Tendinitis is inflammation of a tendon. Tenosynovitis is tendinitis accompanied by inflammation of the protective covering around the tendon (tendon sheath).
Tendons are fibrous cords of tough tissue that connect muscles to bones. Some tendons are surrounded by tendon sheaths.
Tendinitis usually occurs during middle or older age, as the tendons weaken and become more susceptible to injury and inflammation. (Weakening of the tendon, called tendinopathy, usually results from many small tears that occur over time. Affected tendons may gradually or suddenly tear completely.) Tendinitis also occurs in younger people who exercise vigorously (who may develop rotator cuff tendinitis—see Muscle, Bursa, and Tendon Disorders: Rotator Cuff Tendinitis and see Sports Injuries: Rotator Cuff Injury) and in people who do repetitive tasks.
Certain tendons are particularly susceptible to inflammation.
Certain joint diseases, such as rheumatoid arthritis, systemic sclerosis, gout, diabetes, and reactive arthritis (previously called Reiter syndrome), can cause tenosynovitis. In people with gonorrhea, especially women, gonococcal bacteria can cause tenosynovitis, usually affecting the tissues of the shoulders, wrists, fingers, hips, ankles, or feet.
The inflamed tendons are usually painful when moved or when pressed. Moving the joints near the tendon, even a little, may cause pain, depending on how severe the tendinitis is. Occasionally, the tendons or their sheaths swell and feel warm.
If tendinitis lasts a long time, calcium may become deposited. The area around the shoulder joint is often affected. In addition to being painful, the shoulder may feel stiff and weak. It may snap or catch when moved.
Doctors can usually diagnose tendinitis based on the symptoms and results of a physical examination. Sometimes magnetic resonance imaging (MRI) or ultrasonography is helpful.
Rest, immobilization with a splint or cast, and application of heat or cold—whichever works—are often helpful. Taking nonsteroidal anti-inflammatory drugs (NSAIDs) for 7 to 10 days can reduce the pain and inflammation.
Sometimes corticosteroids (such as betamethasone, methylprednisolone, or triamcinolone) and anesthetics (such as lidocaine) are injected into the tendon sheath. Rarely, the injection causes pain hours later because the corticosteroid temporarily forms crystals inside the joint or sheath. This pain lasts less than 24 hours and can be treated with cold compresses and pain relievers.
Other drugs may be used, depending on the cause. For example, if gout is the cause, indomethacin or colchicine may be used.
After inflammation is controlled, exercises to increase the range of motion should be done several times a day.
Chronic, persistent tendinitis, as can occur in rheumatoid arthritis, may have to be treated surgically to remove inflamed tissues, and physical therapy may be needed after surgery. Surgery is occasionally needed to remove calcium deposits from areas of long-standing tendinitis, such as the area around the shoulder joint.
De Quervain Syndrome
De Quervain syndrome (washerwoman's sprain) is swelling and inflammation of the tendons or tendon sheaths that move the thumb outward.
De Quervain syndrome usually occurs after repetitive use, particularly wringing, of the wrist. It often develops in new mothers, probably because they repeatedly pick up their baby by stretching out their arms and using only their wrists. It can also develop with rheumatoid arthritis.
The main symptom is aching pain on the thumb side of the wrist and at the base of the thumb, which becomes worse with movement. The area at the base of the thumb near the wrist is also tender.
Doctors diagnose this disorder when they detect tenderness over the two tendons on the thumb side of the wrist, usually accompanied by swelling. To detect tenderness, doctors ask people to bend their thumb into their palm and wrap their fingers over the thumb. Then people are asked to bend their wrist away from the thumb. People are likely to have De Quervain syndrome if this movement causes pain at the same side of the wrist as the thumb.
New mothers may be able to avoid this disorder if they use their entire arm and hold their wrists straight when they lift their baby.
Movements that cause pain should be avoided. Rest, warm soaks, and nonsteroidal anti-inflammatory drugs (NSAIDs) may help people with mild symptoms. People with more severe symptoms usually feel better after treatment with a corticosteroid injection and a thumb splint. Sometimes one or two more injections, separated by several weeks, are needed. If these methods do not relieve symptoms, people may need surgery.
Rotator Cuff Tendinitis
Tendinitis may develop in the tendons of the muscles that help move, rotate, and hold the shoulder in place (rotator cuff).
Rotator cuff tendinitis (see Sports Injuries: Rotator Cuff Injury) is the most common cause of shoulder pain. It causes pain when the arm is raised (particularly between 40 and 120°) or when people dress. People often have pain during the night, especially when they lie on the affected arm.
Symptoms may occur suddenly and be severe, especially after physical activity, or they may develop more slowly and be milder.
Range-of-motion exercises, nonsteroidal anti-inflammatory drugs (NSAIDs), and sometimes a corticosteroid injection can be used for treatment.
Last full review/revision February 2013 by Joseph J. Biundo, MD