A tibial knee joint prosthesis for attachment to a suitably prepared tibial bone, providing bearing portions in the lateral and medial compartments. The lateral and medial bearing surfaces of the component are inclined at different angles in the anterior to posterior direction of the knee, so that when mounted to the tibia, the lateral bearing surface of the prosthesis is higher than the medial bearing surface to the posterior side of the knee. In this way the lateral ligament is tightened progressively more than the medial ligament as the knee moves from extension to flexion, resulting in increased stability in the lateral compartment.

A prosthesis suited for orthopedic implantation possesses a multi-piece stem component that supports an artificial joint surface that can articulate with another artificial joint surface in various ways. The prosthesis can be assembled in a snap fit and/or interlocking fashion that provides positive locking means without the use of screws or other fasteners. The prosthesis can accommodate fitment of a plastic joint surface made, e.g., from ultra high molecular weight polyethylene. The prosthesis is well suited for use in an ankle replacement system that can be installed using minimally invasive intramedullary guidance established with respect to the major axis of the tibia by minimally invasive access through the calcaneus, through an incision in the bottom of the foot. The prosthesis makes possible the installation of a total ankle system using minimally invasive anterior access to the ankle joint for making bony cuts and to install prosthesis components.

A hemi-arthroplasty bone joint implant has a first part (120) with a stem (111) tor intramedullary implanting into a metacarpal, and a second part (110) to engage the trapezium is a translational manner, a hemi-arthroplasty articulating coupling (121). This allows multi-axial motion with translational movement of the second part over the trapezium and rotation of the first part (110) about the articulating coupling (121, 103). There is also a converter to convert the implant to a toral arthroplasty implant in situ during revision surgery. The second part (110) and the hemi-arthroplasty coupling (100, 123, 121) are removable in situ during revision surgery. The first part (120) has an engagement threaded socket (117) for, after removal of the second part and the hemi-arthroplasty coupling, engaging the replacement coupling (200) and allowing mutual articulation of the first (120) and replacement parts (220). This forms a total arthroplasty joint implant.

A glenoid component is provided to reduce glenoid loosening when implanted in orthopedic joint replacement/reconstruction, such for a shoulder. The glenoid component can include pegs or a keel and articulating surface geometry that uses complex, non-spherical geometry to recreate a level of constraint that is adequate, but not excessive, to thereby mitigate loosening of the glenoid component after implantation. In addition, some embodiments provide that peak stresses both within cement and at an interface of the cement and a supportive component can be reduced. Further, geometry of the pegs can allow stresses to be evenly applied to a cement mantle formed in the supportive component. Finally, the pegs can be configured to desired lengths in order to avoid placement in areas of the supportive component, for example, that have insufficient bone stock.

An artificial joint is characterized by: having a first member including a caput part on which a prescribed curved surface is formed, and a second member including a fossa part having a surface which abuts the prescribed curved surface of the caput part; the second member being rotatable in a flexing direction of a joint with a prescribed point on the caput part being the center of rotation; and the prescribed curved surface of the caput part being defined by a curve which depicts a convex arc toward the side abutting the fossa part when the caput part is viewed from the axial direction of the rotation, and in which, when two arbitrary points are taken on the curve, the radius of curvature of the point positioned further toward the flexing side of the joint on the curve is smaller than the radius of curvature of the other point.

Bone-sparing hip resurfacing surgery using only an acetabular component in which the femoral head articulates, being only shaved to a spherical shape and cleared of osteophytes that could impinge on the acetabulum and so restrict the range of motion. The inner surface of the resurfacing cup is aspherical in shape creating an annular contact with the femoral head. The inner, articulating surface of the cup is ADLC or pyrolytic carbon coated to reduce friction and wear of the femoral head. The surgical approach significantly reduces surgery time by avoiding the use of the femoral resurfacing component. The cup is preferably of the double-shell type for cementless fixation, but it can also be made as a single shell for cementless or cemented fixation. Should a revision surgery due to wear of the femoral head become necessary, the cup can be retained and combined with a dual mobility femoral component.

Expandable spinal implants, systems and methods are disclosed. An expandable spinal implant may include a first endplate, a second endplate, and a moving mechanism that is operably coupled to the first and second endplates. The moving mechanism may include a wedge, a first sliding frame and a second sliding frame disposed on opposite sides of the wedge, a screw guide housing a rotatable first set screw and a rotatable second set screw opposite the first set screw. The first set screw may be operably coupled to the second sliding frame and the second set screw may be operably coupled to the wedge. The moving mechanism may operably adjust a spacing between the first and second endplates upon simultaneous rotation of the first and second set screws and operably adjust an angle of inclination between the first and second endplates upon translating the first set screw or second set screw.

Expandable spinal implants, systems and methods are disclosed. An expandable spinal implant may include a first endplate, a second endplate, and a moving mechanism that is operably coupled to the first and second endplates. The moving mechanism may include a wedge, a first sliding frame and a second sliding frame disposed on opposite sides of the wedge, a screw guide housing a rotatable first set screw and a rotatable second set screw opposite the first set screw. The first set screw may be operably coupled to the second sliding frame and the second set screw may be operably coupled to the wedge. The moving mechanism may operably adjust a spacing between the first and second endplates upon simultaneous rotation of the first and second set screws and operably adjust an angle of inclination between the first and second endplates upon translating the first set screw or second set screw.