Shoulder instability describes a range of conditions affecting the main shoulder joint. This joint is held in place and supported by the rotator cuff, muscles, tendons, tissue, and cartilage. Failure in any or all of these structures can lead to a looseness that is diagnosed as shoulder instability. In normal individuals, the ball portion of the shoulder joint can move approximately one inch forward or backward. For patients with shoulder instability, a greater range of movement is reported.
Patients who seek medical care for shoulder instability often experience a partial or complete dislocation. These may occur due to looseness in the joint from repetitive activities or as the result of a traumatic event such as a football player being tackled or the occurrence of a motor vehicle accident.
Chronic shoulder instability causes several symptoms which include:
- Subluxation, where the shoulder slips, but does not dislocate or come completely out of the socket. You may feel a quick pain associated with the slipping.
- Frequent dislocation of the shoulder which can be quite painful. Movement will increase the pain.
- A numb spot could develop below the top of your shoulder due to stretched nerves. Slight, temporary muscle weakness could accompany.
Your doctor can diagnose shoulder instability by inquiring about your medical history and performing a physical examination. Additional information may be obtained through X-ray images and MRI.
Treatment for shoulder instability is based on a variety of factors including the severity of the condition, along with your age, activity level, occupation, and natural degree of looseness in the joint.
If you have experienced a painful, traumatic dislocation, you will find instantaneous relief after realignment. A trip to the emergency room for realignment may be necessary. In young patients, traumatic dislocations have a high recurrence rate, so early repair is considered if activity will be continued. Patients over the age of 40 have low recurrence rates and can usually be treated non-operatively. If a rotator cuff tear accompanies the dislocation, surgical repair may be necessary.
When surgery is necessary, your doctor will consider open surgery or arthroscopy. With either method, your surgeon realigns and reattaches the shoulder joint. Through this surgical repair, the joint is tightened and restored to normal tension as much as possible. The goal is to stabilize your shoulder while retaining range of motion.
Patients who are loose jointed (multi-directional instability) are treated with a regimen of rehabilitation exercises. The shoulder joint will have greater stability if the muscles and tendons that support the shoulder can be made to work more efficiently. If an exercise program fails, open surgery may be recommended.
After surgery, a sling is worn for four weeks to protect the shoulder and restrict mobility as the tissue heals. Gentle range of motion exercises are performed. After this initial period, you can begin a program of strengthening exercises. Most people can return to athletic activity that places stress on the shoulder after four months of rehabilitation.