Trapezo-metacarpal joint prosthesis for field of orthopedic surgery, has trapezium implant with spherical portion placed at end of rod, where portion has specific diameter and center of curvature situated at one millimeter above surface

摘要

The prosthesis has a trapezium implant (5) with a spherical portion (6) placed at an end of a threaded rod (7), where the portion has a flat rear surface (10) destined to rest against a trapezium bone. A metacarpal implant has a cap whose receptacle has a spherical surface corresponding to the spherical portion of the trapezium implant. The cup is placed at an end of the rod destined to be implanted in a medullary cavity of metacarpus. The spherical portion has a diameter of 8 millimeter and a center of curvature (9) situated on the rear surface or at 1 millimeter above the rear surface.