Tendinitis is the inflammation or irritation of a tendon, which are the thick, fibrous cords that connect muscle and bone. Tendinitis most often occurs around the shoulders, elbows, wrists, knees, and heels, but can occur at any of the tendons.

The most common symptom is pain and tenderness just outside a joint. Tendinitis problems come in various names for each joint, such as Tennis elbow, Golfer’s elbow, Pitcher’s shoulder, Swimmer’s shoulder, and Jumper’s knee.

Most cases of tendinitis are successfully treated with rest, physical therapy, and medication, which reduce pain. Surgery can be needed when the condition is so severe that the tendon ruptures.