On top of the shoulder blade (scapula) sits a bony mass called the acromion. This composes the top of the shoulder and serves as the headquarters for the deltoid muscle – connecting to the collarbone (clavicle) to form the acromioclavicular joint or AC Joint. The AC joint is an important part of the shoulder as it connects the shoulder to the rest of the body.

This joint frequently incurs damage as a result of an impact to the outside of the shoulder – as often seen in contact sports as well as in biking and skiing accidents. When this happens it is called an AC joint separation.

As a result, patients may notice a visible bump on the top of the shoulder. While not extremely painful, this happens when the end of the collarbone becomes detached from the acromion and the arm correspondingly sags – making the bump more pronounced. The initial injury may cause pain in the AC joint area and may be accompanied by some bruising and swelling.

When a severe displacement occurs, patients experience a tremendous amount of weakness in the deltoid muscle – indicating more serious ligament damage.

An AC joint separation, or shoulder separation, is often confused with a shoulder dislocation. The primary differences lie in the bones affected. In a shoulder separation, the area where the clavicle and scapula connect is disrupted, but in a shoulder dislocation the humerus is displaced from the socket, which is formed by the scapula.

Those at Risk
Those involved in extreme biking, motocross racing and other action sports are frequently diagnosed with AC joint separation.

Diagnosis
The prominent bump at the top of the shoulder is a good indictor of AC joint separation. Patient history and detail of how the injury occurred followed by an assessment of pain and tenderness at the joint will also help in the diagnosis. An X-ray may be performed in order to confirm that there is no bone fracture.

Treatment
Most AC joint separation problems can be addressed conservatively and will include a period of rest, cold compression and anti-inflammatory medication in order to relieve pain and reduce swelling. Range of motion exercises begin shortly thereafter in order to rebuild shoulder strength and flexibility.

In the case of severe displacement and corresponding weakness of the deltoid muscle, an outpatient surgical repair may be performed in order to restore the ligaments, which maintain the AC region. Rest, cold compression and range of motion exercises follow the procedure.

Shoulder impingement syndrome generally happens gradually – caused by the compression of the tendons of the rotator cuff, between part of the shoulder blade and the head of the humerus. The result is pain, weakness and loss of motion, as well as the potential for other conditions such as bursitis, and rotator cuff tendonitis and tears.

The compression, or impingement, may be prompted by a number of factors – acromioclavicular (AC) joint arthritis, calcification, structural abnormalities of the acromion, and overstressed and weakened rotator cuff muscles.

Those suffering from an impingement are usually prompted to seek medical consultation once night pain begins preventing comfortable sleep. Progressively symptoms become more prominent and range of motion greatly reduced.

Those at Risk
Shoulder impingement can affect the young athlete involved in overhead sports and older adult with a history of shoulder pain and stress alike.

Impingement syndrome can be generally classified into stages. Stage I is often associated with overuse injuries and includes edema and/or hemorrhage – most often occurring in patients under the age of 24. Stage II is more advanced and occurs most often in patients between the ages of 25 and 40. Fibrosis and more severe tendon changes are evident in Stage II. Stage III is found most often in patients over the age of 50 and involves a tendon rupture or tear – most likely the result of long-term vulnerability and corresponding degeneration.

Diagnosis
Patient history and pain analysis are first assessed when determining a diagnosis. A physical examination noting signs of impingement during passive shoulder motion are also important in determining if a patient suffers from shoulder impingement.

Depending on patient history, radiographic testing may be indicated in order to rule out other conditions and clearly identify tissue changes. And when a rotator cuff tear is suspected, magnetic resonance imaging by also be indicated.

Treatment
Conservative nonsurgical treatment is effective in addressing many impingement conditions, particularly in the early stages. These may include; cold compression to reduce swelling, nonsteroidal anti-inflammatory drugs (NSAIDs), a period of rest and refrain from activity that aggravates the condition, and a rehabilitative exercise program designed to strengthen shoulder muscles.

Injection therapy including lidocaine and corticosteroid may be recommended when impingement does not improve with initial conservative treatment. This is determined based on the age, condition and activity level of each patient.

When conservative treatment does not improve the condition, arthroscopic surgery may be indicated in order to facilitate decompression.

With the greatest range of motion than any other joint in the body, the shoulder is vulnerable to injury as well as many problems that can cause pain, tenderness and weakness. The shoulder is surrounded by four muscles (the infraspinatus, teres minor, supraspinatus, and subscapularis) and accompanying tendons, which are collectively called the Rotator Cuff and serve as part of a delicate balance of strength, flexibility and stability.

Rotator Cuff tears can result from a single action or the cumulative affect of gradual degenerative stress caused by long term involvement in overhead sports such as throwing, tennis and swimming – possibly following rotator cuff tendonitis, impingement, or dysfunction. Tears can also result from the degenerative affects of aging. Damage is classified as either extrinsic (initiated from the outside and resultant of a trauma or overuse), or intrinsic (initiated from the inside and resultant of degeneration with aging and calcific presence).

Symptoms generally include pain, weakness and loss of motion. Pain intensifies during overhead or above the shoulder activities. There may also be night pain that disrupts sleep.

Those at Risk
Athletes involved in overhead sports and the elderly experiencing tissue degeneration in the shoulder joint are most often diagnosed with a rotator cuff tear. Though, calcific tendonitis, which can eventually lead to a rotator cuff tear, may occur in those ranging in age from 30 to 50 years.

Diagnosis
Patient history and physical examination is key in establishing any diagnosis, but particularly for a rotator cuff tear. Pain is assessed as patients move through a series of passive shoulder movements involving forward flexion, as well as internal and external rotation at various rotations.

Radiographic testing is also helpful in eliminating the presence of calcific deposits and other contributing factors. In patients with a history of severe trauma or who experience extreme weakness, magnetic resonance imaging or an arthrogram may be indicated in order to determine appropriate treatment.

Treatment
Most rotator cuff injuries can be addressed nonsurgically and may respond to a course of conservative treatment that includes anti-inflammatory medication and rehabilitative exercises – involving all muscle groups instrumental in shoulder function, with both positive and negative force. If pain persists, cortisone injection treatment may be indicated.

And in more serious cases non responsive to conservative treatment, arthroscopic surgery may be indicated and instrumental in removing damaged portions of the bursa and repairing the torn rotator cuff tendons with suture anchors. Arthritis of the AC joint and other shoulder pathology can also be addressed at the same time.

A winged scapula is a shoulder injury or condition causing the scapula or shoulder blade to protrude out at the back, which is exaggerated when pushing against an object. It is the result of damage or a contusion to the long thoracic nerve of the shoulder or area muscle weakness. This nerve damage may also be the result of a direct trauma to the shoulder.

Aside from the protrusion of the scapula at the back, those suffering from winged scapula also experience pain, a reduction in shoulder movement, difficulty lifting and pressure on the scapula when sitting or leaning against a solid surface such as a chair.

Those at Risk
Athletes involved in contact sports placing the shoulder in jeopardy of a direct blow are often diagnosed with winged scapula.

Diagnosis
The protrusion at the back is a strong indicator of winged scapula. Patient history and physical examination are generally all that is necessary for diagnosis. Though, an X-ray may be indicated to thoroughly assess the area of impact and rule out other damage.

Treatment
Initial treatment for winged scapula is conservative and involves a complete rehabilitation program designed to strengthen the shoulder and surrounding muscles. If the condition is not improved with conservative treatment, surgery may be required to correct the problem and restore full shoulder function.