US 5,702,471 A · Finger joint

Abstract

A finger joint has first and second hollow anchorage shafts (2, 3) which can be implanted in finger tubular bones with a hinge joint (4) arranged between them. The first hollow shaft (2) can be connected with a ball cage (5) of the hinge joint (4) in which a spherical part (6) is mounted, on which a protruding stem (7) is formed. This stem (7) passes through the ball cage (5), and indeed through a slit (8) provided therefor in the wall of the ball cage (5). The slit (8) in the ball cage (5) widens continuously from the point (P) at which the stem (7) passes through the ball cage (5) in the extended position of the joint (4) to the point (M) at which the stem (7) passes through the ball cage (5) in the flexed position of the joint. In this manner, additional play is allowed to the joint in the flexed position, which largely corresponds to the physiological coordinated movement of a finger joint.

Claims8

Dependent claims

A prosthetic finger joint (1) comprising a first and a second hollow anchorage shaft (2, 3) configured to be implanted in tubular finger bones, and a hinge joint (4) in a form of a ball-and-socket joint arranged between the shafts (2,3), the first hollow shaft (2) being connected with a ball cage (5) of the hinge joint (4), a spherical part (6) provided with a protruding stem (7) being mounted in the ball cage, the stem (7) passing through a slit (8) in the ball cage (5) and connecting with the second hollow shaft (3), the slit (8) in the ball cage (5) continuously widening from a point (P) at which the stem (7) passes through the ball cage (5) in an extended position of the joint (4) to a point (M) at which the stem (7) passes through the ball cage (5) in a flexed position of the joint (4).

Dependencies are inferred from the claim text.

Finger joint

Life of this patent

Finger joint

Life of this patent

Abstract

Claims8