The causes of scoliosis are unknown. However, at the origin of scoliosis, there are three main categories:

1. Neuromuscular: In this case, the deformity of scoliosis occurs in patients with pathologies of neurological or musculoskeletal origin, such as in myelomeningocele, muscular dystrophy, cerebral palsy, muscular dystrophies or asymmetry in the length of the pelvic extremities. In these cases, most people present asymmetry in the length of the pelvic extremities, mainly less than 1 cm, which does not influence the development of scoliosis. And when it develops, the asymmetry is usually greater than two centimeters.

The presence of scoliosis of neuromuscular origin is the result of an imbalance muscle and the consequent loss of control of the trunk. In this type of scoliosis, you can find structured and unstructured curves.

Unstructured scoliosis does not have a rotational component in these cases and may be related to postural defects in adolescents, unlike more than two centimeters in limb length, or with the presence of pain (in these cases it is called analgesic scoliosis); it can be found in cases of lung infection or empyema.

In most cases of neuromuscular scoliosis, the patient regularly has other symptoms of the underlying disease, which help to clarify the diagnosis.

2. Congenital: This type of scoliosis results from asymmetry in the development of the vertebrae, secondary to congenital anomalies (hemivertebrae, segmentation faults). This type of scoliosis usually manifests in young children or before adolescence.
3. Idiopathic: A scoliosis is thus defined where no specific cause is found to explain the development of the deformity. It is regularly an exclusion diagnosis, that means when other origins of the pathology have been ruled out.

There are several types of scoliosis based on cause and age when the curvature develops. Scoliosis is twice more common in girls than in boys. It can be seen at any age, but it is more common after 10 years. Scoliosis is often hereditary, however, there is no correlation in the severity of the curvature from one generation to the next.

There are other possible causes of scoliosis that include spine tumors such as bone osteoma. This is a benign tumor that can appear in the spine and produces pain that causes the person to lean towards the opposite side of the tumor, to relieve the pressure on it and, consequently, the pain. This effort can produce a deformity of the spine.