A 10 wk old male shih tzu (1.9 kg) was presented for severe non-weight-bearing lameness of the right thoracic limb. Radiographs revealed luxation of the right humeroulnar joint (type II), with severe external rotation of the proximal ulna.
The ulna was manually reduced to achieve articulation with the medial part of the humeral condyle under general anesthesia, which was maintained by two positive-profile threaded pins placed into the lateral part of the humeral condyle in a caudal to cranial direction ("stopper" antiluxation pins).
The lameness improved at 5 days postoperatively. One pin appeared loose radiographically and both pins were removed at 30 days postoperatively. The dog showed no lameness with mildly limited range of motion with radiographic findings including the mild residual humeroulnar incongruity and degenerative joint disease at the final follow-up (6.8 yr postoperatively). We propose that this extra-articular method to prevent luxation is advantageous for its minimal adverse effect on elbow range of motion, as compared with the previously described methods including transarticular pinning and external fixators.
This case report describes a novel treatment option for congenital humeroulnar luxation in very young dogs that maintains reduction and allows early return to function.
