There are many causes of shoulder pain, and shoulder injuries are more common in young people, athletes and the elderly population. Two very common injuries in the narrow bony gap of the shoulder called the subacromial space are localized irritation and inflammation called rotator cuff impingement syndrome, and tendon injury called rotator cuff tear. These two conditions can exist independently or together. Rotator cuff tears are most likely caused by rotator cuff impingement and aging changes in the rotator cuff tendons. Persistent irritation and inflammation of the subacromial bursa and rotator cuff tendons can lead to degeneration and tearing of the rotator cuff tendons. Of these, the supraspinatus tendon is the most commonly involved rotator cuff. The supraspinatus tendon forms the top of the rotator cuff and is located in a narrow gap under the acromion. The main cause of rotator cuff tears is traumatic injury or degeneration from the aging process. Patients can exhibit symptoms, but many are asymptomatic. Total rotator cuff tears are uncommon in young, athletic individuals; when they do occur, they are usually due to a high-energy injury to the rotator cuff that is associated with throwing or over-the-top-over-the-top sports. In older adults, rotator cuff tears are more likely to be the result of prolonged wear and tear. Several scientific studies have demonstrated that two-thirds of 70-year-olds have rotator cuff tears, and many are asymptomatic.