adult-scoliosis

Adult Scoliosis

By John J. Vaughan, M.D.

Scoliosis is defined as a lateral curvature of the spine. To be considered scoliosis, a spinal curvature must measure greater than 10°. It has been estimated that the number of adults with a curvature greater than 30° in the United States is approximately 500,000.

There are many different causes of scoliosis seen in different age groups. In this article, two common types seen in adults will be discussed: adult idiopathic scoliosis and degenerative scoliosis.

Adult idiopathic scoliosis typically first develops in the teenage years when it is known as adolescent idiopathic scoliosis. By convention, after the age of 18, the “adolescent” becomes “adult.” Idiopathic means the scoliosis is not due to other known causes (congenital, neuromuscular disease, etc.) This type of scoliosis is most frequently seen in the thoracic spine, the lumbar spine, or both.

Degenerative scoliosis, also know as de novo scoliosis, is not present at the time skeletal maturity is reached. It typically develops in the middle and late stages of adult life. This type of scoliosis is felt to be caused by degeneration of the stabilizing structures of the spine, especially the intervertebral discs and the facet joints. As these structures degenerate, they lose their ability to maintain normal alignment of the spine and scoliosis develops. Frequently accompanying this is a condition known as spinal stenosis. This is a pinching of the spinal nerves due to disc protrusions, bone spur formations, and abnormal alignment of the vertebra. Degenerative scoliosis is most frequently seen in the lumbar spine.

The larger the scoliotic curvature in the adult, the greater the chance for progression. Thoracic curvatures greater than 50° and lumbar curvatures greater than 30° have an increased likelihood of progressing through the adult years.

Adults with scoliosis may have complaints of back pain or lower extremity pain as a result of their scoliosis. The back pain may occur because of degenerative arthritis forming in their spine. Buttock and leg pain may result from nerve compression due to spinal stenosis seen in conjunction with scoliosis. Adults may also complain of increasing imbalance, a progressive rib hump, or loss of height.

The non-operative treatment of scoliosis is frequently successful. Physical therapy can be used, and an exercise program directed at spine stabilization instituted. A daily exercise program can decrease pain and improve functions.

Non-steroidal antiflammatory medications are useful in treating adults with scoliosis. They can be helpful in controlling the back and leg pain associated with scoliosis.

Indications for surgical treatment of adult scoliosis include:

• Progressive spinal curvature or spinal imbalance over time.

• Intolerable pain associated with the scoliosis that has been refractory to non-operative measures.

• Large scoliotic curvatures which are likely to progress.

• Neurologic dysfunction causing pain, numbness, or weakness.

Surgery for scoliosis in adults tends to be an extensive and complex procedure. The type of surgery depends on the location of the curve, flexiblity of the curve, age of the patient, need for decompression, and many other factors.

The surgical treatment options for adult scoliosis are varied. They include anterior surgery, posterior surgery, or a combination of both. The surgery commonly involves placement of instrumentation to stabilize the spine and a fusion with bone graft. The instrumentation and fusions may be done either anteriorly or posteriorly. If there is significant spinal stenosis associated with the scoliosis, a decompression of the neural elements is frequently indicated.

Figures 1a and 1b illustrate a 47-year-old patient with adult idiopathic scoliosis who underwent a posterior spinal fusion with instrumentation.
Figure 1a - Pre-operative x-rays demonstrating a pre-operative thoracolumbar scoliosis.
Figure 1b - Post-operative x-rays.

Last Updated: 10/4/03