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Tendinitis is a condition caused by the tearing of tendon fibers and subsequent inflammation in the tendon. Tendons are the strong connective tissue that connect muscle to bone.
When a muscle contracts, it pulls on the tendon, which is composed of tissue that cannot stretch. The tendon then transmits that pulling force to the bone and moves the bone, producing movement. Tendinitis usually results from excessive repeated demands placed on the tendon by the muscle. Tendinitis is not usually caused by a sudden injury; it is more commonly a result of a long period of overuse. Tendinitis occurs frequently with active individuals and those whose occupational tasks require repetitive motion.
Tendons that commonly become inflamed include:
Repeated overuse of the tendon will cause small tears to develop in the tendon fibers. As a result, the body will initiate the injury repair process in the area and lay down scar tissue. Inflammation will develop in the area as part of the injury repair process. Inflammation increases the blood supply, bringing nutrients to the damaged tissues along with infection-fighting agents. The result is swelling, tenderness, pain, and heat. Redness may occur if the injury is close to the skin. Since many cases of tendinitis result from chronic inflammatory conditions that develop from long periods of overuse, the inflammatory process is not as exaggerated as with an acute injury. Therefore swelling, heat, and redness are not always visible in a tendinitis complaint because the inflammation is really at a low level.
Recent research has found that tendinitis sometimes develops as a side effect of treatment with quinolones, which are a group of antibiotics frequently used to treat bacterial infections. The tendon most likely to be affected by these drugs is the Achilles tendon, and the tendinitis usually develops within the first few weeks of antibiotic treatment.
Author Info: Whitney Lowe, Rebecca J. Frey PhD, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Alternative Medicine, 2005
This feature is for informational purposes only and should not be used to replace the care and information received from your healthcare provider. Please consult a healthcare professional with any health concerns you may have.
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