The rotator cuff is a group of muscles and tendons that attach to the bones of the shoulder joint, allowing the shoulder to move and keeping it stable.

• Rotator cuff tendinitis refers to irritation of these tendons and inflammation of the bursa (a normally smooth layer) lining these tendons.
• A rotator cuff tear occurs when one of the tendons is torn from overuse or injury.

Causes

The shoulder joint is a ball and socket type joint. The top part of the arm bone (humerus) forms a joint with the shoulder blade (scapula). The rotator cuff holds the head of the humerus into the scapula. It also controls movement of the shoulder joint.

TENDINITIS

The tendons of the rotator cuff pass underneath a bony area on their way to attaching the top part of the arm bone. When these tendons become inflamed, they can become frayed over this area during shoulder movements. Sometimes, a bone spur narrows the space even more.

Rotator cuff tendinitis is also called impingement syndrome. Causes of this condition include:

• Keeping the arm in the same position for long periods, such as doing computer work or hairstyling
• Sleeping on the same arm each night
• Playing sports requiring the arm to be moved overhead repeatedly such as in tennis, baseball (particularly pitching), swimming, and lifting weights overhead
• Working with the arm overhead for many hours or days, such as in painting and carpentry
• Poor posture over many years
• Aging

TEARS

Rotator cuff tears may occur in two ways:

• A sudden, acute tear may happen when you fall on your arm while it is stretched out. Or it can occur after a sudden, jerking motion when you try to lift something heavy.
• A chronic tear of the rotator cuff tendon occurs slowly over time. It is more likely when you have chronic tendinitis or impingement syndrome. At some point, the tendon wears down and tears.

There are two types of rotator cuff tears:

• A partial tear occurs when a tear does not completely sever the attachments to the bone.
• A complete, full thickness tear means that the tear goes all the way through the tendon. It may be as small as a pinpoint, or the tear may involve the entire muscle tendon. With complete tears, the tendon has come off (detached) from where it was attached to the bone. This kind of tear does not heal on its own.

Symptoms

TENDINITIS

Early on, pain is mild and occurs with overhead activities and lifting your arm to the side. Activities include brushing your hair, reaching for objects on shelves, or playing an overhead sport.

Pain is more likely in the front of the shoulder and maytravel to the side of the arm.The pain always stops before the elbow. If the paingoes downthe arm to the elbow and hand, this may indicate a pinched nerve.

There may also be pain with lowering the shoulder from a raised position.

Over time, pain may be present at rest or at night,such aswhen lying on the affected shoulder. You may have weakness and loss of motion when raising the arm above your head. Your shoulder can feel stiff with lifting or movement. It may become more difficult to place the arm behind your back.

ROTATOR CUFF TEARS

The pain with a sudden tear after a fall or injury is usually intense. Right after the injury, you likely have weakness of the shoulder and arm. You may also feel a snapping sensation when trying to move the arm.

With a chronic tear, you often do not notice when it began. This is becausesymptoms of pain, weakness, and stiffness or loss of motion worsen slowly over time.

Most people with rotator cuff tendon tears have pain at night. Pain that is worse at night may wake the person. During the day, the pain is more tolerable, and usually only hurts with certain movements.

Over time, the symptoms become much worse, and are not relieved by medicines, rest, or exercise.

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