and a second implant receiver each having an upper portion and a lower portion connected together by an arm portion, for example. In various embodiments, the upper and lower portions may define a longitudinal passageway extending through the upper and lower portions in a longitudinal direction of each implant receiver, and the arm portions may each define a rod passageway extending in a lateral direction, for example. In various embodiments, each receiver may include a crown having an outside thread pattern threadably engaged within the longitudinal passageway and for mating with a corresponding nut having a similar interior thread pattern. In various embodiments, a rod may extend in the lateral direction through the rod passageways In various embodiments, in a non-tightened position, the rod may freely move and in a tightened position, the arms constrain the rod from moving.

Abstract: Systems, instruments, and methods for surgical navigation with verification feedback are provided. The systems, instruments, and methods may be used to verify a trajectory of a surgical tool during a procedure. The systems, instruments, and methods may receive one or more captured images of an anatomical portion of a patient; execute a surgical plan to insert the surgical tool into the anatomical portion; receive sensor data collected from one or more sensors being inserted into the anatomical portion; determine whether the sensor data corresponds to the surgical plan; and send, in response to determining that the sensor data does not correspond to the surgical plan, an alert indicating that the surgical tool is not being inserted according to the surgical plan. The one or more sensors may be attached to the surgical tool.

Abstract: An assembly includes a flexible fixation member, a suture, and a delivery device. The fixation member includes a body with two terminal ends. A suture passes through the flexible fixation member at various points along a length of the body such that portions of the fixation member are slidable relative to the suture and configurable to form a cluster within a surgical site. The delivery device includes a tubular member, an elongated inserter, and a trigger. The elongated inserter is slidably disposed within the tubular member. The inserter has a forked distal end configured to receive a portion of the flexible fixation member and the suture. The trigger is finger-engagable and fixedly coupled to the proximal end of the inserter. It is configured to advance and retract the inserter relative to the tubular member. The trigger includes a retention member for retaining a proximal end portion of the suture.

Abstract: A pivotal bone anchor assembly includes a receiver comprising a base defining a central opening and upright arms defining an open channel for receiving a rod and including tool engaging structures for releasable overlapping engagement with an insert compressing tool. The assembly further includes a bone anchor comprising a capture head pivotably positionable within the central opening of the base and an anchor portion for fixation to the bone, and a compression insert positionable within the central opening above the capture head and comprising an upper surface engageable with the rod, a center through-bore, and upward-facing tool engagement surfaces located radially outward from the center through-bore.

Abstract: Surgical drill guides have modular configurations and are adapted to accommodate a wide range of anatomy. The surgical drill guides are adapted to be removed while leaving a guide wire in its intended location in human bone. The distal end of the drill guide acts as a safety stop for the guide wire by preventing the guide wire from penetrating too far past the far side of the bone.

Abstract: Disclosed is a bone screw fixation device including two screws and only two. The bone screw includes: a first screw provided at its proximal end with a head for compressing the bone by an end-abutment; and a second screw provided at its distal end with a bone threading having a first helix pitch and at its proximal end with a bone threading having a helix with a pitch smaller than the first helix pitch.

Abstract: An anchoring member for a polyaxial bone anchoring device includes a bone anchoring section having a first end, a second end, and a bone engagement structure, a head having an outer surface portion that defines a segment of a sphere, wherein a central axis extends through the head and the first and second ends of the bone anchoring section, and a neck extending between the first end of the bone anchoring section and the head. The neck has a first portion and a second portion between the first portion and the bone anchoring section. In at least a first cross-sectional plane including the central axis, the first portion of the neck is concave with a first curvature, and the second portion of the neck is concave with a second curvature that is less curved than the first curvature.

Abstract: Various devices, systems, and methods for knotless suture anchors are provided. In general, a guide device can be cannulated and can be configured to slidably receive therein an inserter tool configured to deliver a suture anchor into a hole formed in bone, such as with a drill advanced through the guide device. The guide device with the inserter tool therein can be configured to be held as a unit by one hand of a person, e.g., a surgeon or other medical personnel.

