Radiographic imaging and possible causes of a carpal varus deformity in an Asian elephant (Elephas maximus)

The carpal region of an Asian elephant (Elephas maximus) with a clinically obvious varus deformity of the carpus was examined radiographically with a standard portable x-ray unit. Several dorsopalmar radiographs were taken at a short source-to-image distance, moving the beam center along the carpus. To obtain a single image of the carpal region, radiographs were assembled digitally using a composite technique. Radiographs revealed a deviation of the limb's axis of approximately 25 degrees in the region of distal physis of the radius and ulna and a wedge-shaped epiphysis of the ulna. Healed physitis due to trauma and subluxation of the middle carpal joint are discussed as possible causes of the deformity. The radiographic technique described proved to be helpful to evaluate a relatively large anatomic area in the carpal region of an adult Asian elephant with a varus deformity and may be an alternative tool to previously described single image radiography.