Patent ID: 6454808
Filing Date: 2002-09-24
Classification: A61F

Abstract:
A finger joint prosthesis, comprising stems embeddable into tubular bones at a remotely disposed portion and a nearly disposed portion of a finger joint stems (11, 21); a socket (1) having an opening (12) at one portion and a spherical face (10) at an inner side and being integrally formed with one of the stems (11) on a side opposed to the opening (12); a head (2) having a spherical portion (20) to be fitted to the spherical face (10) and being integrally formed with the other of the stems (21) extending outwardly from the opening (10); a sheath (3) surrounding either of the stem (11) of the socket (1) and the stem (21) of the head (2), wherein at least half of a length of the sheath (3) and the stem (11, 21) orthogonal to an axial direction is non-circular, the stems (11, 21) being movable slideably in an axial direction by adhering and fixing the sheath (3) to a narrow cavity at the nearly disposed portion or the remotely disposed portion, the opening (12) being formed as a long hole having an inclined face (120) at an edge portion, the stem (21) of the head (20) having a projected trapezoidal portion (23) at a boundary between the stem (21) of the head (2) and the spherical portion (20), the projected trapezoidal portion (23) having a conical side wall face (230) at a side face and a side flexing angle is restricted by bringing the conical side wall face (230) into contact with the inclined face (120).