Abstract: An interpositional biarticular disk implant (11) having a circular peripheral rim, a generally toroidal axial center opening (13) and convex upper and lower surfaces (15, 17) is implanted between resected concave surfaces of the metacarpal base and the trapezium or other carpal bone in a CMC joint replacement. The disk (11) is anchored in operative position through the use of a flexible cord, such as a harvested tendon that passes through the center opening (13) and through osseous passageways created in the two facing bones.

Abstract: Hemi joint replacements for the base of the first metacarpal of the CMC joint are provided which can effectively restore and reestablish functional joint mechanics while preserving the soft tissues that contribute to joint stability and function. The implants have a unique head shape with a saddle-like articular surface that is shaped somewhat similar to a conventional bicycle seat. A set of four proportionately larger and smaller implants allows a surgeon to choose the appropriately sized prosthesis for implantation in respect of the metacarpal osteotomy.

Abstract: The present invention provides an orthopedic device assembly comprising a first assembly element, a second assembly element, and a retaining mechanism. The first assembly element has a recess that receives the second assembly element, and the retaining mechanism holds the second element in an assembled state with the first assembly element. The retaining mechanism includes a retaining member with an angular cross-section defined by a base portion and a lateral flange portion projecting from the base portion. The retaining member is inserted through an aperture of the first assembly element into a groove in a wall of the recess of the first assembly element, with the flange portion projecting laterally of the groove and overhanging a shoulder portion of the second assembly element so as to retain the second assembly element in the assembled state with the first assembly element.

Abstract: A joint surface replacement or joint prosthesis for the distal radioulnar (DRU) joint. A complete surface replacement comprises two parts, a radial component (1) and an ulnar component (2), both of which are designed to be inserted radially relative the radius (6) and the ulna (7). The radial (1) and ulnar (2) components are constructed to assure that the concave surface of the radial component may be pivoted and translated around the convex surface of the ulnar component during rotational movement of the forearm. Either component may be singularly implanted when there is no deterioration of the mating component. By providing these components in a range of thicknesses and lengths, more effective stabilization of such joint is possible.

Abstract: First and second elements that have mating heads form an interphalangeal joint prosthesis that allows smooth articulation dorsal to volar. The first element head has a proximal surface defined by two intersecting planes, a stem portion that extends longitudinally therefrom and a convex bicondylar articulating surface having a central valley. The second element has a biconcave articulating proximal surface which mates with the first element articulating surface and a stem portion that extends longitudinally from the distal surface thereof, with a notch being formed in a dorsal surface of the head at a location that does not disturb attachments to the dorsal tubercle or the function of the median band of the extensor expansion. Sets of such joint prostheses of varying sizes are provided which are designed so that adjacent sizes interfit. A method for treating a deteriorated PIP joint is described.

Abstract: A joint surface replacement or joint prosthesis for the distal radioulnar (DRU) joint. A complete surface replacement comprises two parts, a radial component (1) and an ulnar component (2), both of which are designed to be inserted radially relative the radius (6) and the ulna (7). The radial (1) and ulnar (2) components are constructed to assure that the concave surface of the radial component may be pivoted and translated around the convex surface of the ulnar component during rotational movement of the forearm. Either component may be singularly implanted when there is no deterioration of the mating component. By providing these components in a range of thicknesses and lengths, more effective stabilization of such joint is possible.

Abstract: First and second elements that have mating heads form an interphalangeal joint prosthesis that allows smooth articulation dorsal to volar. The first element head has a proximal surface defined by two intersecting planes, a stem portion that extends longitudinally therefrom and a convex bicondylar articulating surface having a central valley. The second element has a biconcave articulating proximal surface which mates with the first element articulating surface and a stem portion that extends longitudinally from the distal surface thereof, with a notch being formed in a dorsal surface of the head at a location that does not disturb attachments to the dorsal tubercle or the function of the median band of the extensor expansion. Sets of such joint prostheses of varying sizes are provided which are designed so that adjacent sizes interfit. A method for treating a deteriorated PIP joint is described.

Abstract: Asymmetric and axisymmetric prostheses for replacement of the radial head are shown which are designed to smoothly interengage with the annular ligament of the radius and effectively allow a patient to recover normal functioning of the forearm. These prostheses have head, collar and stem sections, and the undersurface of the head which surrounds the collar provides a shoulder which is excellently gripped by the annular ligament through which the prosthesis is inserted during implantation, assuring achievement of the desired juxtaposition between the periphery of the prosthesis head and the radial notch of the ulna. In the asymmetric embodiment, shaping the head to provide a proximal surface of generally oval cross-section having an offset concave surface and a medial region of greater thickness offers particular advantages.

Abstract: A joint prosthesis for replacement of the metacarpal-phalangeal (MP) joint (19) of a human finger which includes a metacarpal element (13) with a stem (15) for reception into the medullary cavity of the metacarpal bone (11) and a generally ball-shaped articular head (17) and a phalangeal element (14) with a stem (16) for reception into the medullary cavity of the proximal phalangeal bone (12) and a generally socket-shaped head (18) which conforms to the ball-shaped head (17). The metacarpal element (13)'s articular head (17) has reliefs (51,52) located on each of its two lateral sides so as to provide a generally free path for the collateral ligaments (43,44). The phalangeal element (14)'s articular head (18) has a dorsal protrusion (71) that resists subluxation-dislocation of the phalangeal bone (12) and grooves (31,32) in its concave surface (22) which allow biological fluids access to the inner regions of the articulation contact surfaces (21,22).

Abstract: A joint prosthesis for replacement of the metacarpal-phalangeal (MP) joint of a human finger which includes a metacarpal element with a stem for reception into the medullary cavity of the metacarpal bone and a generally ball-shaped articular head and a phalangeal element with a stem for reception into the medullary cavity of the proximal phalangeal bone and a generally socket-shaped head which conforms to the ball-shaped head. The metacarpal element's articular head has reliefs located on each of its two lateral sides so as to provide a generally free path for the collateral ligaments. The phalangeal element's articular head has a dorsal protrusion, that resists subluxation-dislocation of the phalangeal bone, and grooves in its concave surface which allow biological fluids access to the inner regions of the articulation contact surfaces.