Abstract: Devices, systems, and methods of bone fixation. The bone fixation system includes a bone plate having an upper surface and a lower surface configured to be in contact with bone, the bone plate having a locking hole extending from the upper surface to the lower surface. The locking hole is configured to receive a locking fastener. The locking fastener has a threaded head portion configured to engage and lock to the bone plate.

Abstract: Apparatus and method for securely fixating an anterior portion of a calcaneus to a reduced posterior facet portion of the calcaneus, using a plate that may allow for stable fixation between the anterior calcaneus, the reconstructed posterior facet, and the posterior tuberosity, and a barrel that may be rotated into the best position to allow posterior screws to enter the best quality bone in the posterior tuberosity. The appropriate height may be set by rotating a push screw, thereby engaging the barrel, and pushing the posterior tuberosity distally.

Abstract: A disc replacement device including a first body member with a convex articulation surface and a second body member with a concave articulation surface is disclosed. When operably positioned, the convex articulation surface engages the concave articulation surface to provide for movement therebetween. The disc replacement device also includes a first opening in the first body member and a second opening in the second body member, wherein the openings are angled and extends from the front aspects of the body members through the external surfaces. The disc replacement device further includes at least two bone fasteners for insertion into the first and second openings to secure the disc replacement device to a first and second vertebra. An interbody motion device and fusion implant, as well as a surgical method for implantation are also disclosed.

Abstract: An intervertebral spacer assembly may include a first intervertebral spacer with a superior surface configured to engage a superior vertebral body, an inferior surface configured to engage an inferior vertebral body, and a proximal surface with a first fastener channel. The assembly may further include a first fastener and a locking member with a first anti-backout member. The first intervertebral spacer or the locking member may have a locking member channel. The other may have a compressible collet insertable into the locking member channel to couple the locking member to the first intervertebral spacer such that the locking member is rotatable relative to the first intervertebral spacer between an unlocked position in which the first anti-backout member does not obstruct the first fastener channel, and a locked position in which the first anti-backout member obstructs the first fastener channel to retain the first fastener in the first fastener channel.

Abstract: An implant includes a curved first plate section having a curvature about a longitudinal axis extending in a longitudinal direction. The first plate section has a first hole and a second hole. The first hole and the second hole are positioned to receive respective bone screws for attaching the implant to a first curved surface of a bone having a syndesmosis. A second plate section extends continuously from the first plate section. The second plate section has at least a third hole that is positioned to be offset from the first hole and the second hole in a direction that is anterior or posterior from the first hole and the second hole in a case where the longitudinal axis is aligned along a superior-inferior direction. The third hole is configured to receive at least one screw or at least one button for holding a suture at a position offset from the first line segment hole and the second hole in the anterior or posterior direction, for reducing the syndesmosis.

Abstract: A surgical fastener manipulation tool in accordance with embodiment of the present invention is useful by a surgeon to place fasteners such as threaded screws. The surgical fastener manipulation tool selectively engages a mating structure of fastener for securing the fastener thereto. Thus, advantageously, the surgical fastener manipulation tool can be used for placing such fasteners and/or can be used for extracting (i.e., removing) such fasteners. The ability to extract a fastener (e.g., a threaded bone screw) with the same tool used for placing it is highly beneficial due to time savings during a surgical procedure and is advantageous with respect to prior art fastener manipulation tool configurations that require placement and extraction tools to be differently configured.

Abstract: Devices, systems, and methods of bone stabilization. The bone stabilization system includes a bone plate having an upper surface and a lower surface configured to be in contact with bone, the bone plate having an opening extending from the upper surface to the lower surface. The opening is configured to receive a fastener, which may be either a locking fastener or a compression fastener. The locking fastener has a threaded head portion configured to engage and lock to the bone plate, and the compression fastener is configured to dynamically compress the bone.

Abstract: An implant is disclosed that has a base member, an articulating member, and a coupling portion that secures the base member to the articulating member. The implant can be a shoulder implant (100, 200, 300) that has a baseplate (102, 230, 310), an articulating component (104, 210), and a fixation component (106, 270, 342). The baseplate includes a first side (110, 234, 314) with a projection (108, 240, 320) that has a first Morse taper and may be offset from a center line of the baseplate and a second side (116, 236, 316) that has a post or stem (114, 250, 330) that is offset from the center line of the baseplate. The articulating component includes a cavity (122, 220) with a second Morse taper that is offset from a center line of the articulating component. The articulating component is attachable to the baseplate when the projection is received in the cavity of the articulation component.

