Shoulder periarthritis, abbreviated as frozen shoulder, is a common disease characterized by pain and limitation of movement around the shoulder (including the upper extremity, back and neck). In our outpatient clinic, we have treated 120 patients since 2004 with sodium vitreous acid shoulder joint cavity injection and local closure with tretinoin, and achieved good results. The results are reported as follows. 1.1 Data and methods 1.1 Clinical data Among the 120 cases in this group, 34 were male and 86 were female, aged 41-68 years old, with an average of 55 years old. The causes of onset were: 23 cases with a clear history of trauma, 67 cases with long-term shoulder strain, and 30 cases without a clear cause. All of them were patients seen in our hospital and met the diagnostic criteria of frozen shoulder. All cases had routine blood, biochemistry, blood sedimentation, rheumatic series, HLA-B27 and X-ray examination to exclude shoulder pain caused by tumor, fracture, dislocation, etc. or other arthritic shoulder damage, etc. 1.2 Treatment The patient was placed in a sitting position with the shoulder joint naturally drooping. The pain point and shoulder puncture point (1 cm below the rostral process) were selected and marked, and routinely disinfected with iodine and alcohol. Hold a syringe with a No. 7 needle and puncture into the shoulder joint cavity. After successful injection of sodium vitrate (Shandong Zhengda Forida Pharmaceutical Company, specification: 2ml, 20mg), then inject 1ml of tretinoin + 1ml of lidocaine at the painful point for local closure once a week for 3-4 weeks. The next day after the injection, the patient was asked to do activities in all directions of the shoulder joint, such as bending in circles, climbing the wall with fingers, spreading the wings of the arms, and lifting the shoulder with the skids, etc., with the amplitude from small to large and the time from short to long, with a follow-up of 1 year or more. 1.3 Judgment of efficacy Patients were evaluated according to their conscious symptoms and clinical signs before receiving treatment, at the end of one course of treatment and at the follow-up visit. Cured: the shoulder joint pain disappeared and the activities of daily life were normal; improved: the pain basically disappeared and the activities of daily life were basically normal. Ineffective: Shoulder pain and restricted activities. 2.Results After one course of treatment, according to the efficacy evaluation method, 81.67% of the cases were cured, 13.33% were improved and 5% were invalid, with a total effective rate of 95%. The cause of frozen shoulder is not completely clear. The chronic injury to the shoulder joint caused by the degeneration of soft tissues in middle-aged and elderly people, combined with long-term repeated excessive activities, poor posture and trauma, causes secondary atrophy and adhesion of the shoulder capsule wall, intracapsular tendons and periacetabular tissues. In particular, subacromial bursitis, supraspinatus, and biceps long head tenosynovitis. There are two theories of pathogenesis: one is the theory of proteoglycan metabolic changes. Proteoglycan is the matrix of connective tissue and the main component of the joint fluid, with vitronectin, chondroitin sulfate, heparin, keratin sulfate and other substances, which have the ability to increase tissue resistance to allergy, anti-inflammation and injury. The proteoglycans located within the synovial fluid in the joint capsule, bursa and tendon sheath have lubricating, cushioning and anti-adhesive effects. The metabolic changes of proteoglycans are closely related to age. When the proteoglycan content changes with age, it can cause bone growth, aseptic inflammation of the synovial membrane and synovial bursa of the shoulder joint, degeneration, adhesion and calcification of the ligaments and tendons around the shoulder joint and produce pain and affect joint movement, thus leading to the occurrence of frozen shoulder. The second is the theory of local microcirculatory disorders. Under the action of trauma and chronic strain, some of the muscle fibers or ligaments around the shoulder tear, causing local bleeding and edema, resulting in local blood circulation obstruction, causing tissue cell hypoxia and accumulation of metabolic products and inflammatory substances, which further stimulates muscle and vascular contraction and aggravates the local microcirculation obstruction, resulting in tissue degeneration, edema, joint adhesion and stiffness, and eventually leading to the occurrence of periarthritis of the shoulder. Sodium vitrate is a large mucopolysaccharide, an important component of synovial fluid and cartilage matrix, produced and secreted by synovial B cells and mononuclear giant eosinophils. Sodium vitrate can combine with glycoproteins to attach to the surface of articular cartilage to protect it, combine with proteins and free in the joint fluid to play a lubricating role, regulate the viscoelasticity in the joint, and play an important role in maintaining joint function. negative charge, has an inhibitory effect on negatively charged fibroblasts, and has a good anti-inflammatory effect, which reduces the release of fibroblast-stimulating factors and promotes tissue repair of wounds. In addition, the drug has a molecular sieve effect, which prevents endotoxins, immune complexes and inflammatory transmitters from entering the joint cavity and inhibits the release of painful substances such as bradykinin for analgesic purposes. Trimethoprim is a long-acting glucocorticoid preparation with the characteristics of fast onset, high efficacy and long duration. It can inhibit synovial tissue synthesis of IL-8 and TNF-α, produce strong anti-inflammatory and analgesic effects by inhibiting the proliferation of capillaries and fibroblasts, reducing collagen deposition, inhibiting granulation tissue formation and reducing local scarring and adhesions caused by inflammation, and can quickly eliminate swelling and pain and improve symptoms. Traditional pain closure can only relieve pain, but cannot improve shoulder joint mobility and healing often leaves partial shoulder joint dysfunction, but with sodium glacial joint cavity injection, not only can relieve pain as soon as possible, but also can improve the inflammatory response of synovial tissue, increase joint mobility, enhance patient’s self-confidence and ensure early shoulder joint function exercise, which greatly improves patient’s quality of life. It improves the efficacy of the treatment and reduces the patient’s pain and dysfunction, which is an effective treatment for frozen shoulder.