Shoulder Instability
The shoulder is the most flexible joint in the body. And because of its ability to move in many directions, it can sometimes lead to an increased tendency for instability.
Causes
This often happens from an injury that causes a dislocation (when the head of the upper arm bone is forced out of the shoulder socket). After a shoulder dislocation, it can be more susceptible to repeated dislocations due to injury to the soft tissue and bony supports of the shoulder.
In some cases, instability may be present without an initial dislocation. Sometimes a genetic predisposition where tissue of the body can lead to ligaments that are too elastic and stretch too easily. All the joints of the body may be too loose and cause joints, such as the shoulder, to be more susceptible to being dislocated. This can be referred to as being double jointed.
Symptoms
When the shoulder dislocates it is accompanied with intense pain, swelling, and inability to move the arm. A dislocated shoulder may cause damage to the nerves around the shoulder joint which may cause areas of numbness in the arm or shoulder. It may also cause weakness in the muscles of the shoulder. This is usually temporary and often resolve over time when the nerves recover.
The shoulder may often slip (sublux) when the arm is put in certain positions, such reaching overhead. Subluxation of the shoulder usually causes a quick feeling of pain, like something is slipping or pinching in the shoulder.
Treatment
A shoulder dislocation is treated by relocation or placing it back into proper position. This procedure is typically performed by a physician.
The treatment of shoulder instability usually starts with physical therapy. The muscles and the ligaments around the shoulder joint are major components in creating stability of the joint. If the muscles and ligaments have been weakened by injury such as a dislocation, they can be strengthened to compensate to some extent. The most important muscles in the shoulder for stability are the rotator cuff muscles.
If physical therapy is unsuccessful in stabilize the shoulder, surgery may be suggested. Many types of shoulder operations are designed to stabilize the shoulder. Most of these surgeries are designed to tighten the ligaments that are loose.
Exercises for Shoulder Instability
External rotation:
Stand with your arm at your side and elbow bent to 90 degrees. Place a rolled up towel between your arm and the side your body as shown.
Squeeze your shoulder blade back and down toward your buttocks and hold that position.
While holding an elastic band, start with your forearm and wrist near your stomach. Next, roll your arm outward from your stomach area while maintaining your arm against the towel and with your shoulder blade held down and back the entire time. Return to starting position and repeat.
2. Internal rotation:
Stand with your arm at your side and elbow bent to 90 degrees. Place a rolled up towel between your arm and the side your body as shown.
Squeeze your shoulder blade back and down toward your buttocks and hold that position.
While holding an elastic band, start with your forearm and wrist near your stomach. Next, roll your arm outward from your stomach area while maintaining your arm against the towel and with your shoulder blade held down and back the entire time. Return to starting position and repeat.
Written by Daniel Le, DPT