Abstract: An energy transfer system includes a spinal implant having an antenna, an antenna extender attached to a portion of the spinal implant in proximity to the antenna, and a reader device configured to send energy to the spinal implant via the antenna extender. The antenna extender extends away from the spinal implant. The spinal implant is configured to be positioned within a spinal area of a patient.

Abstract: A plate assembly for engaging at least two vertebral bodies of a human spine along the anterior aspect of the spine has a plate and at least two cam locks. The plate has a lower surface for contacting the vertebral bodies and an upper surface opposite to said lower surface. The plate assembly has a plurality of bone fastener receiving holes extending through said plate assembly from said upper surface to said lower surface. The plate has at least a first pair and second pair of said bone fastener receiving holes. The first pair is associated with a first of the vertebral bodies. The second pair is associated with a second of the vertebral bodies. A recess is associated with each of said at least first pair and second pair of said bone fastener receiving holes.

Abstract: A spinal implant includes an intermediate portion and a first portion extending in a transverse orientation from the intermediate portion. The first portion includes an inner surface connectable with vertebral tissue adjacent a lamina. A second portion is spaced from the first portion and extends in a transverse orientation from the intermediate portion. The second portion includes an inner surface connectable with vertebral tissue adjacent a lamina. At least one of the first portion and the second portion includes an outer surface having a mating element engageable with a mating element of a surgical instrument. Systems, surgical instruments and methods are disclosed.

Abstract: A vertebral fixation plate assembly for securing adjacent vertebral bodies is provided that is configured to distract or extend along its length, as well as provide multiple degrees of freedom between the fixation points and the vertebral fixation plate in order to accommodate different installation locations, as well as different surgical approaches. Methods of using the vertebral fixation plate assembly are also provided.

Abstract: An insertion assembly may include a DTS guide and an inserter tool configured to couple an intervertebral spacer having a fastener channel configured to receive a fastener and a locking member channel with a first engagement feature. The inserter tool may include a second engagement feature configured to engage the first engagement feature and removably couple the inserter tool with the intervertebral spacer. The DTS guide may include a shaft lumen configured to receive the inserter tool and slidably couple with the inserter tool. The DTS guide may also include a DTS guide channel configured to receive the fastener and a DTS guide wing. The DTS guide wing may abut against a surface of the intervertebral spacer to align the DTS guide channel with the fastener channel and guide the fastener through the DTS guide channel and into the fastener channel.

Abstract: An insertion assembly may include a flexible tool and a DTS guide configured to engage an intervertebral spacer having a fastener channel oriented at a first angle. The DTS guide may include a DTS guide channel oriented at the first angle which may be aligned with the fastener channel. The flexible tool may include a flexible shaft and a working member disposed at a distal end of the flexible shaft. The working member may be received through the DTS guide channel at the first angle. At least a portion of the flexible shaft adjacent the DTS guide member may flex while the working member is received through the DTS guide channel, such that a distal portion of the flexible shaft may be at a greater absolute angle relative to a DTS guide shaft than a proximal portion of the flexible shaft.

Abstract: An intervertebral spacer may include a fastener channel configured to receive a fastener, a locking member channel, and a locking member. The locking member channel may include an inner wall and one or more inner wall engagement features. The locking member may include an anti-backout member, a collet retainable within the locking member channel, and one or more collet engagement features. The locking member may be rotatable within the locking member channel between an unlocked position and a locked position. The one or more collet engagement features may engage the one or more inner wall engagement features in order to retain the locking member in either the unlocked position or the locked position, such that the anti-backout member may selectively obstruct the fastener channel and prevent the fastener from backing out of the fastener channel.

Abstract: A spinal plate assembly comprising a base plate defining an opening adjacent at least one aperture for receiving a bone screw which attaches to spinal vertebrae. The aperture includes a seat and an annular groove having an end wall. The assembly comprises a locking mechanism having a split ring partially recessed within the annular groove and moveable between a locked condition partially blocking the aperture for retaining the screw in the seat and an unlocked condition radially deformable into the annular groove for permitting screw removal. The split ring has a proximal end and a distal end. The distal end is configured to engage the end wall of the annular groove. The locking mechanism comprises a rotating member retained within the opening of the base plate and having a notch configured to engage the proximal end of the ring to drive the ring toward the unlocked condition.

