Compensatory humeral overgrowth in a dog

A severe angular limb deformity secondary to premature closure of the dista l ulnar growth plate was diagnosed in a two year old Shetland sheep dog. Ra diographic and computerized analysis demonstrated elongation of the ipsi-la teral humerus. The elongation was interpreted as a form of compensatory bon e overgrowth similar to that described in the tibia in response to prematur e closure of femoral growth plates. The regulators of bone growth and possi ble mechanisms of compensatory overgrowth are reviewed.