Abstract: A bone screw comprises a shaft defining a longitudinal axis and a minor diameter. The shaft including a core having an angled surface relative to the axis. The angled surface extending from the minor diameter adjacent a proximal portion of the shaft to a distal portion of the shaft, and a wall disposed about the angled surface. The wall including at least one thread having an external thread form. In some embodiments, systems, spinal constructs, surgical instruments and methods are disclosed.

Abstract: A bone anchor assembly for securing an elongate rod to a bone of a patient includes a receiver having a central bore with interior opposed recesses having downwardly-facing top surfaces, and a shank with a head portion confiugred for positioning within the central bore with the body of the shank extending downwardly through a bottom opening. The assembly also includes an insert that is positionable into the central bore above the shank head, the insert including opposed extensions configured to inhibit rotation between the receiver and the insert, and upright arms having top surfaces complementary with the interior opposed recesses of the central bore. The top surfaces of the insert arms are configured to snap under and engage the downwardly-facing top surfaces of the interior opposed recesses so as to establish a frictional non-floppy relationship between the shank and the receiver and to prevent the insert from moving back up within the central bore.

Abstract: Bone compression screws are characterized by a two-piece compression screw assembly comprising a screw component and a sleeve component. The screw component has external male bone screw threading at a distal end, external male machine screw threading on a proximal end, and a smooth shank between the threaded distal and proximal ends. The screw component may be solid, cannulated, slotted, fenestrated, fluted, helically fluted, or any combination thereof. The sleeve component has external male bone screw threading with a pitch that can be equal to, smaller than, or greater than the thread pitch of the screw component, an internal bore extending from a proximal end of the sleeve component to the distal end of the sleeve component and sized for reception over the proximal end of the screw component. Internal female machine screw threading is configured to mate with the external male machine screw threading of the screw component.

Abstract: Described herein are examples of orthopedic drill bits and methods of preparing a bone of a living being for fixation. An example method includes coupling a drive attachment of a drill bit to a mounting attachment of a driver, and placing a guide at a desired location on the bone. The guide has an opening corresponding to an area of bone to be removed. The guide provides proper positioning and alignment for drilling a hole. With the guide in place, the method further includes aligning the drill bit with the opening on the guide and drilling a hole in the bone. Once the hole is drilled, the method includes de-coupling the drill bit from the driver, and bending the drill bit at the drive attachment while the drill bit is still in the bone. In some examples, additional method steps follow preparation of the hole.

Abstract: Anchor deployment systems and tools are provided. An anchor deployment tool can include a flexible tube including a distal anchor manipulation portion. The tool can also include a deployment element, which is positionable within the flexible tube, and is configured to, while the distal anchor manipulation portion is proximate an implantable device, (i) engage the anchors in the flexible tube, (ii) advance each of the anchors in a distal direction to the distal anchor manipulation portion, and (iii) anchor the implantable device to tissue of a subject by deploying each of the tissue anchors through the implantable device and into the tissue.

Abstract: The various embodiments disclosed herein relate to bone fixation or fusion devices, including intramedullary fixation or fusion devices that are implanted around the target bone. Certain device embodiments relates to devices that can be bent or otherwise deformed to replicate the natural or desired curve of the bone or joint being treated. In addition, other embodiments relate to implantation devices that can be used to implant or position the bone fixation or fusion devices.

Abstract: Illustrative embodiments of orthopedic implants and methods for surgically repairing hammertoe are disclosed. According to at least one illustrative embodiment, an orthopedic implant includes a proximal segment comprising a number of spring arms forming an anchored barb at a first end of the implant, a distal segment extending between the proximal segment and a second end of the implant, and a central segment disposed between the proximal and distal segment.

