A spinal implant apparatus that is an expandable spacer including features to minimize or eliminate spacer cant or offset during and after completing the expansion process. The spacer includes a top component, a base component in engagement with the top component, and an expansion mechanism arranged to change the top component's position with respect to the base component. The mechanism for causing expansion may be a screw, a cam, a wedge or other form of distracting device. In one embodiment, the expandable spacer includes a base component with a set of towers and a top component with a set of corresponding silos, where the towers and silos are configured to minimize or eliminate tilt of the top component as it extends upwardly from the base component.

Intervertebral implants for implanting into an intervertebral space are provided. The implants can comprise one or more layers that are operably attached to one another. An implant can comprise a first layer having a first mating surface that mates with a second mating surface of a second layer. The first mating surface and the second mating surface can have features that allow them to complement each other. The implants can include one or more bore holes for receiving a fixation member. The bore holes can be horizontal, vertical or diagonal. In some cases, the bore holes will be blind bore holes.

A method and system for performing bone fusion and/or securing one or more bones, such as adjacent vertebra, are disclosed. The screws include a threaded tip connected to a main shaft and a threaded outer sleeve that rotates relative to the outer shaft until locked down. Independent rotation of the threaded outer sleeve relative to the threaded distal tip allows compression or distraction to modify the gap between the vertebral bodies. The screws are passed from the inferior to superior vertebra or superior to inferior, for example, through a trans-pedicular route to avoid neurological compromise. At the same time, the path of screw insertion is oriented to reach superior or inferior vertebra. An intervertebral cage of the system is configured for lateral expansion from a nearly straight configuration to form a large footprint in the disc space. The screws and cage may be combined for improved fixation with minimal invasiveness.

A spacer member is provided that is configured to be implanted adjacent an anatomical structure. The spacer member defines a curved bore, a first opening in a side wall of the spacer member and a second opening in one of a top wall and a bottom wall of the spacer member. Each of the first opening and the second opening are in fluid communication with the curved bore. A flexible anchoring member is configured to be inserted through the side opening and through the curved bore of the spacer member such that a distal end portion of the flexible anchoring member extends out of the second opening at an angle relative to the one of the top wall and the bottom wall of the spacer member.

A spinal bone graft includes one or more cortical bone portions forming a first unit. The first unit includes an engagement surface for contacting bone, and a mating surface. The mating surface forms at least one first undercut. The bone graft also includes one or more cortical bone portions forming a second unit. The second unit includes an engagement surface for contacting bone, and a mating surface. The mating surface forms either at least one second undercut, or at least one connector. In the former, at least one connector is received in each of the first and second undercuts to interconnect the first and second units. In the latter, the at least one connector of the second unit is received in the first undercut of the first unit to interconnect the first unit and second unit.

An artificial intervertebral disc is configured to be inserted between adjacent human vertebrae. The artificial intervertebral disc includes a first connection block, a joint block and a second connection block. The joint block has a convex surface and a rear surface. The rear surface of the joint block is stacked on the first connection block. The second connection block is slidably stacked on the convex surface of the joint block, such that the second connection block is movable relative to the first connection block. In addition, the convex surface is a curved surface, and the convex surface is arranged off-axis with respect to the rear surface.

An intervertebral disc prosthesis designed to be substituted for fibrocartilaginous discs ensures a connection between the vertebra of the vertebra column or the end of the latter. The prosthesis includes a pair of plates spaced from each other by a nucleus. The prosthesis has increased stability by providing the nucleus with a translation or rotation stop, or by inducing an angular correction between its plates contacting vertebra, or a combination of these characteristics. The stop includes parts external to the nucleus and contact surfaces perpendicular to their contact directions. Surgical methods and instrumentation for implanting the prosthesis are also described.

A prosthetic inserter includes an inserter head having at least first and second bosses, at least one of the bosses movable from a first position to a second position, that couple the inserter to a femoral provisional component via a pair of corresponding apertures, such as drill holes, within the articulating surfaces of a selected one of a series of femoral provisional components. Each provisional component of the series is capable of having different aperture distances measured between a respective pair of apertures. The bosses of the inserter are biased into an engagement position in which the inserter can be secured to a femoral provisional component to eliminate the need for an external engagement force to be supplied to the inserter.

A spinal interbody cage implant includes a cage, an endplate, and flexible barbs. The endplate is separately attached to the cage and is configured to receive, hold and direct a flexible barb into an upper vertebral surface and a flexible barb into a lower adjacent vertebral surface. Each proximal leg of the cage is configured to receive the endplate, and has a lateral bore that receives a pin which retains the endplate. The endplate directs a first flexible barb upwardly toward an upper vertebral surface, and directs a second flexible barb downwardly toward a lower vertebral surface. Each flexible barb has a proximal head, a shaft extending from the head with a bore extending from the head to its distal end. Teeth are provided along the exterior surface of the shaft with two flats disposed on opposite sides thereof with a slit extending from the distal end towards the head.

Techniques and systems for distracting a spinal disc space and supporting adjacent vertebrae are provided. Trial instruments are insertable into the disc space to determine a desired disc space height and to select a corresponding implant. Implants can be also be self-distracting and the implant providing the desired disc space height can be implanted in the spinal disc space.