Your upper arm bone (humerus) rests in a shallow socket to form the main part of your shoulder joint. The capsule and ligaments are the structures that hold the bones of the shoulder together. If these structures don’t hold the bones together as tightly as they should, the shoulder joint may feel too loose. This looseness allows the humerus to partially slide out of its socket, a condition called shoulder subluxation. The humerus may even come all the way out of its socket; this is called a shoulder dislocation. With multidirectional shoulder instability, the shoulder is loose in a way that allows the humerus to have extra movement in several directions.
What Causes Shoulder Instability?
Some individuals have naturally loose ligaments which can predispose them to instability. Shoulder instability can also occur in people who regularly perform shoulder motions that stretch out the joint capsule; gymnasts, pitchers, volleyball players, and swimmers are at higher risk for shoulder instability. Sometimes a sudden injury will cause increased symptoms. With multidirectional instability, the shoulder is loose with motions in several directions. This is different from patients who have instability following a shoulder dislocation that occurs as a result of a traumatic injury; these individuals generally have looseness in only one direction.
What Are the Symptoms of Shoulder Instability?
The main sign is a pain in your shoulder. The pain can start suddenly or slowly. Certain motions or positions (for example: winding up to throw a ball) may aggravate the pain. You may notice that your shoulder feels loose or that your arm feels weak.
How Is Shoulder Instability Diagnosed?
Your doctor will look at your shoulder and perform maneuvers to test for instability. He or she may take x-rays and/or send you for an MRI to examine the structure of the shoulder and rule out other conditions.
How Is Shoulder Instability Treated?
Rest — Avoid painful activities that stress the shoulder joint.
Ice — Especially after exercise. This helps control pain.
Medication — Ibuprofen (ex. Motrin® or Advil®) or Naprosyn (ex. Aleve®) may be taken to manage the pain.
Rehabilitation — Therapy may be needed to help strengthen the muscles that control and stabilize the shoulder joint. A physical therapist or athletic trainer will help develop an exercise program for each individual. Individuals should also be taught how to modify activities to prevent re-injury. It is important to continue rehabilitation exercises at home to prevent further injury.
Surgery — Most patients have significant improvement in their symptoms with physical therapy. Surgery is considered if other treatments fail. Many different procedures may be used to correct shoulder instability. The goal is to fix the cause. The doctor may use an arthroscope (a small surgical camera placed into small incisions) or make a larger incision for your surgery. After surgery, physical therapy is required to regain strength and range-of-motion.
Returning to Activities & Sports After Shoulder Instability
The goal is to return to sports as quickly and safely as possible. If you return to sports or activities too soon, or play with pain, the injury may worsen. Everyone recovers from injury at a different rate. Your doctor will work with you to determine when you can resume athletic activities. Regaining full range-of-motion and strength is vitally important, as well as improving the overall stability of the joint.
How Can Shoulder Instability Be Prevented?
Here are some guidelines to help protect the shoulder from injury:
Do regular exercise to strengthen the supporting muscles.
Use proper athletic training methods.
Do not increase exercise duration of intensity more than 10 percent per week.
Modify activities to prevent excessive external rotation and overhead motions of the shoulder. Do not play through pain. Pain is a sign of injury, stress or overuse.
Rest is required to allow time for the injured area to heal. If pain does not resolve after a couple of days of rest, consult your physician. The sooner an injury is identified, the sooner proper treatment can begin. The result is shorter healing time and faster return to sport.