JOHN C. JANICEK, DVM, MS, Diplomate ACVS 1 , JAMES L. COOK, DVM, PhD, Diplomate ACVS 1 , DAVID A. WILSON, DVM, MS, Diplomate ACVS 1 , and KARISSA M. KETZNER, DVM 1 1 Comparative Orthopaedic Laboratory, University of Missouri, Columbia, MO Veterinary Surgery January 2010 39 1 95 - 100 Objective—To adapt the multiple osteochondral autograft technique for treatment of a subchondral cystic lesion (SCL) of the proximal medial trochlear ridge (MTR) of the equine talus and assess long term outcome. Study Design—Case report. Animals—Quarter horse stallion with SCL of the proximal MTR of the talus. Methods—Osteochondral autograft techniques used in dogs and humans were adapted and optimized in equine cadavers. A horse with a SCL of the MTR of the talus was treated by osteochondral autografting. Three osteochondral autografts were harvested from the distal lateral trochlear ridge of the talus in the affected tarsus. No curettage or debridement of the osteochondral lesion was performed. Three recipient beds were predrilled and osteochondral autografts were press-fit into the proximal MTR of the talus. Outcome was assessed by radiography, telephone interview of the owner, and direct observation during training. Results—Postoperative radiographs indicated excellent filling of the osteochondral defect and graft-articular surface congruency. No complications were encountered after surgery. At 10 months after surgery, the horse successfully re-entered reining training, and continued to be sound and performing athletically 2 years after surgery. Conclusion—Osteochondral autografting deserves consideration and further evaluation as a primary treatment option for SCL of the proximal MTR of the talus in horses. Clinical Relevance—Based on the outcome of this case, osteochondral autografting appears to be a safe, valuable and realistic option for treating SCL of the proximal MTR of the talus in equine athletes.