Every autumn and winter season, some middle-aged and elderly people are always complaining about shoulder pain, and office workers are also prone to this state due to long-term ambulatory work and long-term tension in the shoulder muscles and ligaments, which is actually a manifestation of frozen shoulder. What is frozen shoulder? The full name of frozen shoulder is bursitis around the shoulder joint, also known as “shoulder coagulation”, “fifty shoulder”, the age of onset is mostly around fifty years old. The symptoms of frozen shoulder are: stiffness and inflexibility of the joint, localized pain, and obvious pressure points, especially at night when the pain increases. When the doctor examines the shoulder joint, it makes a “creaking” sound, which is called “golden chicken and frog” in Chinese medicine, which is a characteristic of the disease. Frozen shoulder usually occurs on one side of the shoulder, and some patients have so much pain that they cannot sleep at night. In severe cases, it is difficult to carry bowls and eat, to put on clothes and sleeves, to untie the belt when urinating and defecating, and to wash the face and comb the hair. The pathological mechanism is that the inflammatory substances stick to the muscles, tendons and bursa around the shoulder, making the shoulder completely immobile over time. It is worth mentioning that there are two common types of frozen shoulder, namely impingement of the shoulder and subacromial bursitis. Acromion impingement: The acromion and subacromial bursa tissues impinges and squeezes against the rotator cuff tissue during shoulder abduction and supination, causing shoulder 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 inherently low in blood supply, it is prone 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 subacromial bursa, also known as the subdeltoid bursa, is one of the largest bursae in the body and is located beneath the acromion, rostroscapular ligament and deep facet fascia of the deltoid muscle. Painful movement restriction and limited pressure are the main symptoms of subacromial bursitis. The pain is progressively worse and is more prominent at night. The pain increases with movement, especially during abduction and external rotation (compression of the bursa). The pain is usually located deep in the shoulder, involving the stops of the deltoid muscle, and can also radiate to the scapula, neck and hands. Frozen shoulder can be divided into two types: primary and secondary: primary frozen shoulder: the pathogenesis of frozen shoulder is due to degenerative changes in the body, osteophytes around the joint, decreased synovial fluid secretion, increased friction between muscles, tendons, ligaments and joint capsule, resulting in aseptic inflammation, oedema under the tissue, and pain due to stimulation of peripheral nerves. Due to the pain, the patient’s shoulder joint activity decreases, which leads to the formation of adhesions between the tendons, ligaments and joint capsule around the shoulder joint over time, resulting in impaired shoulder joint movement. Secondary frozen shoulder: It is mainly induced by long-term fixation after acute trauma to the shoulder and upper limbs, such as clavicle fracture, scapula fracture, humerus fracture, shoulder joint dislocation, rotator cuff rupture, etc. It can also be caused by cervical spondylosis resulting in long-term aseptic inflammation around the shoulder joint that cannot be cured. Currently, the conventional treatment for frozen shoulder is oral anti-inflammatory drug therapy and topical treatment with blood-activating and blood-stasis-removing patches, but due to the long treatment period and poor efficacy, patients should not adhere to the treatment. The pain department has unique advantages in the treatment of such diseases. Through nerve block therapy and lesion injection therapy, the pain department can treat both the symptoms and the root cause with immediate effect. Through the injection method, anti-inflammatory and analgesic drugs are injected directly into the nerve trunk and surrounding tissues to rapidly reduce pain, relax tense muscles, eliminate inflammation and promote the recovery of shoulder joint function.