Abstract: Apparatus and method for fixing a bone using a plate and a coupler that are connected to one another with flexible members. The plate may be configured to be attached to a shaft region of a bone. The coupler may be configured to be disposed on an end region of the bone, and may define a bore and an aperture. The flexible members may include a first flexible member and a second flexible member, each including a wire or cable. The first flexible member may be configured to extend from the plate, through the bore, and back to the plate. The second flexible member may be configured to extend from the plate to the coupler on a path that approaches the coupler transverse to a line that is parallel to the bore. The apparatus and method may be used to stabilize the greater trochanter of a femur.

Abstract: Provided are a bone fixation screw apparatus and a fastening method thereof. More particularly, provided are a bone fixation screw apparatus and a fastening method thereof including a bone screw which is inserted to a lower side of a receiving portion and has a spherical head formed at a proximal end, a collect chuck which is inserted to an upper side of the receiving portion to be connected with the spherical head of the bone screw inside the receiving portion, and a rod which is seated on an upper side of the collet chuck and fixed through a fixing screw fastened to the receiving portion, in which the bone screw and the collet chuck are introduced to the receiving portion in opposite directions to each other. Therefore, it is possible to firmly and easily fasten the bone screw and the collet chunk and prevent the bone screw from being easily separated by external force.

Abstract: A bone implant includes a proximal end, a distal end, a first portion extending between the proximal and distal ends having a maximum and minimum portion height, and a second portion extending between the proximal and distal ends having a maximum and minimum portion height. The second portion is connected to the first portion at the proximal end and the distal end and at least one of the first portion and the second portion is moveable relative to the other of the first portion and the second portion so as to transition the bone implant between a relaxed state wherein the first and second portions are separated by a first distance and a contracted state wherein the first and second portions are separated by a second distance different from the first distance. At least one of the proximal end and the distal end have the minimum portion height.

Abstract: Disposable torque-limiting gearless device with speed reduction. Torque-limiting interfaces having a plurality of undulations arranged around an axial bore or drive socket and separated by a plurality of transition regions configured to engage and disengage to provide torque transmission with predetermined torque limits at various rotational speeds and for amounts of actuations while remaining within a specified operational range. The reduction assembly integral to the gearless torque limiting assembly provides a drive shaft having an input segment, an eccentric segment, and an output segment, wherein the input segment and the output segment each have a centerline running along a same first axis, and wherein the eccentric segment has a center line running along a second axis, the second axis being parallel to the first axis and positioned a first distance away from the first axis.

Abstract: Implantable devices for fixation of curved bone such as the pelvic ring pubic symphysis and acetabulum, and methods for the use of the devices are disclosed. The implantable devices are convertible between a flexible state and a rigid state, and include an elongate structure having a proximal bone interface, a main body, and a distal bone interface. In a flexible state, the devices may be inserted along, and conform to a curved pathway, and in the rigid state, the devices may support the mechanical loads required to fixate a fracture.

Abstract: In one embodiment, a bone fixation plate has first and second ends spaced apart along a first direction so as to define a length, and third and fourth ends spaced apart along a second direction so as to define a height that is less than the length. The plate has an inner and outer surface spaced apart along a third direction so as to define a thickness that is less than both the height and length. Openings extend from the inner surface to the outer surface along the third direction and are spaced apart along the first direction. Further, the plate has tangs that are offset from the openings with respect to the second direction, and extend out with respect to the outer surface along the third direction. The tangs are spaced apart from one another along the first direction, and are configured to receive a securement device.

Abstract: Provided is a modular pedicle screw assembly which includes various components that may be configured in various manners so as to provide different functionalities to the pedicle screw assembly. This advantageously decreases surgery time, reduces repetitive and tedious surgical steps, and allows for streamlining inventory of expensive medical equipment. In one embodiment, a pedicle screw assembly includes a pedicle screw, a rod holding element, an insert, a rod, and a set screw. The insert may have a uniplanar configuration which allows movement of the insert, prior to final attachment, in a plane of motion. The insert may optionally have a monoaxial configuration which prevents movement of the insert. A method is also provided for securing a rod to a pedicle screw assembly. Also provided is an assembly tool for use in assembling a pedicle screw assembly.

