The shoulder is a unique and complex joint. Bones, ligaments, tendons and muscles all work together to provide the greatest range of motion of any joint in the body. Because the joint is so complex, there are a number of conditions that may result in shoulder instability.

Shoulder instability can be caused by an injury, such as a direct impact from a fall or sports such as football and hockey; overuse of a muscle, tendon or ligament; arthritis or degenerative joint disease, and other conditions, including:

  • Rotator Cuff Tears: It’s possible to have a rotator cuff tear and not realize it. There are acute tears (from an injury) and degenerative tears (from wear and tear over time), and each situation may require a different treatment approach.
  • Labral Tears: The upper arm bone socket is surrounded by a rubbery cartilage called the labrum, which cushions the socket, adds stability, decreases friction, and connects tendons to the shoulder joint.
  • Shoulder Dislocation: A dislocated shoulder is a painful injury that occurs when the head of the upper arm bone (humerus) pops out of the shoulder joint. It is often caused in contact sports or from a fall.
  • Shoulder Sublaxation: Shoulder sublaxation is a partial dislocation of the shoulder joint. It occurs when the upper arm bone (humerus) slips partially out of the socket (glenoid) due to weakness in the rotator cuff or a blow to the shoulder area.

One of Lancaster Orthopedic Group’s shoulder specialists will diagnose shoulder instability primarily through a medical history and physical exam. He or she will ask about your pain, about past shoulder injuries, and about how your symptoms are affecting your regular activities. You may also need an X-ray or arthroscopy to give the physician a better look at the muscles and ligaments of the shoulder.

Once the cause of the shoulder instability has been determined, there are a variety of treatment options, from conservative treatment to surgery.