Deltoid muscle abduction contracture.

A child with an abduction contracture of the left shoulder secondary to diffuse fibrosis of the deltoid muscle was successfully treated by recession of the inserting muscle fibers proximally. Previously reported cases of deltoid muscle contracture were secondary to fibrous cords or nodules within the muscle. This patient's contracture may be related to either a brachial plexus birth injury or may be similar to the idiopathic fibrosis seen in the quadriceps muscle.