1, local pain: you will feel severe pain immediately, especially when the wormwood ball hits the bone directly.

2. Subcutaneous hemorrhage: A large or angular wormwood ball will lead to subcutaneous hemorrhage around the scapula, forming ecchymosis or hematoma.

3, muscle strain: improper force or the weight of wormwood ball is too heavy, which will lead to muscle strain, causing shoulder pain, swelling, limited activity and other symptoms.