Abstract: Temporary, radiographically opaque, bone markers having first and second penetration members that are concentric with one another and are configured to pierce bone are provided herein. Bone markers can non-exclusively be used to help verify the correct surgical site along the vertebrae, locate the vertical midline, and as a fixed point for aligning surgical instruments. Insertion and extraction devices for use with the bone markers are also provided herein.

Abstract: Devices, systems, and methods are provided for gauging a bone tunnel. In one exemplary embodiment, a graft repair system can include an elongate pin, an elongate pusher shaft configured to be positioned over one opposed end of the pin when the pin is positioned within a bone tunnel, and a gauge member configured to be positioned over another opposed end of the pin when the pin is positioned within the bone tunnel. When the pusher shaft abuts the bone adjacent one of the open ends of the bone tunnel and the gauge member abuts the bone adjacent the other open end of the bone tunnel, an indicator mark on the pin can be visible through one or more windows formed in the gauge member. The indicator mark's position relative to each of the one or more windows can indicate one or more characteristics related to the bone tunnel.

Abstract: The invention relates to a device for penetratingly extending a blind hole into a hard tissue, particularly a jawbone. The device is characterized in that it comprises a tubular body (1) having a distal working opening (2) and an inlet (3) opposite the working opening (2), said inlet being closed by a sealing element (4) that is penetrated by a shaft (5) of a working tool, for example a milling tool (5, 6), and allows at least a feed motion, a drive motion and a steering motion of the working tool (5, 6), the tubular body (1) being provided with a connection (8) for applying an internal pressure.

Abstract: The disclosure describes methods of making high-strength NDGA collagen and associated methods of preparing collagen preparatory material and medical bioprostheses.

Abstract: A helicoil interference fixation system comprising: a helicoil comprising a helical body comprising a plurality of turns separated by spaces therebetween, the helical body terminating in a proximal end and a distal end, and at least one internal strut extending between at least two turns of the helical body; and an inserter for turning the helicoil, the inserter comprising at least one groove for receiving the at least one strut; the helicoil being mounted on the inserter such that the at least one strut of the helicoil is mounted in the at least one groove of the inserter, such that rotation of the inserter causes rotation of the helicoil.

Abstract: A material-fastening device and related fastener and methods for use, and more particularly, a device with segments of the fastener capable of being independently attached to different sides of a gap in the material.

Abstract: Biomedical implant fastener systems, such as bone screw systems and the like. In some embodiments, a fastener may comprise a first plurality of teeth, and a washer configured to be received on the fastener may comprise a second plurality of teeth configured to be engaged with the first plurality of teeth. The first plurality of teeth may be configured to engage with the second plurality of teeth such that so as to allow for selective rotation between the washer and the fastener in a first rotational direction and so as to prevent rotation between the washer and the fastener in a second rotational direction opposite from the first rotational direction when the fastener is engaged with the washer such that second plurality of teeth is engaged with the first plurality of teeth so as to prevent the fastener from backing out of the washer after engagement.

Abstract: A vented set screw is used to secure a connection between an implantable medical device and an implantable lead. The vented set screw includes one or more venting channels that allow liquid and/or gas to flow out of the implantable medical device when the implantable lead is being inserted into the implantable medical device and secured during an implantation procedure. This prevents pressure from building up at the connection, thereby ensuring proper performance of sensing and/or therapy delivery functions of the implantable medical device.

Abstract: Surgical instruments are disclosed in which an elongated shaft is used in conjunction with a separate, remotely actuable tool head for performing a procedure on a target tissue. The shaft has a tool engagement member carried at its distal end that is remotely actuable through the shaft to engage and release the tool head.

Abstract: The present disclosure relates to a suture anchor. The suture anchor includes a body having a proximal end and a distal end, the body including threads along at least a partial length of the body and at least one through hole, the threads including a profile such that the threads located near the distal end of the body include a first shape and the threads located near the proximal end of the body include a second shape different from the first shape. Delivery devices and anchor dilators are also disclosed.

