The biceps muscle, in the front of the upper arm, helps stabilize the upper arm bone (humerus) in the shoulder socket. It also helps accelerate and decelerate the arm during overhead movement in activities like tennis or pitching. Strong, cord-like structures called tendons connect one end of the biceps muscle to the shoulder in two places. At the other end of the muscle, tendons connect the biceps muscle to the smaller bone (radius) in the lower arm. If the tendons become inflamed or irritated, the condition is called tendinitis.

Causes
Injuries to the biceps tendons are commonly caused by repetitive overhead activity. Overuse, aging and stress can also cause the tendon to deteriorate, even if there is no inflammation present.

Symptoms
Symptoms include pain when the arm is overhead or bent; localized tenderness as the tendon passes over the groove in the upper arm bone; and occasionally, a snapping sound or sensation in the shoulder area.

Treatment
Initial treatment is conservative. The first step is to rest the arm and shoulder. Ice applications and nonsteroidal anti-inflammatory medications such as ibuprofen can help reduce inflammation. Your physician can also recommend stretching and progressive strengthening exercises to build muscle endurance and restore range of motion so that you can gradually return to overhead activity.

If the pain results from shoulder instability or from pressure on the tendon from the shoulder bones, your orthopaedist may recommend arthroscopic surgery.