observed 12 different positions of movements and their relative correlation with injuries occurred during those movements. The evidence shows that putting the arm in a neutral position relieves tension on all ligaments and tendons. Stretching One article observed the influence of stretching techniques on preventive methods of shoulder injuries. Increased velocity of exercise increases injury, but beginning a fast-movement exercise with a slow stretch may cause muscle/tendon attachment to become more resistant to tearing. Muscle groups When exercising, exercising the shoulder as a whole and not one or two muscle groups is also found to be imperative. When the shoulder muscle is exercised in all directions, such as external rotation, flexion, and extension, or vertical abduction, it is less likely to develop a tear of the tendon. Treatment A rotator cuff tear can be treated operatively or non-operatively. No benefit is seen from early rather than delayed surgery, and many with partial tears and some with complete tears will respond to nonoperative management. Consequently, an individual may begin with nonsurgical management. However, early surgical treatment may be considered in significant (>1 cm – 1.5 cm) acute tears, or in young individuals with full-thickness tears who have a significant risk for the development of irreparable rotator cuff damage. Rotator-cuff surgery appears to result in similar benefits as nonoperative management. As a conservative approach has less complications and is less expensive it is recommended as initial treatment. Non-operative treatment Those with pain but reasonably maintained function are suitable for nonoperative management. This includes medications that provide pain relief such as anti-inflammatory agents, topical pain relievers such as cold packs, and if warranted, subacromial corticosteroid or local anesthetic injection. Topical glyceryl trinitrate appears effective at relieving acute symptoms however, headaches were reported as a side effect. A sling may be offered for short-term comfort, with the understanding that undesirable shoulder stiffness can develop with prolonged immobilization. Early physical therapy may afford pain relief with modalities (e.g. iontophoresis) and help to maintain motion. Ultrasound treatment is not efficacious. As pain decreases, strength deficiencies and biomechanical errors can be corrected. Shock wave therapy has seen widespread use since the 1990s to treat various musculoskeletal disorders including rotator cuff disease, but evidence of its efficacy remains dubious. In a review of 2020, the benefits and harms of shock wave therapy for rotator cuff disease, with or without calcificationcurrently, were investigated. They found low to moderate certainty