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A normal spine, when viewed from behind, looks straight. But a spine affected by scoliosis shows a side-to-side curvature, with the spine looking like an “S” or “C.” The back bones (vertebrae) may also be rotated. This makes it look like the person is leaning to one side. Scoliosis is defined as a curvature of the spine measuring 10° or greater.

Scoliosis is not due to poor posture.

Spinal curvature from scoliosis may occur on the right, left, or both sides of the spine. Both the middle (thoracic) and lower (lumbar) spine may be affected by scoliosis.

What causes scoliosis?

In most cases, the cause of scoliosis is not known. This is called idiopathic scoliosis. In other cases, scoliosis may be caused by a breakdown of the spinal discs. This can occur with arthritis or osteoporosis. Or it may be a hereditary condition that runs in families.

The abnormal curves of the spine are defined according to their cause, including:

  • Nonstructural scoliosis. This is also called functional scoliosis. In this condition, a normal spine is curved due to 1 or more problems. For example, the leg lengths may be different. Or there may be an inflammatory problem. This type of scoliosis is often short-term. It goes away when the underlying problem is treated.
  • Structural scoliosis. The possible causes of structural scoliosis include:
    • Unknown (idiopathic scoliosis)
    • Disease that is neuromuscular, metabolic, rheumatoid, or other type
    • Birth defect
    • Injury
    • Infection
    • Abnormal growth

For more information or to schedule an appointment, call:

  • SBL Bonutti Clinic at 217 342-3400, or
  • SBL Orthopedics & Sports Medicine at 217 238-3435

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