Tendons are the fibrous structures that join muscles to bones. When these tendons become swollen or inflamed, it is called tendinitis. In many cases, tendinosis (tendon degeneration) is also present.
Calcific tendinitis; Bicipital tendinitis
Tendinitis can occur as a result of injury or overuse. Playing sports is a common cause. Tendinitis also can occur with aging as the tendon loses elasticity. Body-wide (systemic) diseases, such as rheumatoid arthritis or diabetes, can also lead to tendinitis.
Tendinitis can occur in any tendon. Commonly affected sites include the: