Scoliosis is the lateral curvature of the spine wherein it bends either to the left or right side. It can develop in various locations in the spine such as in the thoracic (middle spine), thoracolumbar (midway between the upper and lower back) or lumbar (lower back) area.

In almost 85% of the cases of scoliosis, there is no known cause and categorized as idiopathic. Nevertheless, the remaining 15% falls into two major causes of scoliosis: functional and structural.

Functional or non-structural

This type of scoliosis is only a temporary condition wherein the spine is considered structurally normal before the curvature developed. It is a functional type of scoliosis because the root cause is another problem outside the spine. For instance, muscle spasms can cause the spine to bend, but when the spasms are relieved, the scoliosis is also corrected. Appendicitis can also cause functional scoliosis as the leg is pulled to towards the abdomen to relieve pain.


Structural scoliosis is the presence of real structural deformity in the spine. It can be possibly caused by metabolic diseases, muscular dystrophy, birth defect (congenital scoliosis), connective tissue disorders or Marfan’s syndrome leading to problems in the musculoskeletal system. Among the 15% of cases with known cause, neuromuscular conditions such as muscular dystrophy and cerebral palsy constitute 20% of the causes of scoliosis. These muscular conditions prevent the spine from growing normally because the child cannot stand straight in the first place.

Aside from the above causes categorized into structural or functional, other possible causes of scoliosis identified include the following:

  • Bad posture

Poor posture is also seen as a possible cause of scoliosis. When the person does not stand up or sit erect, the spine may bend because of the increased spasms of the muscles.

  • Carrying heavy loads in one side of the shoulders

Carrying heavy bags or loads in one side for prolonged periods can also contribute to the occurrence of scoliosis as a result of uneven weight bearing of the spine on the other side.

  • Differences in leg length

Those with different leg lengths are also seen to increase the risk of scoliosis.

  • Genetics

Genetics may also play a role in the development of scoliosis because it was observed to run in families. The genes CHD7 and MATN1 are believed to be affected in those with idiopathic scoliosis.

  • Infection and injuries in the spine

The presence of direct physical injury and infections in the spine are also other possible causes of scoliosis because these can lead to direct damages in the connective tissues that hold the spine in an erect position.

Other risk factors include age since the symptoms usually start at the onset of puberty increasing the risk of pre-pubertal teens in developing the condition. Gender is also another risk factor because females have higher cases of the condition and higher risks for worsening condition.

Despite the various possible causes of scoliosis, there seems to be no consensus among experts on the exact cause of the condition. Genetics has remained to be a widely accepted factor on the development of the condition.