Physical Abnormalities. Researchers are investigating possible physical abnormalities that may cause imbalances in bones or muscles that would lead to scoliosis. Some research suggests that imbalances in the muscles around the vertebrae may make children susceptible to spinal distortions as they grow.
Problems in Coordination. Some experts are looking at inherited defects in perception or coordination that may cause unusual growth in the spine of some children with scoliosis.
Other Biological Factors. Several other biological factors are being investigated for some contribution to scoliosis:
- Elevated levels of the enzyme matrix metalloproteinases may cause abnormalities in components in the spinal disks, contributing to disk degeneration.
- Abnormalities in a protein called platelet calmodulin that binds to calcium. This protein acts like a tiny muscle and pulls clots together.
In 80% of patients, the cause of scoliosis is unknown. Such cases are called idiopathic scoliosis. (Idiopathic means without a known cause.) Idiopathic scoliosis may be due to multiple, poorly understood inherited factors, most likely from the mother's side. However, the severity often varies widely among family members who have the condition, suggesting that other factors must be present.
Idiopathic scoliosis may be classified based on age of presentation. Age of onset may also determine the treatment approach. The classification is as follows:
- Infantile: Up to 3 years old
- Juvenile: Four to 9 years old
- Adolescent: Ten years old through the teen years
Idiopathic scoliosis may be initially diagnosed in adults during evaluation for other back complaints or disorders, although the curve is unlikely to be significant.
Congenital scoliosis is caused by inborn spinal deformities that may result in absent or fused vertebrae. Kidney problems, particularly having only one kidney, often coincide with congenital scoliosis. The condition usually becomes evident at either age 2 or in children ages 8 - 13 as the spine begins to grow more quickly, putting additional stress on the abnormal vertebrae. It is essential to diagnose and monitor such curvatures as early as possible, since they can progress quickly. Early surgical treatment -- before age 5 -- may be important in many of these patients to prevent serious complications.
Review Date: 04/06/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.