Your elbow joint is made up of 3 bones, cartilage, ligaments and fluid. Muscles and tendons help the elbow joint move. Any of these structures can become injured, turn into pain and limit your function. A common cause of pain and limitation is tendonopathy (formerly known as tendonitis) an inflammation or degeneration to the tendons that attach the muscles to bone. Tendonopathy of the elbow often comes as a result of overuse in sports like golf or tennis, or something more innocent like repeated clicking on mouse or typing.