Rotator Cuff Tendonitis - What are the Rotator Cuff Muscles?

Rotator Cuff Tendonitis is basically inflammation of the rotator cuff muscles. The function of these muscles helps to stabilize the joint during movement. It consists of four important muscles of the shoulder:

Supraspinatus Muscle

This relatively small muscle comes from the shoulder blade (scapula) and then inserts on top of the shoulder joint (greater tubercle of the humerus). The function of this muscle helps it to abduct the shoulder or move your hands up and away from your side. It is responsible for most of the power during initial shoulder movement and then the other muscles take over.

Infraspinatus Muscle

The muscle is slighter bigger than the suspraspinatus and originates from the lower half of the shoulder blade (infraspinous fossa of the scapula) and then attaches to the capsule of the shoulder joint. This muscle helps to move the shoulder joint outwards.

Subscpularis Muscle

This muscle originates from the middle two thirds of the shoulder blade and then attaches to the front of the shoulder joint (lesser tubercle of humerus and anterior shoulder capsule). The function of this muscle helps the shoulder to rotate inwards and when you raise your arms, it helps the joint move downward and forward that prevents the joint from popping out.

Teres Minor Muscle

This muscle comes from the upper two thirds of the shoulder blade and attaches to the head of the shoulder joint (greater tubercle of the humerus). This muscle is important in helping the shoulder joint move outwards (laterally rotate the shoulder joint).

Causes

They are many possible causes of rotator cuff tendonitis. Most tendonitis could be due to old age which makes the tendon weak and fragile. Sometimes, most people will have no pain or symptoms but can be readily detected with an X-ray or ultrasound.

Another main cause could be due to sports related trauma or injuries. For example, these tendons can be torn while reaching for a basketball or slamming your shoulder on the ground in volleyball.

Symptoms of Rotator Cuff Tendinitis

The obvious symptoms are usually swelling, severe/moderate pain around the shoulder joint, lack of shoulder movement, weakness and ability to do normal daily tasks like putting your clothes on a clothes line.

Specific tests can be done with muscle strength testing, range of motion, X-rays and ultrasound.

Treatment

All treatment must be specific to the condition of the injury. Generally, the first option is always to choose the most conservative treatment like physical therapy, massage therapy, chiropractic, hot/cold therapy, ultrasound therapy and other such treatments. However, if it becomes too severe, then cortisone can be injected into the joint.

Surgery of the shoulder is the last resort and prognosis is poor.