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.

The biceps muscle in the upper arm splits near the shoulder in a long head and a short head - both of which attach to the shoulder in different places. At the opposite end of this muscle is the distal biceps tendon, which connects to the smaller lower arm bone, the radius.

While all of these connections work to help the muscle stabilize the shoulder, allow for rotation of the lower arm, and adjust for accelerated and decelerated overhead movements, the long head of the biceps tendon is particularly vulnerable to injury because it travels through the shoulder joint to its attachment point.

If the long head of the biceps tendon is torn, arm strength is severely decreased and patients are unable to turn their arm from palm down to palm up. A bulge in the upper arm may also be evident, and, depending on the location of the tear, difficulty lifting overhead or bending the elbow may also be experienced.

Patients experiencing a rupture may hear a "snap" in the shoulder during an overhead movement, followed by shoulder aching and possibly upper arm bruising.

Those at Risk
A rupture may occur as part of a rotator cuff lesion in young athletes involved in rigorous overhead sports. In patients over the age of 50, a rupture near the scapular origin of the long head of the biceps tendon is often seen after only minimal trauma - often the result of degeneration and history of shoulder stress.

Diagnosis
A thorough patient history and physical examination will most likely confirm suspicions. A special X-ray (arthrogram), or magnetic resonance imaging (MRI) may be indicated for patients with a history of shoulder pain in order to verify the condition of the rotator cuff muscles.

Treatment
Conservative nonsurgical treatment is effective in addressing these types of conditions. 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.

When conservative treatment does not resolve the problem, or if the rupture was part of a rotator cuff lesion in a young athlete or involves a complete tear of the distal biceps tendon, surgery may be indicated in order to reattach the tendon to the bone. Rehabilitative and strengthening exercises begin shortly thereafter.

Rotator cuff disease is the vulnerable environment created within the shoulder joint by a history of shoulder overuse or repetitive stress conditions - including rotator cuff tendonitis, subacromial bursitis, impingement syndrome, and general dysfunction involving partial or complete tearing of the rotator cuff tendons.

It is a disorder of the musculotendinous cuff surrounding the glenohumeral joint and is a continuum of pathology involving a range of rotator cuff conditions leading to degenerative shoulder stability. Symptoms usually include a dull ache at the upper outer arm and shoulder during activity, with overhead activities becoming increasingly difficult. Pain in the shoulder may extend down to the elbow, and neck pain on the same side may also develop later as scapular elevators are excessively used to compensate for abnormal glenohumeral motion.

In early stages, patients may also experience snapping within the shoulder and night pain and discomfort. Later, weakness and loss of shoulder motion become increasingly evident.

Those at Risk
Rotator cuff disease in large part is a condition related to age and the affects of lifelong wear and tear. It most frequently affects athletes involved in forceful overhead or throwing sports, as well as laborers frequently using hammers and jackhammers.

The type of related conditions experienced depends on the age of the patient and stage of the disease. While any single condition related to rotator cuff disease or a single tear resulting from a trauma can occur at any age, there is a general pattern in determining the various stages of rotator cuff disease. Patients in their 40s are most often affected by inflammatory conditions such as bursitis and rotator cuff tendonitis. Patients in their 50s may be diagnosed more frequently with tendinosis, or degeneration. And patients in their 60s often experience tears in response to the weakened environment and joint degeneration.

Diagnosis
A thorough patient history and physical examination will most likely confirm suspicions. A special X-ray (arthrogram), or magnetic resonance imaging (MRI) may be indicated for patients with a history of shoulder pain in order to verify the condition of the rotator cuff muscles and shoulder joint.

Treatment
Conservative nonsurgical treatment is effective in addressing many of the symptoms associated with rotator cuff disease. 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 and improve range of motion.

Injection therapy including lidocaine and corticosteroid may be recommended when pain persists despite initial conservative treatment, or if lesions are present but surgery is not advised for a particular patient. This is determined based on the age, condition and activity level of each patient.

When conservative treatment does not improve the condition after a six-month period, arthroscopic surgery may be indicated in order to facilitate decompression. Debridement may be indicated for frayed or partially torn tendons.

For more serious tears, exploratory arthroscopy and surgery may be indicated in order to reattach the tendon to the bone. Rehabilitative strengthening and range of motion exercises begin shortly thereafter.

Acromioclavicular (AC) joint arthritis, also known as AC joint arthrosis and osteoarthritis of the AC joint, is the wearing down of the cartilage in the AC joint. It is most often diagnosed in those in their 40s and older.

Unlike glenohumeral arthritis, or shoulder arthritis, which is the wearing down of the cartilage of the humerus (long arm bone) at the socket of the shoulder joint, AC joint arthritis is the wearing down of the cartilage at the acromion and the clavicle at the AC joint.

The primary cause for AC joint arthritis is general use. Though lifelong activities placing unusual stress on the shoulder joint, or earlier AC joint injuries such as shoulder separation, puts some at greater risk than others for the disease. Others more susceptible to the disease include workers who must use their arms for extended periods of time or athletes involved in overhead lifting. Blunt force to the shoulder, in either contact sports or in an accident, also leave a person susceptible.

Symptoms of AC joint arthritis include: pain and sensitivity at the front of the shoulder around the joint; discomfort when applying pressure to the area while sleeping; pain during certain arm and shoulder movements that may span the shoulder area, chest and neck; and swelling. Patients may also experience a reduction in range of shoulder motion.

Diagnosis
After assessing a patient's history and a physical examination, an X-ray will help show the degree of joint damage. And a series of X-rays can help determine the rate of progression.

Treatment
Treatment is determined based on the affect the arthritis has had on a patient's joint at the time of diagnosis, as well as the type of joint affected. It may involve conservative treatment - including cold compression, anti-inflammatory medications such as aspirin or ibuprofen, refrain from inflammatory activity, cortisone injections, and rehabilitation and occupational therapy to improve range of motion.

In more advanced cases nonresponsive to conservative treatment, either a resection arthropolasty or a complete shoulder replacement may be indicated.

The earlier the diagnosis, the greater the chance of preventing irreversible damage.