Swelling of the arm after repositioning of shoulder misalignment may be caused by ligament injury or traumatic frozen shoulder, which can be treated by medication such as sodium salicylate or functional exercises. 1. Ligament injury: When the shoulder is dislocated, the ligaments around the shoulder will suddenly be subjected to more than the limit of pulling and loading, resulting in ligament injury, joint swelling and pain, and activity limitation and other symptoms. It can be treated with anti-inflammatory drugs such as aspirin. 2. Traumatic periarthritis: acute contusion and straining injury of the shoulder may cause traumatic periarthritis, which may cause swelling and pain in the range of the shoulder, and restriction of the range of motion and other symptoms. It can be treated with medication such as aspirin, etc. In addition, it can also be treated through the circle exercise method to restore the function of the shoulder joint. Patients who experience swelling of the arm after repositioning of the shoulder, need to go to the hospital for relevant examinations to clarify the cause of the disease and treat the cause of the disease. If necessary, please consult your doctor for instructions and precautions before using the medicine.