Condylar fractures of the third metacarpal bone and third metatarsal bone in 75 horses: Radiographic features, treatments, and outcome

Abstract

SUMMARY The prevalence and location of condylar fractures of the third metacarpal bone and third metatarsal bone were analyzed for 69 Thoroughbred, 4 Standardbred, and 2 grade horses. The fractures were classified as complete-displaced (46), complete-non-displaced (6), and incomplete (21). Four horses had special incomplete (3) and complete (1) fractures of the third metatarsal bone, extending from the medial condyle into the diaphysis. Bone healing was monitored radiographically and the development of joint disease was analyzed on the basis of the type of fracture, presence of comminution of the fracture, and existence of lytic subchondral bony lesions. Postmortem examination of fractured condyles in 8 horses that were euthanatized at intervals ranging from a few days after injury up to 2 years following surgical repair permitted observations of the healing process. The ability to return to racing for Thoroughbreds with surgical repair, using bone screws, was compared with that for Thoroughbreds managed without surgery. Twelve of 38 horses with complete displaced fractures continued racing after surgery and 0 of 6 continued racing with conservative treatment. The 6 horses with complete-nondisplaced fractures were operated on and 4 continued to race following surgery. Eleven of 21 horses with incomplete fractures were operated on and 9 of the 11 returned to racing. The other 10 were treated conservatively and 9 of these continued to race. The winnings per race for the 35 Thoroughbreds analyzed were less than before the fracture occurred in those with complete fractures and in those with incomplete fractures treated with surgery. The 9 Thoroughbreds with incomplete condylar fractures treated conservatively had higher earnings after treatment than before.