Forty-three procedures on the proximal interphalangeal joint in 24 patients are retrospectively reviewed. A diagnosis of erosive osteoarthritis accounted for 83% of the joints that had operation. Flexible silicone interposition, cemented Biomeric arthroplasty, or arthrodesis were done based on the individual functional needs of each patient and involved digit. All cemented Biomeric devices, preferentially implanted in the radial digits for optimal lateral stability, failed through the elastomer hinge at an average of 2.25 years after operation. Arthrodesis of the proximal interphalangeal joint in the radial digits provided greatest improvement in lateral pinch strength. Flexible silicone interposition arthroplasty in the ulnar digits provided an average flexion arc of 56 degrees with satisfactory pain relief. Although none required revision, radiographically evident bone resorption adjacent to the silicone implant was progressive over time; 35% of implants followed-up longer than 2 years demonstrated periarticular erosion and 20% followed-up beyond 4 years had extensive endosteal resorption along the intramedullary prosthetic stems. Surgical treatment of the osteoarthritic proximal interphalangeal joint remains an unsolved problem.