A thorough examination is important to help rule out other causes of shoulder pain. Some of the symptoms a patient will present with are pain, which is often worse when the arm is raised overhead, instability, weakness and limited range of motion. Other complaints are swelling, numbness and propping of the shoulder. The pain could start acutely or worsening in a course of a known repetitive activity. In older people, the symptoms are often deceptive with no precise injury [6].

Imaging tests are the gold standard in rotator cuff tears. A plain radiograph of the shoulder is useful and the typical views are AP view to determine acromiohumeral distance which may be reduced. It will also show reactive changes at the rotator cuff insertion site like sclerosing and cyst formation. An outlet view will show the acromion shape and slope while the axillary view identifies the position of the humeral head in relation to the glenoid [7]. Magnetic resonance imaging is highly sensitive and specific and it shows the site, size and characteristics of rotator cuff injuries.

Ultrasonography is also useful and highly sensitive in detecting full thickness tears but it is extremely dependent on the skill of the observer. Electrodiagnostic testing can also be done to rule out nerve involvement and nerve conduction as a source of pain.

This could either be non-operative or operative. Non-operatative treatment is reserved for those who have relatively normal function in the affected limb. The modality includes the use of oral and topical analgesics to relieve pain, a shoulder sling to reduce movement of the joint, physical therapy to avoid joint stiffness due to immobility. As pain decreases, a strengthening program is instated to return the joint to its normal strength [8].

When operative treatment is indicated, the surgeries of choice are arthroscopy, mini-open and open repair. Arthroscopy was initially reserved for very small tears but with the advancement in technology, have been as successful as open surgery in the repair of large tears.

Most athletes respond well to nonsurgical treatment in primary outlet impingement without full thickness rotator cuff tears. When surgery is done, response is determined by a number of factors including age, size and pattern of the injury, degree of retraction, quality of the tissue and quality of the repair.

Rotator cuff tear could either be an acute episode or from a chronic degenerative insult. An acute episode results from a great force on the muscle such as a fall on the outstretched arm. A lesser force could also cause a tear if the muscle has already started undergoing some degeneration. It could also result from sudden heavy lifting.

Chronic causes include reduced perfusion, degeneration related to old age, repeated heavy lifting especially overhead and bone spurs, which are extra pieces of bone that may grow and irritate the muscle [2].

People at risk for this injury are older people, certain athletes like basket-ballers, and construction workers.

Rotator cuff injury occurs in as much as 40% of the population with the incidence increasing with age. Rotator cuff tears are commoner in males, affect the dominant arm more, and people that are involved in physical activity and those with a history of trauma [3].

The two main mechanisms of rotator cuff tears are injury and degeneration and they could either be due to intrinsic, when it occurs from within the rotator cuff itself, and extrinsic, when the source is from surrounding structures like the acromion, factors. A rotator cuff tear could also either be a partial thickness or a full thickness tear.

The amount of stress needed to acutely tear a rotator cuff depends on the condition before application of the force. In a healthy tendon, the force required is greater than that required in a tendon with preexisting degeneration [4].

Chronic tears are a result of wear that occurs over time, due to extended use, poor biomechanics or muscular imbalance and aging. They usually occur more in the dominant arm and the stressor is mainly from repeating the same shoulder motions frequently. Another factor in chronic tear is diminished blood supply. This occurs mainly in older people and it impairs the ability if the tendons to repair themselves leading to tears.

A third mechanism is what is referred to as impingement syndrome. The tendons of the rotator cuff pass through the subacromial space below the acromion, when they become inflamed, the space becomes smaller and there is pain on motion. Repeated impingement can lead to inflammation of the tendons and bursa and result in the syndrome [5].

Some preventive measures include, resting shoulder when experiencing pain, regular shoulder exercises, using proper form when lifting weight, and adequate rest periods in occupations that involve heavy lifting [9].

The shoulder joint has a wide range of motion, and it gives up stability for this wide range of motion making it a relatively unstable joint. Its stability is ensured by bony and muscular components. Part of this muscular component is the rotator cuff muscles. It is made up by 4 muscles; the supraspinatus, infraspinatus, subscapularis and teres minor [1]. These muscles come together via their tendons to stabilize the joint while it is in motion.

Definition

Rotator cuff tear is a tear in the muscles that help to stabilize the shoulder joint. These tears could be partial or full. They could also occur suddenly or build up over time.

Cause

It can result suddenly from trauma. It can also result from long term degeneration of the tendon associated with aging. Repeated motions of the joint in occupation that require lifting and reaching can also cause it as well as reduced blood supply to the tendon from any cause.

Symptoms

Symptoms include pain which could be worsened by raising the hand above the head. There could also be swelling and redness of the shoulder. The shoulder may also be numb and the range of motion may be lost. 

Diagnosis

Diagnosis is usually done by a plain X-ray of the joint. An MRI which is a more expensive procedure is also a very reliable diagnostic tool. An ultrasound in the hands of a skilled observer can also diagnose the condition.

Treatment

This involves the use of pain medications to reduce pain, shoulder slinging and physical therapy. For those who do not respond to conservative management or in whom rapid recovery is required, surgery may be performed [10]. 

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