Pain with activity. Mild rotator cuff injuries are associated with inflammation without structural damage. Most of the symptoms occur during shoulder activities, such as reaching, lifting and throwing. As symptoms progress, the shoulder becomes painful at rest and even at night. Ice, activity modification and nsaid's are early treatments. Physical therapy and oral/injectable steroids are used in severe cases.
Pain, weakness, etc. Rotator cuff disorders (tears, strains, contusions, impingements, tendonopathies/tendonitis, etc) cause activity related shoulder pain. Pain is often worse when lifting or rotating the arm away from the body or with overhead activities including throwing. Pain can occur at rest, particularly at night. Other symptoms include weakness, loss of motion, noise/crepitus. Throwers lose velocity+location.