DEFINITION AND NOMENCLATURE
The rotator cuff is a group of strong, rope-like 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 (Figure 1), 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.
WHAT IS THE FUNCTION OF A ROTATOR CUFF?
The shoulder is a joint with three main bones: the upper arm bone (humerus), the collarbone (clavicle), and the shoulder blade (scapula). Muscles, tendons, and ligaments hold the bones together. The rotator cuff keeps the upper arm bone in the shoulder socket and lets you raise and twist your arm.
The 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 motions. 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.
CAUSES FOR DISORDERS OF ROTATOR CUFF
Most rotator cuff disorders are caused by a combination of:
- Normal wear and tear: Using the shoulder for many years slowly damages the rotator cuff. As one ages, everyday activities can lead to changes in the rotator cuff, such as thinning and fraying of the tendons and reduced blood supply.
- Overuse: Activities that involve raising your arms overhead, such as tennis, swimming etc. can lead to rotator cuff problems. Even repetitive normal motions that are made over a long period of time 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, scar tissue replaces healthy tissue, and the tendons become stiff, stringy, and more easily injured.
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.
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 combing your hair, tucking your shirt in, or reaching for something. You may even experience pain during the night and may have trouble sleeping.
TESTS & DIAGNOSIS
To diagnose a rotator cuff disorder, doctors ask about any shoulder injuries or past shoulder pain. They also do a physical exam to see how well the shoulder works and to find painful areas or activities. Moving your arm in certain ways can help a doctor learn about the condition of the rotator cuff.
You may have an X-ray to check the bones of the shoulder. If the diagnosis is still unclear, the doctor may order an imaging test, such as an MRI or an ultrasound. (See figure 2)
Without treatment, the shoulder may get weaker and one may not be able to lift the arm.
For most rotator cuff disorders, doctors recommend these steps first:
- Rest the shoulder. Use the arm, but do so carefully. Don't keep the shoulder still with a sling or brace. This can cause the joint to become stiff (frozen shoulder).
- Use ice or heat on the shoulder, whichever feels better.
- Take anti-inflammatory drugs (NSAIDs) to relieve pain and reduce swelling and inflammation. Examples include aspirin, ibuprofen and naproxen.
- Avoid positions and activities that are uncomfortable, such as lifting or reaching overhead. Stop any activity that hurts the shoulder.
The doctor may also suggest physical therapy. Physical therapy can reduce pain and help your shoulder be stronger and more flexible. In physical therapy, you learn exercises to stretch and strengthen your shoulder. After you learn the exercises, you can do them at home.
It is important to give treatment time to work. It may take from a couple of weeks to several months to get good results.
If other treatments don't help, your doctor may give you injections of steroid medicine in the shoulder. The injections probably don't cure rotator cuff disorders, but they can help relieve pain and inflammation so you are able to do exercises to strengthen the shoulder. The shots may also help your doctor find out if your shoulder pain is from your rotator cuff. If a steroid shot near the rotator cuff relieves your pain, even if the pain comes back later, it means the rotator cuff—not some other shoulder problem—is causing the pain.
Most rotator cuff disorders do not require surgery, but doctors may perform surgery if a rotator cuff tendon is torn or if several months of other treatments have not helped.
- Surgery may be a good choice if you are young and your rotator cuff has been in good shape. Surgery may not work as well if your tendons are weak and frayed.
- Surgery is not a substitute for physical therapy. Even after surgery, you may need months of physical therapy to have a full recovery.
Surgical options include arthroscopic fixation or open fixation. In arthroscopy, small tiny incisions are made on the skin through which the arthroscope (an instrument attached to a camera) is placed in the joint and the pathology inspected. Through other incisions (‘portals’), instruments are inserted to remove the bone spur (in impingement) or repair the torn cuff tendons. The surgery itself lasts 1 to 2 hours and is an outpatient surgery; i.e. the patient goes home the same day without admission to the hospital. An open surgery is one in which a small incision is made over the skin and the surgery is done under direct visualization. The recovery period for the arthroscopic surgery is shorter and hence more and more surgeons are moving towards arthroscopic fixation. However, the success rates for both surgeries are equal.
RISKS: The risks include infection at the site and other medical complications during anaesthesia.
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