Shoulder

Pain in the shoulder is often caused by subacromial impingement: “pinching” of the rotator cuff and biceps tendon by the “roof” (acromion process) of the shoulder. Initial treatment is usually conservative, with physical therapy, oral anti-inflammatories, and occasional cortisone injections, If conservative treatment fails, arthroscopic surgery is usually successful in removing the “bone spur” that causes the impingement.

One of the most common impact injuries to the shoulder is an acromio-clavicular (AC) sprain, or separation. The collarbone and “roof” bone of the scapula (acromion process) collide, often damaging the surrounding ligaments.  Usually the injury can be treated conservatively with a period of protected activity. If the deformity of the joint is severe enough, or if the two bones over-ride each other painfully during activites, operative stabilization of the joint may be required.

A common cause of shoulder pain in weight lifters and patients with rotator cuff tears is arthritis of the acromio-clavicular (AC) joint. This is the small joint that connects the collarbone and the “roof” process of the scapula that protects the shoulder (acromion). Arthritis at this joint is common and usually does not cause symptoms, but occasionally the joint can become irritated and persistently painful. Initial treatment with rest, oral anti-inflammatories, topical anti-inflammatories and cortisone injections can be effective. If symptoms do not improve with conservative management, removal of the end of the collarbone either with a small open incision or with minimally invasive arthroscopic surgery usually results in good pain relief and return of function.

Tears of the rotator cuff of the shoulder are one of the most common causes of shoulder pain and weakness. The shoulder ball joint articulates with a small saucer like “socket” making the joint very mobile but potentially unstable. The rotator cuff is a 270 degree cuff of muscle and tendon that surrounds the ball of the shoulder, providing stable and powerful rotation against the saucer. There are four different muscles that give power to the tendons. The most commonly torn tendon is the supraspinatus, but larger tears can incorporate all four tendons. Rotator cuff tears become more prevalent in the general population with age, so the decision to treat a rotator cuff tear with conservative measures or surgery depends on the patient age, activity level, and ability to comply with restrictions and perform physical therapy for an extended time after surgery to optimize healing and improve range of motion and strength after operative repair. Often the tendon tear from the bone can be fixed arthroscopically.

Motion of the shoulder joint depends on slick surfaces of the ball and saucer joint that glide on each other without friction. As with the other major joints of the body (knee and hip), the surfaces of the shoulder joint can become worn, losing their smooth cartilage surface. As the arthritic process progresses, the ball and saucer bones themselves wear and become misshapen, often with large bone spurs and loose bodies filling the joint. The capsule becomes stiff and immobile, further restricting motion. The “bone on bone” contact makes any motion of the joint very painful and stiff. Conservative treatment consists of rest, decreased use of the shoulder, oral anti-inflammatories, and cortisone injections no more often than every four months or so. Definitive treatment, shoulder replacement, is usually very successful in alleviating pain and improving range of motion to perform everyday and athletic tasks.

The biceps muscle has a tendon that passes into the shoulder joint and attaches to the top of the socket. The tendon passes through a tunnel in the front of the shoulder and into the joint in a sheath that is made up of fibers from the top (supraspinatus) and front (subscapularis) rotator cuff tendons. This tendon can become inflamed or unstable because of impingement or a rotator cuff tear. The tendon can also become weak and frayed and sometimes will rupture spontaneously, causing immediate pain and sometimes a “popeye bulge” in the arm. Usually, shoulder pain after a biceps rupture resolves quickly without any treatment. Sometimes the biceps tendon needs to be released or repaired as part of a rotator cuff repair, as leaving it in a torn or unstable state can result in persistent pain even after a successful rotator cuff surgery.

One of the most common fractures in the shoulder occurs over the middle of the clavicle, or collarbone. Common causes for clavicle fracture include skiing, snowboarding, and bicycling accidents. If the fracture is relatively non-displaced (fragments are well aligned together) conservative treatment with a sling can result in good healing of the clavicle. However, if the bone ends are displaced, or significantly apart from each other, recent research suggests that surgical fixation of the fracture may give the best result. The fracture can be fixed with a plate and screws or a pin inside the bone.

Sporting injuries can result in shoulder dislocations and instability. The ball of the shoulder rotates off of the socket, often becoming stuck in the front, back, or bottom of the shoulder joint. Usually this injury is accompanied by a tear of the labrum and stretch of the capsule of the shoulder. The labrum is a fibrous cartilage rim around the socket that keeps the ball more stable in the socket, and the capsule is a complex collagen sheet that surrounds the ball and socket joint, keeping it stable. Often the labrum tear can heal and capsular tissue can “tighten up” with conservative treatment, but sometimes surgery is required to repair these structures and stabilize the shoulder. On occasion, significant bone loss can occur from the edge of the socket, making the likelihood of a recurrence of instability high even with an adequate soft tissue repair. In these cases bony augmentation of the socket and sometimes the ball is often necessary to obtain the best result.