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
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.