Two bones protruding in the back may be hunchback (a form of posterior protrusion of the thoracic vertebrae), but it is not absolute, and it may also be winged shoulder, trauma, or congenital skeletal developmental abnormality. 1. Hunchback: People with a hunchback usually have a posterior protrusion of the thoracic spine, which can lead to a posterior protrusion of the shoulder blades, producing the symptom of two bones protruding from the back. 2. Winged shoulder: if there is a central nervous system lesion, resulting in increased muscle tone or local muscle weakness in the scapula area, resulting in the phenomenon of protruding two bones in the back, which is not a symptom of hunchback. 3. Trauma: In the position of scapula in the back, if the impact of external force leads to local injury, such as fracture, it may produce changes in the bone structure, resulting in the phenomenon of two protruding bones in the back. 4. Congenital bone development abnormality: some people have abnormal bone development due to congenital factors, such as abnormal structure of thoracic vertebrae or scapula. If the two bones in the back are protruding, we need to find out the cause, and if there are obvious structural problems, we need to choose the treatment plan under the guidance of the doctor according to the cause and severity of the disease.