Standing repair of short frontal plane fractures involving the dorsoproximal articular surface of the proximal phalanx in six Thoroughbred racehorses.

Objective: To describe a technique and report outcomes for internal fixation of short frontal-plane fractures involving the dorsoproximal articular surface of the proximal phalanx (P1) in standing horses.

Study design: Short case series.

Animals: Six Thoroughbred racehorses with short, frontal plane fractures involving the dorsoproximal P1.

Methods: All fractures were located in the hindlimb. Horses presented with moderate lameness and marked effusion of the affected metatarsophalangeal joint. Fractures had a medial bias extending from the central aspect of proximal P1 to involve the dorsomedial prominence. Fractures were repaired under standing sedation, local anesthesia and radiographic guidance using a single 3.5 mm self-tapping cortical screw placed in lag fashion.

Results: Surgery was postponed by 24 h for one patient due to excessive movement during surgical preparation. The mean proximo-distal length of the radiographically apparent fracture plane was 23 mm (range: 19-28 mm). Mean time for screw placement was 13 min (range: 9-21 min). In five horses, postoperative radiographs were acquired and indicated resolution of the fracture plane. All horses raced postoperatively. The mean time from surgery to first race was 205 days (range: 144-284 days) and mean number of starts was 21 (range: 9-37). No complications were reported relating to the repair method.

Conclusion: Standing internal fixation of short, incomplete frontal plane fractures of the proximal phalanx, using a 3.5 mm self-tapping cortical screw, is a feasible method of repair. The technique should be viewed as an advanced standing fracture repair.