”Frozen shoulder” is a very familiar name. Many people have a history of shoulder pain and are often labeled as “frozen shoulder”, as if “frozen shoulder” is the most prevalent and well-known chronic disease of the shoulder joint. It seems that “frozen shoulder” is the disease with the highest incidence and is a well-known chronic disease. In fact, a large proportion of these cases are rotator cuff injuries, which are very different from frozen shoulder in terms of treatment. It is easy to confuse the two, and even some orthopedic surgeons who do not specialize in the shoulder joint often refer to it as “frozen shoulder”. It is a self-limiting disease that usually resolves on its own after 1 to 2 years. The exception is the “diabetic frozen shoulder”, which causes more pain and is poorly treated non-surgically. The clinical symptoms of frozen shoulder are widespread pain in the shoulder joint (the patient cannot point out the exact location of the pain), reduced range of motion (no pain in the remaining range of motion), frequent nighttime pain, and in severe cases, difficulty combing hair, putting on makeup, and dressing for meals. ”The rotator cuff is composed of four muscles surrounding the shoulder joint, which protect the shoulder joint, maintain the stability of the shoulder joint, and are responsible for the movement of the shoulder joint. Rotator cuff injuries are associated with both trauma and degeneration. The clinical symptoms vary depending on the muscles involved. The clinical symptoms of rotator cuff injury are mainly pain in the anterolateral aspect of the shoulder joint, which may radiate to the deltoid muscle. If left to develop, the corresponding muscle atrophy, joint stiffness and osteoporosis will appear in the later stages, which will seriously affect the function of the shoulder joint. In terms of treatment, through exercise, including “pendulum exercise”, “wall climbing”, “hanging bar”, physical therapy, and oral anti-inflammatory and pain-relieving drugs, 90% of patients with frozen shoulder will be able to recover in 1 to 2 years. -90% of patients will get relief in 2 years. If you have a rotator cuff injury, the above exercises will aggravate the already existing injury. MRI can clarify the extent of the injury, and depending on the extent of the injury, treatment such as closure, muscle strength exercises, and avoidance of repetitive pain-inducing movements can be used. The current shoulder arthroscopy technology is quite mature in repairing the rotator cuff, and the surgery has been coveted by the majority of patients for its significant effect, small trauma, short hospital stay, and early return to activity.