Abstract: Removable drill guide tips are provided for simultaneous assembly relative to the holes of a bone plate. The drill guide tips are used as a guide for a drill bit without any additional extension and then removed with a tool to allow insertion of a screw within the same hole in the bone plate. Alternatively, the drill guide tips may be used with an extension to extend the effective length of the drill guide.

Abstract: A spinal alignment correction system (1) has a posted lumbar pedicle screw called a MAC Pin (10) which has an elongated shaft (11) and a rod coupler assembly (20) and a cannulated tower (40). The elongated shaft (11) has an inner pedicle screw portion (12) with pedicle threads (12A), an outer second thread portion (14) with second threads (14A) and a transition or intermediate portion (16) disposed between the pedicle screw portion (12) and the second thread portion (14). The cannulated tower (40) when mounted over said elongated shaft (11) abuts said coupler (20) along an outer cam surface and further tightening rotation of the cannulated tower (40) causes outward movement of the elongated shaft (11). The system (1) allows for a controlled alignment correction of malaligned vertebral bodies using a number of methods used to correct a variety of indications.

Abstract: An intramedullary fixation device having a distal section; a proximal section; a connecting member for adjustably securing the distal and proximal sections end to end along a longitudinal axis; means for securing the proximal section to a first bone; and means for securing the distal section to a least one different bone. The connecting member is rotated to provide compression across a bone arthrodesis site to be stabilized and fused. Also described is a method of utilizing the intramedullary fixation device with an outrigger assembly.

Abstract: A spinal fixation system includes a rod and anchor devices that include a bone engaging fastener having a head defining a spherical socket. A ball insert is placed within the socket and rotated so that the ball insert is juxtaposed with the socket. The anchor device further includes a yoke defining a yoke channel for receiving the rod and a stem engaged to the ball insert captured within the socket. A sleeve disposed between the yoke channel and the fastener head supports the rod. A set screw is operable to clamp the rod against the sleeve and draw the insert into engagement within the socket. A releasable detent defined between the yoke and the fastener head is configured to releasably retain the yoke in at least one discrete position relative to the fastener. Portions of the releasable detent may also exert a frictional retention force against the fastener head.

Abstract: Removable drill guide tips are pre-assembled into threaded holes of a bone plate. The tips may be used with an extension to together function as a conventional drill guide. After drilling, the extension or another tool is used to remove the tips from the plate. According to another use, the tip is used as a guide for a drill bit without any additional extension and then removed with a tool.

Abstract: The present disclosure provides a sternal closure fixation device. The fixation device includes a first sternum implant disposable within an interior cavity of a first half of a severed sternum such that the first implant contacts opposing anterior and posterior faces of the cavity. The fixation device additionally includes, a second sternum implant disposable within an interior cavity of a second half of a severed sternum such that the second implant contacts opposing anterior and posterior faces of the cavity. Furthermore, the fixation device includes a rigid fixation pin sized and structured to be disposed within an internal bore of the first implant and within an internal bore of the second implant, whereby when the first and second halves of the severed sternum are joined together, the first and second halves of the sternum are prevented from shear movement in any direction relative to each other.

Abstract: A method of repairing bone. In the method, a sleeve and a fastener may be provided, with the fastener projecting from the sleeve and having a trailing section disposed in threaded engagement with the sleeve. A leading section of the fastener may be driven into threaded engagement with bone. The sleeve may be advanced into contact with the bone to apply tension to the fastener and compress the bone. A trailing section of the fastener may be driven out of the sleeve and into threaded engagement with the bone.

