Use of an external ring fixator for correction of an acquired angular limb deformity in a donkey

Numerous techniques for surgical correction of angular limb deformities in horses involving an osteotomy of the affected bone and stabilization with an internal fixation device have been described. However, because the osteotomy typically has to be performed at the level of the physis, leaving little bone between the physis and the nearest joint, stabilizing the osteotomy by use of internal fixation devices may be difficult. In horses with severe chronic angular limb deformities, the amount of soft-tissue contracture may make it impossible to correct the deformity during a single procedure without causing stretch injuries to the adjacent tendons and neurovascular structures. Adjustable external ring fixators incorporating hinged rods on 1 side of the limb and an angular motor assembly on the other may be useful for treatment of severe chronic angular limb deformities in younger equids, because they allow for gradual correction of the deformity.