The Shoulder

The shoulder has the greatest range of motion of any joint in the body. It is our shoulders that allow us to put our hands where they need to be for work, play, and all of our daily activities. To manage this, the shoulder has to have the right balance of strength, flexibility, and stability. Loss of this balance can lead to pain and injury. Maintaining this balance through exercises aimed at stretching and strengthening can help avoid shoulder problems. 

Rotator Cuff Injuries

The shoulder joint is surrounded by four muscles and their tendons. These are collectively referred to as the rotator cuff. The rotator cuff is surrounded by an empty sac, or bursa, which helps the tendons slide. The rotator cuff is susceptible to many problems which can cause weakness, tenderness and pain. These problems include overuse tendinitis, which can be caused by certain activities.

Overhead sports such as throwing, swimming, or tennis, can lead to tendinitis. If the space between the rotator cuff and the bone above it is narrowed, the rotator cuff tendons and the overlying bursa can get squeezed. This will lead to bursitis and tendinitis. This is called impingement. Occasionally a calcium deposit may form in the rotator cuff and cause acute inflammation of the tendon and bursa. We call this calcific tendinitis. The rotator cuff tendons are also susceptible to the process of aging. As we get older, the rotator cuff tendons degenerate and weaken. A rotator cuff tear can occur due to this degeneration alone, or when the weakened tendons are stressed during activities or accidents. Most rotator cuff problems can be treated with rest, medication and gentle exercises, but pain which persists more than two weeks should be evaluated by a physician.

More on Rotator Cuff Disease

Shoulder Replacement

The shoulder joint can be affected by many forms of arthritis. Osteoarthritis, rheumatoid arthritis, and traumatic arthritis are the most common types affecting the shoulder. Shoulder replacement (or shoulder arthroplasty) can be performed in many patients who have pain which has not responded to other treatments. Though less common than hip or knee replacements, shoulder arthroplasty has been performed since the 1950's with good success. The results of replacement surgery depend greatly on the type of arthritis, the quality of the bone, and the condition of the muscles around the shoulder. The primary goal of replacement surgery is pain relief. Shoulder arthroplasty is generally effective in relieving pain. The secondary goal of replacement surgery is improvement in range of motion and function. The extent of improvement varies greatly depending on the severity of the preoperative condition, the preoperative range of motion, and the postoperative rehabilitation. A shoulder replacement consists of two major parts, a humeral component, which replaces the bone at the end of the upper arm, and a glenoid component, which replaces the shoulder blade socket. The humeral component is made of metal, and the glenoid component of plastic. In some circumstances, such as severe fractures, only the humeral component is used. This is referred to as a hemiarthroplasty.

Common Shoulder Injuries Among Athletes

The shoulder is at risk for injury in many sports. The rotator cuff (see above) can be injured through overuse or through trauma. Rotator cuff tendinitis is common in overhead sports such as baseball, tennis, volleyball, and swimming. Rotator cuff tears can occur if the tendons are overloaded in weight lifting or football. There are ligaments which hold the shoulder bone in its socket. The shoulder has a very large range of motion, and needs some flexibility of the ligaments to allow for that range. But if the ligaments become stretched or torn, this can lead to instability. A mild amount of instability will allow the shoulder to slip part way out of socket, called a subluxation. When the shoulder comes completely out of its socket this is called a dislocation. Subluxation or dislocation can occur with nearly all sport activities. The ligaments of the shoulder are attached to the socket at the labrum. Tearing of the labrum sometimes occurs with instability. Another part of the shoulder commonly injured is the acromioclavicular or AC joint. The clavicle or collarbone meets the shoulder at the acromion where a small joint is found. This joint can be injured to varying degrees in a fall onto the outside part of the shoulder. Injury to the AC joint is called an AC separation. AC separations occur in contact sports and are frequently seen in skiing and biking falls. Clavicle fractures are common injuries seen frequently in sports where speed or contact are involved.

Shoulder Exercises

These exercises are aimed at strengthening the rotator cuff. Increasing cuff strength can decrease symptoms and effects of instability, impingement and tendinitis, as well as prevent some injuries.
 

Rotator Cuff Repair Rehabilitation Protocol

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