Implant arthroplasty of the hand : retrospective and prospective considerations

摘要: Small joint arthroplasty has lagged behind the development of that in large joints because their small sizes, different shapes, presence within kinetic chains, complex soft tissue investments, adjacent rays, secondary displacement and contracture, differing requirements degenerative rheumatoid arthritis. Prosthetic must take into consideration range motion, stability, tendon moment arms, fixation, ease implantation, blocompatibility, wear strength characteristics, reconstruction. The metacarpophalangeal, interphalangeal, trapeziometacarpal each present problems design kinematic equivalent prostheses. One-piece polymeric designs have advantages cost, adaptability, known performance but show degradation function with time. Total potential better simulating normal shown tendencies to subsidence, loosening, breakage. rigidity hinge limits damping out-of-plane forces places greater stress on bone-stem interfaces, whereas global poor constraint features.