Many patients who suffer from shoulder pain are often easily labeled as “frozen shoulder”. In fact, rotator cuff injuries are the most common type of shoulder disorder, while true frozen shoulder is relatively rare. Many patients with rotator cuff injuries can present with frozen shoulder, which is one of the reasons for misdiagnosis. The treatment of rotator cuff injuries can be very different from that of frozen shoulder. Therefore, it is important to understand the knowledge related to shoulder joint diseases and to take the correct treatment and rehabilitation methods. Rotator cuff injury (1) The rotator cuff is the collective name of four muscles: supraspinatus, infraspinatus, subscapularis and teres minor, whose main function is to govern the shoulder joint for movement in all directions. Rotator cuff injury is a tear of the rotator cuff tendon. It is common in middle-aged and elderly people and is mainly a chronic injury. In young people, the tendon may also be ruptured after trauma following prolonged strenuous exercise and repeated use of the shoulder joint (for example, playing badminton). (2) The main manifestations: two aspects, namely shoulder joint pain as well as weakness of the shoulder joint force. Nocturnal pain occurs, and many patients will wake up in pain due to shoulder pain while sleeping. The patient may also feel weakness in the affected limb, but can lift the affected side with a good hand. However, after the development of frozen shoulder, the range of motion of the shoulder joint is significantly limited. (4) Diagnosis: When the above symptoms appear, you should go to the hospital for examination. The presence of rotator cuff injury can be basically determined by questioning and physical examination of the patient. To confirm the diagnosis, an MRI is also required. (5) Treatment: The need for surgical treatment after a rotator cuff tear requires a comprehensive assessment. After the tear, it is impossible for the torn tendon to heal on its own due to retraction, so conservative treatments such as medication, closure, massage and massage, physical therapy, etc. are not effective for rotator cuff injuries and can only improve the pain symptoms in the short term, or are even ineffective. Violent massage and massage may lead to further expansion of the tear. Most of the torn rotator cuffs have to be surgically sewn back to the bone, and minimally invasive arthroscopic treatment is now routinely performed. Frozen shoulder (1) Frozen shoulder is an adhesive capsulitis, which is a self-limiting disease. It is a self-limiting disease, also known as frozen shoulder, and is caused by soft tissue lesions around the shoulder joint, resulting in joint pain and motor dysfunction. It is more common in patients around 50 years old and diabetic patients. (2) Main manifestations: Shoulder pain and movement disorders gradually increase, and after several months or even longer (usually about 1 year), the pain gradually decreases and function slowly recovers, and finally heals on its own. (3) Treatment: Take anti-inflammatory and pain-relieving drugs, physiotherapy, local closure, ice packs, etc. Appropriate massage helps to reduce the pain and improve the range of motion. Active functional exercise within the tolerable range. Be careful not to practice violently, as it may lead to rotator cuff tears.