Abstract: A pin assembly for operation includes a hollow pin for operation having a plurality of side holes defined through an outer surface thereof and a head which is closed or open due to the presence of a through-hole; a hollow support having a pin fastening part formed therein in the shape of a groove to fasten one end of the pin for operation, and being open at both ends thereof, and a hollow injector for insertion into an insertion hole formed in the support, wherein the hollow pin for operation is fastened to the pin fastening part of the support, and by applying external force to one end of the support, the hollow pin for operation is inserted into a bone.

Abstract: A spinal fixation system includes a rod and anchor devices that include a bone engaging fastener having a head defining a spherical socket. A ball insert is placed within the socket and rotated so that the ball insert is juxtaposed with the socket. The anchor device further includes a yoke defining a yoke channel for receiving the rod and a stem engaged to the ball insert captured within the socket. A sleeve disposed between the yoke channel and the fastener head supports the rod. A set screw is operable to clamp the rod against the sleeve and draw the insert into engagement within the socket. A releasable detent defined between the yoke and the fastener head is configured to releasably retain the yoke in at least one discrete position relative to the fastener. Portions of the releasable detent may also exert a frictional retention force against the fastener head.

Abstract: A method for attaching an elongated object to bone, the method comprising: forming a hole in the bone; positioning a loop of the elongated object in the hole; advancing a surgical wire into the bone so that the surgical wire is directed toward a location within the interior of the loop; and severing the surgical wire intermediate its length so as to create a distal portion and a remainder portion and, if the distal portion of the surgical wire does not extend through the loop, further advancing the distal portion of the surgical wire so that it extends through the loop.

Abstract: Methods for fixation of a soft tissue graft in a bone including: forming in the bone a tunnel defining an entrance opening and an exit opening at opposite ends of the tunnel, the tunnel including an anterior wall surface and a posterior wall surface opposite to the anterior wall surface; positioning the soft tissue graft within the tunnel such that the soft tissue graft extends through both the entrance opening and the exit opening of the tunnel; inserting a graft fixation apparatus into the tunnel and driving spikes of the graft fixation apparatus into the posterior wall surface to mount the graft fixation apparatus to the posterior wall surface of the tunnel such that the graft fixation apparatus is anterior to the posterior wall surface and is not recessed beneath the posterior wall surface; and securing the soft tissue graft inside the tunnel with the graft fixation apparatus.

Abstract: A bone fracture fixation system comprises a bone plate configured to bear against a proximal surface of the bone and a plurality of elongated tension elements, each sized to pass through an opening in the bone plate and through the bone from the proximal surface to a distal surface thereof. Each tension element is anchored to the bone and maintained in tension by a distal anchor attached to said tension element and configured to engage the distal surface of the bone and a proximal anchor engageable between the bone plate and the tension element. In one method for fixation of a bone fracture, the bone plate is positioned on a proximal surface of the bone while the tension element is introduced into the bone and through an opening in the bone plate from an opposite distal surface of the bone.

Abstract: A method of performing vertebral facet fusion by lateral approach and related devices. The lateral approach to facet fusion involves identifying the lateral mass and introducing any of the fixation methods known or described herein laterally at one or more facets through the use of a Kirschner wire guide, a cannulated bone drill and cooperatively cannulated staple guide. A surgical bone staple have a perforated bridge is used across the lateral facet joint where fixation is required. Where fusion is desired, a bone screw have lateral perforations of the shank is inserted through the cannulated staple guide and bridge perforation at the joint to promote fusion. A staple cap and graft container for overlay grafting may be utilized for additional fusion. The method involves less surgical time, reduced blood loss and discomfort for the patient as compared to the posterior approach.

Abstract: An apparatus for provisionally locking a polyaxial head on a fixed head of a bone screw using a locking bushing includes an elongated housing with a proximal end and a distal end, the distal end having couplers for releasably coupling with the polyaxial head; an inner shaft slidably engaged within the housing and including a distal portion, a middle portion, and a proximal portion; and an actuator that selectively positions the inner shaft within the housing to engage at least one of the distal portion, the middle portion, and the proximal portion with at least one of the couplers and the bushing disposed between the distal portion and the fixed head of the bone screw.