Abstract: The present invention relates to an anterior cervical spine plate which is used to perform anterior fixation surgery on a cervical spine in orthopedic surgery and neurosurgery, which includes: a plate body formed to extend in a longitudinal direction thereof; two or more bone screw holes formed in the plate body to support head parts of bone screws; and a locking element configured to maintain the bone screws while being inserted into the bone screw holes, respectively. The locking element is rotatably coupled to the plate body, and the plate body has reinforcing parts formed at outer circumferences thereof.

Abstract: A system for bone transport is provided, the system comprising: an adjustable length implant configured for intramedullary placement and comprising a first end configured to be coupled to bone and a second end configured to be coupled to bone, wherein the first end and the second end are displaceable relative to each other along a longitudinal axis; and a driving element configured to be non-invasively activated to displace the first and second ends relative to one another along the longitudinal axis; and a support member having distal and proximal ends, wherein the support member includes a longitudinally extending slot disposed between the distal and proximal ends of the support member, the slot having opposing ends, wherein the slot is configured to pass an elongate anchor such that the elongate anchor is slidable between the first end and the second end of the slot.

Abstract: A disc replacement device including a first body member with a convex articulation surface and a second body member with a concave articulation surface is disclosed. When operably positioned, the convex articulation surface engages the concave articulation surface to provide for movement therebetween. The disc replacement device also includes a first opening in the first body member and a second opening in the second body member, wherein the openings are angled and extends from the front aspects of the body members through the external surfaces. The disc replacement device further includes at least two bone fasteners for insertion into the first and second openings to secure the disc replacement device to a first and second vertebra. An interbody motion device and fusion implant, as well as a surgical method for implantation are also disclosed.

Abstract: A surgical fastener manipulation tool in accordance with embodiment of the present invention is useful by a surgeon to place fasteners such as threaded screws. The surgical fastener manipulation tool selectively engages a mating structure of fastener for securing the fastener thereto. Thus, advantageously, the surgical fastener manipulation tool can be used for placing such fasteners and/or can be used for extracting (i.e., removing) such fasteners. The ability to extract a fastener (e.g., a threaded bone screw) with the same tool used for placing it is highly beneficial due to time savings during a surgical procedure and is advantageous with respect to prior art fastener manipulation tool configurations that require placement and extraction tools to be differently configured.

Abstract: A bone plate locking cannula and drill guide assembly having a locking cannula detachably mountable onto screw-receiving apertures of a bone plate and a drill guide received within the locking cannula such that pilot holes are drilled through the apertures into bone at the proper angle to receive bone screws. The screw receiving apertures have a proximal bore of greater diameter than a distal bore, and the proximal bore is provided with internal threading to mate with external threading located on the distal end of the locking cannula. The bone screws are inserted through the locking cannula after removal of the drill guide and fastened into the bone to secure the bone plate in position without having to remove the locking cannulas from the bone plate, the internal diameter of the locking cannula bore being greater than the maximum diameter of the screw heads. The locking cannula is detached from the bone plate after the bone plate has been secured in place on the bone.

Abstract: Bone fixation apparatus and spinal implants are disclosed herein. The spinal implants including a body with a first end and a second end, a first attachment portion at the first end, wherein the first attachment portion includes a first opening with at least one lip, a second attachment portion at the second end, wherein the second attachment portion includes a second opening with at least one lip, and an intermediate portion connecting the first attachment portion and the second attachment portion. Surgical methods for inserting the bone fixation apparatus and spinal implants into a patient are also disclosed.

Abstract: The present invention discloses single level fusion systems and methods of use. The single level fusion systems include a first fastener, a second fastener, and a connector to secure the first fastener to the second fastener. The method of assembling a single level fusion system including obtaining a first fastener, a second fastener, and a connector, securing the first fastener to the connector, and securing the second fastener to the connector. Methods of using the single level fusion systems are also disclosed.

Abstract: An anterior cervical plate system is provided. The plate is configured to receive bone screws for attachment to and immobilization of adjacent vertebrae of the spine. The system includes a lock configured to prevent the bone screws from backing out of the plate. The lock includes at least one blocking surface that is movable between a blocked configuration preventing the bone screw from backing out and an unblocked configuration allowing passage of the bone screw. The lock achieves a blocked position in a rotation of less than 90 degrees while maintaining or increasing a low-profile.

