Shoulder joint prosthesis
AssigneeCenterpulse Orthopedics Ltd.
InventorsMarkus Rauscher, Peter Wendt
Life of this patent
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Abstract
A shoulder joint prosthesis is shown having two bearing bodies (1, 2; 11, 12) which slide on one another and which can be respectively connected to the upper arm (3) by a shaft (5) and to the shoulder bone (4) by a platform (6). When the connection to the shaft (5) is brought about by a non-rotationally symmetrical, conical body (7) with a self-locking seat, with its periphery (8) being form matched to a mating shape (15) in the shaft (5) which is rotationally fixed relative to a longitudinal axis (9) arid keyed by the taper so that the connection is releasable and repeatedly fixable in the same angular position, large forces can be transmitted by the connection.
Claims9
A shoulder joint prosthesis having two bearing bodies (1, 2;
- 11, 12) which slide on one another and which can be respectively connected to an upper arm (3) by a shaft (5) and to a shoulder bone (4) by a platform (6), wherein connection of the prosthesis to the shaft (5) is brought about by a non-rotationally symmetrical, conical body (7) with a self-locking seat, with a periphery (8) of said conical body being form matched to a mating recess (15) in the shaft (5) which is rotationally fixed relative to a longitudinal axis (9) and keyed by an amount of taper so that connection of the prosthesis to the shaft (5) is releasable and repeatedly fixable in a predetermined angular position;
- wherein a bearing shell (2) is secured to the platform (6) and a bearing head (1) to the shaft (5);
- wherein the bearing head (1) has a spherical recess (19) therein and is connected to the conical body (7) via a fixable ball joint;
- and
- wherein a longitudinally slit (21) ball (23) is formed on the conical body (7), the ball having a conical bore (24) with a conical pressure member (25) received in the conical bore (24);
- and the conical body (7) having a threaded bore (29) adjacent to the conical bore (24) and a screw (27) received in the threaded bore (29) adapted to act on the conical pressure member (25) in order to spread apart the ball (23) and to fix the ball in the spherical recess (19) of the bearing head (1).
A shoulder joint prosthesis having two bearing bodies (1, 2;
- 11, 12) which slide on one another and which can be respectively connected to an upper arm (3) by a shaft (5) and to a shoulder bone (4) by a platform (6), wherein connection of the prosthesis to the shaft (5) is brought about by a non-rotationally symmetrical, conical body (7) with a self-locking seat, with a periphery (8) of said conical body being form matched to a mating recess (15) in the shaft (5) which is rotationally fixed relative to a longitudinal axis (9) and keyed by an amount of taper so that connection of the prosthesis to the shaft (5) is releasable and repeatedly fixable in a predetermined angular position;
- wherein a bearing shell (2) is secured to the platform (6) and a bearing head (1) to the shaft (5);
- wherein the bearing head (1) has a spherical recess (19) therein and is connected to the conical body (7) via a fixable ball joint;
- and
- wherein the conical body (7) has an additional circular cone (17), onto which a spreadable ball body (18) can be placed in a self locking manner, and which circular cone (17) is adapted, when driven into the spreadable ball body (18), to clamp the spreadable ball body (18) in the spherical recess (19) of the bearing head (1).
Dependencies are inferred from the claim text.