Your tendons do the job of attaching your muscles to your bones. Without them, movement would be impossible. When you injure a tendon, it becomes inflamed and painful. Any movement involving the tendon becomes difficult or painful. Tendinitis is the most common form of tendon injury. It’s not surprising that tendinitis tends to occur around the hardest-working tendons in the body–those at the ankles, knees, wrists, elbows and shoulders. Ice and rest can help your tendons to heal from injury. Infrared therapy may also help to treat tendinitis.