Abstract: A spinal plate assembly comprising a base plate defining an opening adjacent at least one aperture for receiving a bone screw which attaches to a spinal vertebrae. The aperture includes a seat and an annular groove having an end wall. The assembly comprises a locking mechanism having a split ring partially recessed within the annular groove and moveable between a locked condition partially blocking the aperture for retaining the screw in the seat and an unlocked condition radially deformable into the annular groove for permitting screw removal. The split ring has a proximal end and a distal end. The distal end is configured to engage the end wall of the annular groove. The locking mechanism comprises a rotating member retained within the opening of the base plate and having a notch configured to engage the proximal end of the ring to drive the ring toward the unlocked condition.

Abstract: A modular anchor bone fusion cage is provided. The cage includes a spacer configured to fit into a space between the faces of two bones that are to be fused together. A fusion plate having at least a main body portion is coupled to the spacer. Fasteners extend through the fusion plate to engage the bone. At least some of the fasteners also extend through the spacer to engage the opposed faces of the bone.

Abstract: A method and apparatus is provided for use in spinal fusion procedures. An interbody fusion device has a first piece that is a load bearing device designed to bear the axial loading from the end plates of adjacent vertebrae. A second piece of the interbody fusion device is a retention device whose function is to prevent migration of the load bearing device. One or more fasteners secure the retention device to the vertebrae above and below the load bearing device. The fasteners cause the end plates of the vertebrae to compress the end plates to the load bearing device to facilitate proper fusion. The second piece can be configured to include lips that abut the apothyseal rings during, with the plate including bores angled such that fasteners penetrate the apothyseal rings.

Abstract: An anterior cervical plate system is provided. The plate is configured to receive bone screws for attachment to and immobilization of adjacent vertebrae of the spine. The system includes a lock configured to prevent the bone screws from backing out of the plate. The lock includes at least one blocking surface that is movable between a blocked configuration preventing the bone screw from backing out and an unblocked configuration allowing passage of the bone screw. The lock achieves a blocked position in a rotation of less than 90 degrees while maintaining or increasing a low-profile.

Abstract: A modular anchor bone fusion cage is provided. The cage includes a spacer configured to fit into a space between the faces of two bones that are to be fused together. A fusion plate having at least a main body portion is coupled to the spacer by a connector. Fasteners extend through the fusion plate to engage the bone. At least some of the fasteners also extend through the spacer to engage the opposed faces of the bone. A cover plate is coupled to the fusion plate to inhibit the fasteners from backing out prior to fusion of the bones.

Abstract: Anterior cervical instrumentation systems, methods, and devices are disclosed. Systems may facilitate immobilizing or providing support for the cervical portion of the vertebral column of a patient. A device may comprise a plate having two channels located in a proximal to distal direction, and may further comprise at least one aperture. The device may further comprise attachment elements such as attachment cross-links and spacer cross-links, and fasteners. The plate and the attachment elements may be secured to the vertebrae by passing fasteners through apertures and channels. The length of the plate, position and number of the attachment cross-links, position and number of spacer cross-links and degree of movement may be intraoperatively selected by the surgeon to provide an optimal application and procedural outcome. Uniform components of the devices and systems allow for a more streamlined and simplified method of treating spinal conditions.

Abstract: A bone fixation plate includes a first opening formed in a plate that is configured to receive a first fastener; a second opening formed in the plate that is configured to receives a second fastener, and a retention member that extends into a third opening formed in the plate between the first opening and the second opening, wherein the retention member is elastically deformable between at least three positions.

Abstract: Embodiments provide methods, apparatuses, and systems for fixation of a fractured bone. In various embodiments, the systems and plates may provide elastic suspension of the receiving holes relative to the osteosynthesis plate. This elastic suspension may promote load distribution between the screws that connect a bone segment to the plate, thereby reducing stress risers and load shielding effect. In addition, stress at the screw holes, and within the construct as a whole, is reduced by incorporation of these elastic elements in the plate. Additionally, in some embodiments, for instance if fracture healing by callus formation is desired, elastic suspension of the receiving holes relative to the osteosynthesis plate may enable small, controlled amounts of relative motion between bone fragments connected by the plate, which may promote fracture healing by callus formation.

Abstract: A bone plate screw-blocking system and method that comprises a plate with at least two bone screw receiving holes, blocking elements, bone screws, and a tool capable of simultaneously actuating at least two blocking elements. The plate includes an upper surface and a lower surface with bone screw receiving holes that extend through both surfaces of the plate. The bone screws couple the plate to the bone via the bone screw receiving holes. The blocking elements are movably positioned proximate each bone screw receiving hole. In an initial unblocked position, the blocking elements do not cover the bone screw receiving holes. Upon movement into final blocked positions, the blocking elements cover at least a portion of the bone screw receiving holes and preferably extend over at least a portion of the bone screw during use.

