The common causes of clavicle protruding on one side and not on the other side are bad habits, scoliosis and shoulder lock joint injury. 1. Bad habits: due to their own postural habits, such as shrugging the shoulders to one side, or postural slanting of the neck, can also be seen on one side of the shoulder overstress, such as one shoulder for a long time satchel, shoulder shoulder, shoulder picking heavy objects, resulting in one side of the shoulder to become low, resulting in the two sides of the clavicle appeared obvious asymmetry. After a long time, one side of the clavicle may protrude and the other side may not. 2. Scoliosis: seen in patients with congenital scoliosis, after the scoliosis occurs, it will result in the situation that the high and low shoulders are different, leading to the asymmetry of the clavicles on both sides and the uneven and asymmetric shoulder joints on both sides, which will result in the clavicles protruding on one side and not protruding on the other. 3. Injury to the acromioclavicular joint: After injury, dislocation of the acromioclavicular joint or fracture of the clavicle will easily lead to unevenness of the clavicle, with one side of the clavicle protruding and the other side of the clavicle not protruding. If the fracture heals abnormally at a later stage, resulting in obvious deformity of the clavicle area, it will also cause the clavicle to protrude on one side and not on the other. There may be other reasons for one side of the clavicle protruding and the other side not protruding, so it is recommended to go to the hospital in time and have standardized treatment under the guidance of the doctor.