The formation of high and low shoulder may include the following causes, mainly bad habits and physiological development, as follows: 1. Bad habits: It may be caused by some bad habits in childhood, such as improper sitting posture, improper walking posture, which may cause high and low shoulder. 2. Physiological development: It may be caused by physiological development, such as fracture, asymmetric growth and development, which may cause high and low shoulder. There will be a high and low shoulder situation. In the case of idiopathic scoliosis, the scapulae are not at the same level, so the shoulders will be high and low. In addition, some people may be accustomed to using one arm, which may cause atrophy of the muscles on the opposite arm and scapular area, which may cause high and low shoulder.