Due to the hollow joint cavity, there is no humeral head and the shoulder peak protrudes, forming a typical square shoulder deformity. Square shoulder deformity occurs in shoulder joint tuberculosis. Shoulder tuberculosis is relatively uncommon, accounting for only 1.06% of systemic osteoarticular tuberculosis, and is more common in adults than in children (Turek, 1977), with the most frequent cases occurring between the ages of 21 and 30. Most of them are in young adults, and patients mostly suffer from active tuberculosis at the same time. Gender, slightly higher in males than females. The left side is slightly more common than the right side. Therefore, the focus of square shoulder deformity prevention is to control and prevent tuberculosis infection. 1.Early diagnosis and treatment: If you have tuberculosis, you should be diagnosed and treated early to avoid deterioration and prevent spreading of the disease; tuberculosis patients can go to any chest clinic for treatment. 2.Screening for people who have had close contact with TB patients: This is mainly for family members of the patient, including tuberculin tests and/or lung examinations for young children and lung examinations for older children and adults. 3. Healthy living: TB bacilli cause disease when the body’s resistance decreases, so it is important to maintain a healthy lifestyle to reduce the chance of developing the disease, including: moderate exercise, adequate sleep, balanced diet, avoidance of alcohol and tobacco, fresh air, indoor air circulation, and personal hygiene. For example, avoid coughing or sneezing in front of others. 4. BCG vaccination: The Chest Division of the Department of Health provides BCG vaccination to all newborns in Hong Kong; for children under 15 living in Hong Kong who have never received BCG vaccination, they are also recommended to receive this vaccination.