It is common to see this phenomenon in daily outpatient clinics. Patients present to the doctor with shoulder pain and significantly reduced range of motion, especially difficulty lifting the arm, and the doctor will often tell you that you may have frozen shoulder. The doctor will often tell you that you may have frozen shoulder, as if the incidence of frozen shoulder is the highest of all shoulder disorders. But in fact, this is due to the fact that there is still a large misunderstanding of shoulder disorders. According to the American Sports Medicine Association, frozen shoulder is actually an adhesive capsulitis, which is a self-limiting disease. The incidence of true frozen shoulder is relatively low, and rotator cuff injuries are the most prevalent shoulder disorders, followed by acromioclavicular impingement and shoulder disorders. It is evident that sometimes in life, even orthopedic surgeons who are not trained in shoulder disorders may have the same misconceptions as laymen. Some patients may therefore delay treatment, which may even lead to functional disability of the shoulder joint and seriously affect daily life. How to get out of the misunderstanding of frozen shoulder? The first step is to understand the shoulder joint from an anatomical point of view. The shoulder joint is a very complex joint. The humeral head and scapular glenoid form the glenohumeral joint. The humeral head is large while the scapular fossa is shallow, and the surrounding joint capsule is relatively weak, so the shoulder joint is the most mobile and flexible joint in the body. Some tendons end at the greater tuberosity of the humerus and wrap around the humeral head from the front, top and back of the shoulder joint to strengthen the stability of the shoulder joint; this tendon structure is called the rotator cuff tissue. An articular bursa covers the rotator cuff to reduce impingement friction between the rotator cuff and the rostral shoulder arch above it. Because of the high mobility of the shoulder joint, there exists an anatomical basis for susceptibility to shoulder joint disease. Second, we need to properly understand shoulder disorders. Statistically, the highest incidence of shoulder disorders is rotator cuff injury, which accounts for 30-40% of shoulder disorders. Rotator cuff injury is a very common degenerative disease of the shoulder joint, and its occurrence is positively correlated with age. The symptoms of rotator cuff tear are similar to those of subacromial impingement syndrome, but they are also accompanied by shoulder abduction weakness. Athletes, those who lift heavy objects, and those who suffer from traumatic injuries are prone to rotator cuff injuries. Typical symptoms are pain in the neck and shoulder at night and pain in the arm when lifting; sometimes they are afraid to sleep on the affected side and even wake up with pain; the shoulder joint may be weak when abducting, lifting or posterior extension, and sometimes there are difficulties even in personal hygiene, which seriously affects the patient’s life. The acromion impingement sign is a condition in which the acromion and subacromial bursa tissues collide with the rotator cuff tissues during shoulder abduction and supination, causing shoulder joint pain and supination dysfunction. In general, impingement and rotator cuff lesions occur more frequently in older individuals and throwing athletes. Since repeated throwing movements may affect the rotator cuff attachment point, which is congenitally low in blood supply, it is susceptible to rupture. The patient’s shoulder pain gradually worsens, with symptoms increasing when throwing or lifting the arm. The pain often radiates to the proximal lateral and middle parts of the arm. If treatment is delayed, the patient may experience severe muscle atrophy and sleepless nights; if left to develop, the later stages may lead to rupture of important tendons in the shoulder joint, seriously affecting the patient’s function and life. The third most prevalent shoulder joint disorder is shoulder instability. Due to trauma or degeneration of the joint structure, as well as the high mobility and relatively poor stability of the shoulder joint itself, the shoulder joint is prone to dislocation or subluxation. The affected shoulder will produce pain, impaired movement, limited function, and in some cases, habitual shoulder dislocation. If left untreated, bone defects and joint surface destruction can occur, making later treatment difficult and in some cases, even tricky. The combined incidence of the first three diseases accounts for almost 70% or more of shoulder joint diseases. In addition to these, many other shoulder joint diseases exist, such as acromioclavicular arthritis, biceps tendonitis and calcific supraspinatus tendonitis. This makes periarthritis diseases account for a much smaller percentage of shoulder diseases. Frozen shoulder, in essence, is adhesive capsulitis. It is a condition in which the soft tissues of the shoulder muscles, tendons, ligaments and joint capsule become congested and edematous. If your arm is painful when you extend it forward, extend it backward, lift it