What are rotator cuff disorders?
The rotator cuff is a group of tough, flexible fibers (tendons) and muscles in the
shoulder . Rotator cuff disorders occur when tissues in
the shoulder get irritated or damaged. Rotator cuff disorders include:
- Inflammation of
the tendons (tendinitis) or of a bursa (bursitis). In
the shoulder, a bursa is a small, fluid-filled sac that serves as a cushion
between the tendons and the bones.
- Impingement, in which a tendon
is squeezed and rubs against bone.
- Calcium buildup in the tendons,
which causes a painful condition called calcific tendinitis.
Partial or complete tears of the rotator cuff tendons. See a picture of a
torn rotator cuff tendon .
How does the shoulder work, and what does the rotator cuff do?
The shoulder is a joint with three
main bones: the upper arm bone (humerus), the collarbone (clavicle), and the
shoulder blade (scapula). The bones are held together by muscles, tendons, and
ligaments. The rotator cuff keeps the upper arm bone
in the shoulder socket and lets you raise and twist your arm.
shoulder is a ball-and-socket
joint. The ball at the top of the upper arm bone fits
into the socket of the shoulder blade. This socket is shallow, which lets you
move your arm in a wide range of motion. But it also means that the muscles and
tendons of the rotator cuff have to work hard to hold the bones in place. As a
result, they are easy to injure and are prone to wear and tear.
What causes rotator cuff disorders?
Most rotator cuff disorders are caused by a combination of:
- Normal wear and tear. Using your shoulder for
many years slowly damages the rotator cuff. As you age, everyday activities can
lead to changes in the rotator cuff, such as thinning and fraying of the
tendons and reduced blood supply.
- Overuse. Activities in which you
use your arms above your head a lot-such as tennis, swimming, or house
painting-can lead to rotator cuff problems. Even normal motions made often over
a long period can stress or injure the rotator cuff.
Both normal wear and tear and overuse can lead to
impingement, when a tendon rubs against bone. This damages and irritates the
tendon, which causes bleeding and inflammation. Over time, damage to the tendon may build up, so the tendon is more easily
It takes great force to tear a healthy rotator cuff
tendon. This can happen during sports, an accident, or a severe fall. But even
a simple movement like lifting a suitcase can cause a rotator cuff tear in an
older adult or someone whose shoulder is already damaged.
What are the symptoms?
Symptoms of a rotator cuff
disorder include pain and weakness in the shoulder. Most often, the pain is on
the side and front of the upper arm and shoulder. It may hurt or be impossible
to do everyday things, such as comb your hair, tuck in your shirt, or reach for
something. You may have pain during the night and trouble sleeping.