Repetitive throwing places severe stress on the elbow joint. The throwing motion stretches the tendons and ligaments on the inner side of the elbow and compresses the structures on the outer side. These forces can damage tissue and bone, especially in young athletes whose bones have not fully matured.
Medial Epicondylitis, commonly called golfer’s elbow, results from overuse of the muscles and tendons of the forearm. This can gradually deteriorate the common flexor tendon, which attaches to the medial epicondyle (the bony bump on the inner side if the elbow. It can usually be treated without surgery.
Medial Ulnar Collateral Ligament (MUCL) Injury
Repetitive throwing can sprain or tear the medial ulnar collateral ligament, typically the anterior band located on the inner side of the elbow between the ulna and humerus. An MUCL injury causes pain on the inner side of the elbow. A complete tear may require a type of reconstructive surgery commonly called Tommy John surgery.
Medial Apophysitis, commonly called Little League elbow, usually occurs in children before they reach puberty. Childrens’ bones have growth plates on the ends – areas that allow the bones to expand. Repetitive throwing can damage the ligaments or fracture the growth plates, causing pain and swelling on the inner side of the elbow. In severe cases, surgery may be required.
In Osteochondritis Dissecans, repetitive throwing disrupts the blood supply to the cartilage that cushions the ends of the bones. This can cause sections of cartilage and bone to pull away or break loose completely. This condition commonly causes pain on the outer side of the elbow and may cause the joint to click or lock. Surgery may be required to remove any loose fragments.