Chronic Shoulder Dislocation
Chronic Shoulder Instability
The shoulder is the most mobile joint in your body. It helps you lift your arm, rotate it, and reach above your head. It is capable of turning in several directions. This greater range of movement, however, can cause instability. Shoulder instability occurs when the head of the upper arm bone is forced out of the socket. This can happen as a result of a sudden injury or overuse. Once a shoulder is dislocated, it is vulnerable to repeated episodes. When the shoulder is loose and slips repeatedly, it is called chronic shoulder instability.
Shoulder Anatomy
Your shoulder is made up of three bones: your upper arm bone (humerus), your shoulder blade (scapula), and your collarbone (clavicle). The head or ball of your upper arm bone fits into a shallow socket in your shoulder blade. This socket is called the glenoid. Strong connective tissue, called the shoulder capsule, is the ligament system of the shoulder and keeps the head of the upper arm bone centered in the glenoid socket. This tissue covers the shoulder joint and attaches the top end of the arm bone to the shoulder blade. Your shoulder also relies on strong tendons and muscles to keep your shoulder stable.
Description
Shoulder dislocations can be partial, with the ball of the upper arm coming just partially out of the socket. This is called a subluxation. A complete dislocation means the ball comes all the way out of the socket. Once the ligaments, tendons, and muscles around the shoulder become loose or torn, dislocations can occur repeatedly. Chronic shoulder instability is the persistent inability of these tissues to keep the arm centered in the shoulder socket.
Possible Causes of Shoulder Instability
There are three common ways a shoulder can become unstable:
Shoulder Dislocation
A 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 first severe dislocation can lead to continued dislocations, giving way, or a feeling of instability.
Repetitive Strain
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 motions 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.
Multidirectional Instability
In a small minority of patients, the shoulder can become unstable without a history of injury or repetitive strain. In these patients, the shoulder may feel loose or dislocate in multiple directions, meaning the ball may dislocate out the front, back, or bottom of the shoulder. This is called multidirectional instability. These patients have naturally loose ligaments throughout the body and may be "double-jointed".
Non-Surgical Treatment for Shoulder Dislocation
Your doctor will develop a treatment plan to relieve your symptoms. It often takes several months of non-surgical treatment before knowing how well it is working. Non-surgical treatment typically includes:
Activity Modification: You must make lifestyle changes and avoid activities that aggravate your symptoms.
Non-Steroidal Anti-Inflammatory Medication: Drugs like aspirin and ibuprofen reduce pain and swelling.
Physical Therapy: Strengthening shoulder muscles and working on shoulder control can increase stability. Your therapist will design a home exercise program for your shoulder.
Surgical Treatment for Shoulder Dislocation
Surgery is often necessary to repair torn or stretched ligaments so they are better able to hold the shoulder joint in place.
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 minimally invasive surgery. Your surgeon will look inside the shoulder with a tiny camera and perform the surgery with special thin instruments.
Open Surgery: Some patients may need open surgery. This involves making a larger incision over the shoulder and performing the repair under direct visualization.
Post-Operative Care
After surgery, your shoulder may be temporarily immobilized with a sling. When the sling is removed, ligament rehabilitation exercises will be started. This will improve the range of motion of 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.