A keel for an orthopedic implant with a tray portion. The keel has a wall having a posterior end, an anterior end, and sides that extend from a surface of the tray portion. The wall is at least partially upraised away from the surface of the tray portion at its posterior end to define a posterior keel opening. The anterior end may either merge with the surface of the tray portion or can be spaced away to form an anterior keel opening. The keel can slant downwardly from the posterior end to the anterior end by about 10 to 20 degrees. The wall can have two spaced apart flat side walls and a flat top wall, or can be a continuous curved wall. A bone ingrowth space is defined between the wall and the tray portion. Openings can optionally be formed in the wall for additional bone ingrowth.

An intervertebral disc is provided having an upper plate, a lower plate, and a core. The upper and lower plates include outer vertebral body contacting surfaces which are provided with attachment enhancing features to ensure bone integration. The attachment enhancing features shown include one or more fins, serrations and teeth. An opposite surface of the plates from the vertebral body contacting surfaces is formed with a recess which serves as a bearing surface for the core. In order to form an intervertebral disc with a lower disc height, at least one of the recesses is provided opposite a corresponding dome shaped portion on the vertebral body contacting surfaces. This allows the plates to be formed with a thinner profile for a smaller overall disc height. In addition to providing a lower overall height to the artificial disc, the dome shaped portion of the plates also provides a more anatomically shaped outer vertebral body contacting surface.

An intervertebral implant component of an intervertebral implant includes an outer surface for engaging an adjacent vertebra and an inner surface. A keel extends from the outer surface and is designed to be disposed in a slot provided in the adjacent vertebra. This keel extends in a plane which is non-perpendicular to the outer surface; and preferably there are two of the keels extending from the outer surface which are preferably offset laterally from one another. In another embodiment, an anterior shelf is provided at an anterior end of the outer surface, and this anterior shelf extends vertically away from the inner surface in order to help prevent bone growth from the adjacent vertebra towards the inner surface. Further in accordance with disclosed embodiments, various materials, shapes and forms of construction of the component and/or keel provide various benefits.

Arthroplasty components include an articular surface and a bone-facing surface. The bone-facing surface bears at least one anchoring element adapted for an oblique implantation trajectory. The anchoring element includes a reinforcement plate, a dowel, and surface features. Each surface feature resists forces acting along a different direction.

Arthroplasty components include an articular surface and a bone-facing surface. The bone-facing surface bears at least one anchoring element adapted for an oblique implantation trajectory. The articular surface includes a larger radius of curvature in the superior-inferior direction than in the anterior-posterior direction. An inferior chamfer may be present on the articular surface. Instruments and implantation methods are also disclosed.

A prosthesis may include a stem, a ball stud, an adaptor, and a head. The stem may include a longitudinal axis and a bore having a central axis that is angled relative to the longitudinal axis. The ball stud may include a cylindrical shaft and a ball end. The cylindrical shaft may be received in the bore of the stem. The adaptor may include a tapered outer surface and a ball socket rotatably receiving the ball end of the stud. The head may be rotatably supported by the adaptor and may include a semispherical articulating surface and a female taper rotatably receiving the tapered outer surface of the adaptor.

An intervertebral disc is provided having an upper plate, a lower plate, and a core. The upper and lower plates include outer vertebral body contacting surfaces which are provided with attachment enhancing features to ensure bone integration. The attachment enhancing features shown include one or more fins, serrations and teeth. An opposite surface of the plates from the vertebral body contacting surfaces is formed with a recess which serves as a bearing surface for the core. In order to form an intervertebral disc with a lower disc height, at least one of the recesses is provided opposite a corresponding dome shaped portion on the vertebral body contacting surfaces. This allows the plates to be formed with a thinner profile for a smaller overall disc height. In addition to providing a lower overall height to the artificial disc, the dome shaped portion of the plates also provides a more anatomically shaped outer vertebral body contacting surface.

A prosthesis may include a stem, a ball stud, an adaptor, and a head. The stem may include a longitudinal axis and a bore having a central axis that is angled relative to the longitudinal axis. The ball stud may include a cylindrical shaft and a ball end. The cylindrical shaft may be received in the bore of the stem. The adaptor may include a tapered outer surface and a ball socket rotatably receiving the ball end of the stud. The head may be rotatably supported by the adaptor and may include a semispherical articulating surface and a female taper rotatably receiving the tapered outer surface of the adaptor.

An intervertebral disc is provided having an upper plate, a lower plate, and a core. The upper and lower plates include outer vertebral body contacting surfaces which are provided with attachment enhancing features to ensure bone integration. The attachment enhancing features shown include one or more fins, serrations and teeth. An opposite surface of the plates from the vertebral body contacting surfaces is formed with a recess which serves as a bearing surface for the core. In order to form an intervertebral disc with a lower disc height, at least one of the recesses is provided opposite a corresponding dome shaped portion on the vertebral body contacting surfaces. This allows the plates to be formed with a thinner profile for a smaller overall disc height. In addition to providing a lower overall height to the artificial disc, the dome shaped portion of the plates also provides a more anatomically shaped outer vertebral body contacting surface.