Torn Rotator Cuff Diagram

Unlike the knee, which has strong ligamentous support (a ligament is a soft tissue structure connecting bone to bone), the main shoulder joint (glenohumeral "ball and socket") relies heavily on the rotator cuff for support. Check the rotator cuff illustration for an excellent view of this.

Since the shoulder can achieve a large range of motion the rotator cuff is unfortunately susceptible to tears, tendonitis, impingement, bursitis and strains. Glenohumeral dislocations and acromioclavicular separations occur because of a large amount of stress on the shoulder. These injuries can occur from falling with an outstreched arm while playing sports such as soccer, hockey or basketball or by falling down a flight of stairs.

Although trauma to the shoulder is common in sports or falls, people can have shoulder pain without ever knowingly injuring their shoulder.

Many of these problems occur in today's society because of poor posture. A person with rolled shoulders and a forward head carriage will likely have upper back, neck, shoulder and arm pain. Also, this posture is very stressful on the supraspinatus muscle and tendon.

Tears of this muscle and its tendon happen quite easily from simple activities such as pull starting a lawn mower, opening a heavy door or even by lifting an insignificant amount of weight.