upward, abduct it and rotate it inside and outside, and if you are unable to comb your hair and wash your face, take a bath and rub your back, or grab the handrail when riding in a car because of pain, you may have frozen shoulder. Frozen shoulder mostly develops unilaterally, with the left side being more common than the right side, and a few patients can develop it bilaterally at the same time. The age of onset of frozen shoulder is consistent with the age of severe degeneration of the shoulder joint, and there is a history of injury to the shoulder or a history of local external fixation, cold, or hemiplegia. The main symptoms are shoulder joint pain, muscle weakness, and impaired movement. The most obvious symptom is pain. The degree and nature of pain varies widely, from a dull pain to a cutting pain. It is also called “Leaky shoulder wind” in Chinese medicine. The term “wind” refers to an evil disease. “Wind is the longest of all diseases. Wind has the characteristics of holding cold, damp, heat and other pathologies to invade the body; clinically, wind-cold is the most common. In the case of old and weak, the wind-cold evil is easy to take advantage of the weakness. When cold invades the meridians, the blood vessels become stagnant and “pain is caused when they do not pass”, so pain is the main cause of shoulder pain. When cold invades the tendons and joints, joint movement is restricted and flexion and extension are unfavorable. According to the occurrence and development of frozen shoulder, it can be roughly divided into 3 phases, namely, acute phase, chronic phase, and recovery phase. There are no clear boundaries between the stages, and the duration of each stage varies greatly from person to person. Recent medical research has found that periarthritis is not a completely isolated disease, but may be a special manifestation of certain underlying diseases, such as diabetes, cervical spondylosis, coronary heart disease, lung cancer, etc. Therefore, it is important to be alert. According to foreign studies on diabetic patients, periarthritis is indeed associated with high diabetes, and many diabetic patients suffer from periarthritis. Other studies have also found that a high percentage of patients with periarthritis have diabetes. The relationship between periarthritis and cervical spondylosis is even closer. In cervical spondylosis, the hyperplastic bone compresses the sympathetic fibers in the anterior cervical nerve roots. This chronic irritation alters the blood supply to the shoulder joint and its surrounding tissues, leading to atrophic changes in the shoulder joint. Also, the irritation of the compressed cervical nerve roots can cause shoulder entrapment pain and reduce its movement. Among lung cancer patients, there are sometimes shoulder pain as the first symptom, but this shoulder pain has its own characteristics: although the pain is severe, it is usually not accompanied by obvious upper limb movement disorder; no pressure point can be found in the shoulder. The purpose of rehabilitation treatment for frozen shoulder is to improve blood circulation in the shoulder, strengthen metabolism, reduce muscle spasm, stretching adhesions and contractures of tissues, in order to reduce and eliminate pain and restore normal function of the shoulder joint. In the acute stage or early stage, it is best to take some fixation and analgesic measures to relieve the patient’s pain, such as suspension with a triangular scarf and treatment of the shoulder with heat, physiotherapy or closure. 2. The chronic stage is mainly characterized by shoulder joint dysfunction. At this time, functional exercise and massage are the main treatment, together with physical therapy. The main method of rehabilitation for frozen shoulder is medical gymnastics. (1) Finger wall climbing exercise: Stand sideways or in front, lift the affected forearm, stick your index and middle fingers against the wall, and then slowly make a wall climbing movement upward along the wall. (2) Raise the affected arm and repeatedly touch the back of the head; the sick side hand behind the body and lift up to touch the back. If the affected arm has difficulty moving, use the healthy hand to help lift the affected hand. Frozen shoulder usually has a long course, especially if the shoulder joint function is limited, the time can be extended to several months or even a year. Therefore, elderly people with frozen shoulder should insist on daily rehabilitation exercises and gradually increase the time and number of exercises in order to achieve better results. Exercise should be done to cause mild pain, but should avoid causing severe pain. In addition, acupuncture and physiotherapy can also have certain effects. Frozen shoulder can be prevented. Older people generally lack activity and have poor blood circulation in the upper limbs and tissues around the shoulder. Therefore, the joint capsule and tendons of the shoulder joint are prone to degeneration, calcification and inflammation. If elderly people usually pay attention to exercise and exercise their upper limbs and shoulders, they can effectively avoid the occurrence of frozen shoulder.