Abstract: An implant has a bone plate with a bone contacting surface and an opposite outwardly facing surface. The plate includes a split-ring receiving recess open to the outwardly facing surface located intermediate first and second bone screw receiving openings in the plate. The first and second bone screw receiving openings each having a slot spaced from the outwardly facing surface towards the bone contacting surface. The slot is formed in a wall of the first and second bone screw receiving openings. The slot is open to the split ring receiving recess. A resilient split-ring has a thickness less than a height of the slots in the first and second bone screw openings when measured along the bone screw receiving opening axis.

Abstract: The present invention relates to a surgical drill guide having an anchoring mechanism for locking the drill guide to a bone plate. The anchoring mechanism is adapted to be received through an opening of a bone plate and rotated to lock the drill guide to the bone plate. The anchoring mechanism can be rotated by a driver, which has a distal end key that fits into a corresponding socket of on the proximal portion of the anchoring mechanism. The present invention also relates to a kit including a bone plate, a driver, and the drill guide and a method for using the kit to perform surgery.

Abstract: Embodiments of bony region stabilization are described generally herein. Other embodiments may be described and claimed.

Abstract: A bone plate having at least one screw hole adapted to receive a bone screw, a blocker having a blocking end for blocking a bone screw from further backout of bone the blocker being predisposed in a blocking position wherein the blocking end at least partially overlaps a portion of the screw hole, the blocker being moveable from the blocking position by contact with the bone screw during insertion of the bone screw into the screw hole, and a blocker fixation element having an open orientation at which the blocker can move from the blocking position and a closed orientation preventing substantial movement of the blocker from the blocking position. The blocker fixation element cannot be moved to the closed orientation unless the screw head passes the blocker, thereby revealing that the blocker fixation element is in position to prevent substantial movement of the blocker.

Abstract: The present invention relates generally to medical devices and methods for use in spinal surgery. In particular, the disclosed devices relate to a spinal fixation system and an intervertebral spinal implant assembly sized and dimensioned for the lumbar spine implantable via an anterior or anterolateral approach. The devices include an implant, bone screws, and an improved locking mechanism to prevent the back out of screws.

Abstract: A retaining mechanism for use in affixing a stratum to bone is disclosed. The mechanism comprises a stratum comprising a first surface, a second surface, and a hole extending between the two surfaces. The hole has a central longitudinal axis extending substantially perpendicular to the two surfaces. The retaining element comprises a first position that permits a fastener to be passed through the hole, a second position that at least partially overlaps the hole, and a spring element. The spring element is configured to engage the stratum, configured to move in a direction substantially perpendicular to the central longitudinal axis of the hole when the retaining element moves between its first and second positions, and configured to engage the retaining element to help maintain the retaining element in its second position to help prevent inadvertent backing out of the fastener after it has been fully inserted into the hole.

Abstract: In an exemplary embodiment, the present invention provides an orthopedic plating assembly for bone fixation that includes an orthopedic plate and orthopedic anchors that can accommodate subsidence in the vertebral bodies as well as prevent the anchors from “backing out” of their installed position. The assembly, in one embodiment, includes an orthopedic plate and at least one orthopedic anchor, the orthopedic anchor capable of rotating and translating with respect to the plate. The assembly further includes a first blocking member and a second blocking member, the blocking members cooperate to prevent the at least one orthopedic anchor from uninstalling from an installed position.

Abstract: A cervical plate assembly facilitates the fusion of cervical vertebrae by quickly and easily causing the vertebrae to exert a preloading force against a bone graft interposed therebetween. A cervical plate assembly also facilitates the installation of the cervical plate assembly in an orthopedic surgical procedure by providing both a locking mechanism that positively retains one or more fasteners thereto and a viewing window that results in an unobstructed view of the vertebrae and the bone graft.

Abstract: A bone repair system, kit and method for percutaneous repair of a bone segment containing a first bone segment and a second bone segment in a patient, each bone segment having a drill hole. The system comprises a longitudinal member configured to contact the first bone segment and the second bone segment and having at least one opening and cleats on the side adapted to contact the first bone segment and the second bone segment; a first fastener assembly configured to be disposed through the opening of the longitudinal member to hold the longitudinal member in place through the opening and the hole in the first bone segment; and a second fastener assembly configured to be disposed through the opening of the longitudinal member to hold the longitudinal member in place through the opening and the hole in the second bone segment.

