Chronic Shoulder Instability
Shoulder instability occurs when the head of the upper arm bone is forced out of the shoulder socket. This can happen as a result of a sudden injury or from overuse.
Once a shoulder has dislocated, it is vulnerable to repeat episodes. When the shoulder is loose and slips out of place repeatedly, it is called chronic shoulder instability.
Common symptoms of chronic shoulder instability include:
- Pain caused by shoulder injury
- Repeated shoulder dislocations
- Repeated instances of the shoulder giving out
- A persistent sensation of the shoulder feeling loose, slipping in and out of the joint, or just “hanging there”
Three Common Ways the Shoulder Becomes Unstable
Severe injury, or trauma, is often the cause of an initial shoulder dislocation. When the head of the humerus dislocates, the socket bone (glenoid) and the ligaments in the front of the shoulder are often injured. The labrum — the cartilage rim around the edge of the glenoid — may also tear. This is commonly called a Bankart lesion. A severe first dislocation can lead to continued dislocations, giving out, or a feeling of instability.
Some people with shoulder instability have never had a dislocation. Most of these patients have looser ligaments in their shoulders. This increased looseness is sometimes just their normal anatomy. Sometimes, it is the result of repetitive overhead motion.
Swimming, tennis, and volleyball are among the sports requiring repetitive overhead motion that can stretch out the shoulder ligaments. Many jobs also require repetitive overhead work.
Looser ligaments can make it hard to maintain shoulder stability. Repetitive or stressful activities can challenge a weakened shoulder. This can result in a painful, unstable shoulder.
In a small minority of patients, the shoulder can become unstable without a history of injury or repetitive strain. In such patients, the shoulder may feel loose or dislocated in multiple directions, meaning the ball may dislocate out the front, out the back, or out the bottom of the shoulder. This is called multi-directional instability. These patients have naturally loose ligaments throughout the body and may be “double-jointed.”
Surgery is often necessary to repair torn or stretched ligaments so that they are better able to hold the shoulder joint in place.
Bankart lesions can be surgically repaired. Sutures and anchors are used to reattach the ligament to the bone.
Arthroscopy. Soft tissues in the shoulder can be repaired using tiny instruments and small incisions. This is a same-day or outpatient procedure. Arthroscopy is a minimally invasive surgery. Your surgeon will look inside the shoulder with a tiny camera and perform the surgery with special pencil-thin instruments.
Open Surgery. Some patients may need an open surgical procedure. This involves making a larger incision over the shoulder and performing the repair under direct visualization.
Rehabilitation. After surgery, your shoulder may be immobilized temporarily with a sling.
When the sling is removed, exercises to rehabilitate the ligaments will be started. These will improve the range of motion in your shoulder and prevent scarring as the ligaments heal. Exercises to strengthen your shoulder will gradually be added to your rehabilitation plan.
Be sure to follow your doctor’s treatment plan. Although it is a slow process, your commitment to physical therapy is the most important factor in returning to all the activities you enjoy.