Surgical management and outcome of a type-III Salter-Harris fracture of the frontal plane of the distal radial physis in a foal.

CASE HISTORY: A 4-week-old Thoroughbred filly presented with lameness of acute, severe onset of the left foreleg (LF) of 3 days' duration.

CLINICAL FINDINGS: Diffuse swelling was present around the distal radius and carpus of the LF. Carpal varus that could be reduced manually was present. Radiographs revealed an intra- articular frontal-plane fracture in the distal radial epiphysis, which continued cranially through the distal radial physis (DRP). The lateral aspect of the DRP was wider than expected. Latero-medial carpal instability was resolved by placement of a lag screw from the dorsal midline through the epiphysis across the fracture. The DRP closed prematurely, resulting in a non-reducible carpal varus deformity, which was partially corrected surgically, and reduced the length of the limb.

DIAGNOSIS: Frontal-plane Salter-Harris type-III DRP fracture and varus deformity due to physeal injury.

CLINICAL RELEVANCE: Frontal-plane Salter-Harris type- III fractures do not appear to have been previously reported in horses and may be associated with a poor prognosis for athletic activity.