Arthrodesis of the metacarpophalangeal and metatarsophalangeal joints to treat osteoarthritis in 17 horses.

Objective: To describe arthrodesis of the metacarpophalangeal (MCP) or metatarsophalangeal (MTP) joint with a locking compression plate (LCP) and a metallic tension band and report the outcome of horses treated for osteoarthritis (OA) with this technique.

Study Design: Retrospective case series.

Animals: Seventeen horses with OA of the MCP or MTP joint treated with arthrodesis.

Methods: Medical records (2004-2017) of horses treated for OA with arthrodesis of the MCP or MTP joint with an LCP and metallic tension band were reviewed. Preoperative variables included age, sex, breed, affected limb, and lameness grade. Surgical variables included implants used, surgery time, postoperative angle of joint, intraoperative complications, and anesthetic recovery method. Outcome was obtained from medical records and phone interviews.

Results: Lameness was scored as 4 out of 5 (range, 2-4) in 13 of 17 horses. All horses survived to discharge and were alive >6 months postoperatively, without any report of long-term complications. All horses were allowed unrestricted turnout, and 1 horse was lightly ridden. No postoperative infections or implant failures were reported. The only complications consisted of cast sores (n = 4).

Conclusion: Arthrodesis of the MCP/MTP joint was associated with acceptable morbidity and good long-term outcomes in these 17 horses with OA refractory to medical management.

Clinical Significance: The morbidity and prognosis after fetlock arthrodesis for OA seem more favorable than reported in horses treated with traumatic disruption of the suspensory apparatus.