Treatment of shoulder joint luxation with glenoid ostectomy in a miniature donkey.

Case Description: A 13-year-old 128-kg miniature donkey gelding was evaluated for right forelimb lameness of 7 weeks' duration.

Clinical Findings: Muscular atrophy of the infraspinatus and supraspinatus muscles over the right scapula with a palpable bony prominence over the point of the shoulder was evident. At the walk, the cranial phase of the stride was reduced with adduction of the distal aspect of the limb, dragging of the toe, and lameness (grade, 4/5). Lateral and craniocaudal radiographs of the right shoulder joint revealed lateral luxation of the humerus in relation to the scapula with bony proliferation and remodeling of the humeral head.

Treatment And Outcome: Glenoid ostectomy was performed. Immediately after surgery, the donkey was able to intermittently stand squarely on the limb but maintained a reduced cranial phase of the stride at the walk. The donkey had no short-term complications and was discharged from the hospital 11 days after surgery. Following discharge, the donkey was confined to a box stall for 60 days, followed by a gradual increase in movement to full pasture turnout. The lameness continued to improve, and at 15 months after surgery the donkey was turned out in pasture and had mild lameness (grade, 3/5) at the trot. Mild muscular atrophy of the supraspinatus and infraspinatus muscles was present with no signs of pain on palpation or manipulation of the limb. Shoulder joint radiography at 15 months after surgery revealed remodeling of the glenoid cavity of the scapula and humeral head with formation of a pseudoarthrosis.

Clinical Relevance: Glenoid ostectomy should be considered as an alternative to shoulder joint arthrodesis in small equids with shoulder joint luxation. Other indications for this procedure could include chronic osteoarthritis or fractures affecting the shoulder joint.