BY - Fred B. McCashin, VMD, MSc -

Don't Give up too Soon - The term Sweeney Shoulder refers to a horse's shoulder musculature that has atrophied. The appearance of the shoulder blade once the muscles have shrunk is wide up near the withers and narrow near the point of the shoulder (at the actual joint) and the long spine of the scapula can be easily palpated the length of the shoulder blade. The shape of the scapula (shoulder blade) is obvious once the muscles have shrunk. The cause is usually trauma to the suprascapular nerve which supplies the major muscles on the scapula. Horses can collide with trees or be kicked by others while turned out. I once treated two horses who were "warming up" for a barrel racing event and they collided in the warm-up arena going opposite directions at speed. They both suffered temporary loss of function of the suprascapular nerves. I treated them with anti-inflammatories and physical therapy. They both recovered, but one took a long time. On the one that took longer, the muscles did waste away and it was accurate to describe him as a Sweeney shouldered horse before the nerve re-grew and the muscles returned to their normal size. There are some horses that are not able to regenerate an adequate nerve supply, either because the trauma was so severe that the nerve was cut or scarred, or the area lost blood supply so that healing was diminished. This can be the case if the neck of the scapula is fractured and it is not stabilized enough. The prognosis varies with the trauma. Full recovery is expected with minor trauma and prompt treatment. Of course, there are "shades of grey" in between. There have been Sweenied horses that took a year to respond, so don't give up on them too soon.