Prosthetic replacement of the proximal interphalangeal joint.

The first proximal interphalangeal joint (PIPJ) replacements were hinged devices allow-ing only single-axis motion. Newer implant arthroplasties of the PIPJ have anatomically designed proximal phalangeal and middle phalangeal components. Constrained devices have typically lead to failure at the hinge mechanism or the prosthetic bone interface. A need to create balanced forces across the joint was the rationale behind the semicon-strained PIPJ prosthesis, which uses an anatomic design. Limitations of the silicone PIPJ implant include its lack of resistance to valgus loading at the index and long digits during the pinch maneuver. It is generally believed that a PIPJ surface replacement arthro-plasty that preserves the collateral ligaments will achieve greater PIPJ stability.