Shoulder tendonitis refers to inflammation of the tendons in the rotator cuff, a group of muscles and tendons that stabilize the shoulder joint. This condition is typically caused by excessive stress or repetitive strain on the tendon.
Acute tendonitis may result from a sudden or forceful movement, such as lifting an unusually heavy object, falling onto an outstretched hand, or forcefully pushing, pulling, or throwing. However, in most cases, shoulder tendonitis develops gradually due to repetitive overhead activities or motions that lead to microtrauma and cumulative inflammation over time.