Proximal interphalangeal joint arthrodesis in a case of chronic proliferative osteoarthritis in the horse – a case report

Proximal interphalangeal joint (PIPJ) arthrodesis is performed commonly in horses with chronic osteoarthritis of the pastern joint or in cases of acute traumatic injury to the pastern, in which the weight-bearing bony column must be restored. Chronic osteoarthritis of the pastern joint is a frequent cause of lameness in the equine athlete and is evidenced by chronic lameness which is supported radiographically by periosteal proliferation and loss of joint space. The conventional method of joint fusion involves the opening of the joint, debridement of the joint cartilage, osteostixis of the subchondral bone plate and application of either lag screws or plate. This case report describes the successful treatment of chronic proliferative ossified osteoarthritis and periarthritis of the proximal interphalangeal joint of the front limb of two mares by performing simple percutaneous drilling destruction of the articular cartilage and stabilization with the application of three lag screws. After three years of conservative treatment with local corticosteroids, the mares exhibited non-weight-bearing lameness. Radiographs revealed extensive periarticular new bone formation over the proximal interphalangeal joint. Three 4.5 mm transcortical bone screws were placed in the lag fashion. A lower limb fiberglass cast was applied in both cases for 3 days. The antibiotic and analgesic protocol included gentamicin, penicillin, and flunixin meglumine for several days. Control radiographic examination after a period of 6 and 12 months showed reduction of the periarticular bone tissue. Both of the mares in this case study successfully returned to pleasure riding after undergoing forelimb arthrodesis.