Two major problems associated with tendons include tendonitis and tenosynovitis. Tendonitis, inflammation of a tendon (the tough cords of tissue that connect muscles to bones) can affect any tendon, but is most commonly seen in the wrist and fingers. When the tendons become irritated, swelling, pain, and discomfort will occur.
Tenosynovitis is the inflammation of the lining of the tendon sheaths which enclose the tendons. The tendon sheath is usually the site which becomes inflamed, but both the sheath and the tendon can become inflamed simultaneously. The cause of tenosynovitis is often unknown, but usually strain, overuse, injury, or excessive exercise may be implicated. Tendonitis may also be related to disease (i.e., diabetes or rheumatoid arthritis).
Common tendon disorders include the following:
Lateral epicondylitis (tennis elbow) - A condition characterized by pain in the back side of the elbow and forearm, along the thumb side when the arm is alongside the body with the thumb turned away. The pain is caused by damage to the tendons that bend the wrist backward away from the palm.
Rotator cuff tendonitis - A shoulder disorder characterized by the inflammation of the shoulder capsule and related tendons.
DeQuervain's tenosynovitis - The most common type of tenosynovitis disorder characterized by the tendon sheath swelling in the tendons of the thumb.
Trigger finger/trigger thumb - A tenosynovitis condition in which the tendon sheath becomes inflamed and thickened, thus preventing the smooth extension or flexion of the finger/thumb. The finger/thumb may lock or trigger suddenly.