Abstract: Embodiments of bony region stabilization are described generally herein. Other embodiments may be described and claimed.

Abstract: A spinal implant for stabilizing first and second vertebrae. The spinal implant includes an intervertebral spacer and a bone stabilization member configured to be coupled to the intervertebral spacer. The bone stabilization member includes a plurality of bone screw openings and a plurality of bone screws extendable through the bone screw openings to secure the bone stabilization member to the vertebrae. A retention member, which is slidably coupled to the bone stabilization member, is linearly slidable between a first position and a second position while coupled to the bone stabilization member. In the first position, each of the bone screws is permitted to be inserted into the bone screw openings, and in the second position the retention member at least partially covers each of the bone screw openings to prevent a bone screw from backing out of the respective bone screw opening.

Abstract: A locking element is configured to be used with a polyaxial bone anchor, and is substantially cylindrical with a bottom side facing a head of the bone anchor, a top side opposite to the bottom side, and a surface portion with an external thread. The locking element has a first recess at the bottom side for accommodating at least a portion of the head, and a second recess at the top side for engagement with a driver. The second recess is located outside the center of the top side. The head has a portion with a largest diameter, and a first level L1 is defined by the highest point of a circle with the largest diameter drawn around the head, and a second level L2 is defined by the bottom of the second recess, L2 being at a level not higher than L1.

Abstract: An improved insert for assembly with a bone plate is described. The insert has a first opening adapted to receive a set screw and a second opening adapted to receive a bone screw. The insert is connectable to the bone plate using a set screw. The insert in conjunction with the set screw provides an improved range of relative motion for placing the bone screw at outboard locations with respect to the bone plate. That way, bone fragments that are not necessarily reachable using the bone plate without the insert can be secured together for improved healing.

Abstract: A cervical plate having backout or reverse threading protection is provided. The cervical plate has one screw bores through which at least one screw extends to anchor the cervical plate to a vertebra. The plate further has at least one channel with at least one engaging edge. A cover plate has a cover plate that extends over a portion of a screw head of the screw. The cover plate also has a locking extension with at least one locking edge at a distal end. The locking extension is inserted into the channel such that the engaging edge and the locking edge engage and hold the cover plate such that the cover plate edge is substantially adjacent the portion of the screw head preventing the screw from backing out.

Abstract: A spinal plate system includes a screw, spinal plate and cap. A head of the screw includes a portion of a first sphere that has a first center and a portion of a second sphere that has a second center approximately concentric with the first center. A body of the screw extends from the first sphere. The spinal plate includes an opening through the spinal plate and an associated recess in the spinal plate that is eccentric with the opening. The cap includes an alignment opening and is configured to be rotationally engaged in the recess between a first rotational configuration and a second rotational configuration. In the first rotational configuration, the body threads into a vertebra in a selected trajectory through the alignment opening and the opening in the spinal plate and the head engages at least a portion of the opening in the selected trajectory.

Abstract: A system for performing surgical repair of the spine includes a distractor and a permanently implanted bone plate system. A surgical repair methodology is also disclosed that employs an implanted bone plate system with a substantially void internal volume which is attached to adjacent vertebrae subsequent to the distraction and adjustment of curvature of the vertebrae and prior to the excision of disc and/or end plate tissue through the bone plate. The device further facilitates the subsequent delivery of an interbody repair device for the purpose of either fusion or dynamic stabilization, such as by disc arthroplasty. The plate may be permanently implanted, such as when a fusion between the attached vertebral bodies is desired, but it need not be permanently implanted.

Abstract: A receiving member has a primary socket for a fixation mechanism and a secondary socket for a locking device. The secondary socket has a first bore intersecting a portion of the primary socket and forming an arcuate cut-out. The secondary socket has a chord member extending into the secondary socket first bore that forms a radial undercut in the secondary socket. The secondary socket has a detent extending from the radial undercut into the chord member. The locking device is rotatable in the secondary socket between an unlocked position in which an engagement surface of a cap of the locking device is angularly displaced from the arcuate cut-out, and a locked position in which the cap engagement surface occupies the arcuate cut-out and engages the fixation mechanism, and the arm engages an underside of the chord member, thereby preventing the fixation member from disengaging the receiving member primary socket.