Scoliosis

By Edward S. Pratt, M.D., M.B.A.

The word scoliosis means curved spine. In truth, the spine has several normal curves, most of which are best seen by looking from the side. The neck has a gentle backward curve called the cervical lordosis, the upper back has a gentle forward curve between the shoulder blades called the thoracic kyphosis, and the lower back has a gentle “swayback” curve called the lumbar lordosis. When there is an obvious side to side curve (greater than 10 degrees) we call this scoliosis. It can occur in the upper (thoracic) spine, the lower (lumbar) spine or combinations of both. Usually, when the spine develops an abnormal curve it will also twist. This is what creates the characteristic rib hump or prominence of the rib cage seen with many curves on the right side of the spine with forward bending. Scoliosis can occur in newborn, (congenital form), in young children, (juvenile form), and in older children, (adolescent form). Scoliosis is much more common in girls, but does occur from time to time in boys. In general the earlier scoliosis develops, the more likely it is to get worse; and because it often progresses, the later it is diagnosed the more severe the curve and the more involved the treatment.

Scoliosis can often be suspected from a simple “forward bending test” that every mother or father ought to do on every child yearly from the age of about eight or nine through the age of thirteen or fourteen. The forward bending test is done by sitting in a chair with your child standing in front of you turned away with his or her back toward you. Have your child gradually bend forward and touch his or her toes while you hold the pelvis stable, then gradually return to a standing position. During this maneuver look closely along the spine. The spine and ribs should be symmetrical, of equal fullness, on the left and right. The spine should be straight without any evidence of curve. A scoliotic curve will be most obvious in this forward bent position, and will usually show as a “rib” hump (actually all of the ribs where the spine is curved) that sticks up on the right side, or a fullness or enlargement of the muscles along the spine on one side or the other. If any of these abnormalities are found or even suspected, an immediate referral to your pediatrician or an orthopaedic spine specialist is in order.

Scoliosis can occur in conjunction with many very serious diseases such as tumors, neurological degenerative diseases, spinal cord trauma, and various birth defects, however by far the most common for of scoliosis is called idiopathic, (not associated with any other problem). The purpose of the initial exam is largely to check for associated diseases, and to measure the severity of the curve.

Scoliosis is treated in different ways depending on the severity of the curvature. Mild curves, those less than 20 degrees, are only observed over time for signs of progression. These kids need not change anything they do day in and day out, and receive X-rays every six months or so. We become more concerned around active growth spurts when these curves most commonly progress. Moderate curves, those between 20 degrees and 45 degrees, must be placed in a scoliosis brace. The brace type and the hours per day a child must wear it will vary based upon the curve configuration and the skeletal maturity of the child. As a rule, bracing is not intended, nor is it successful in decreasing the severity of a curve. Rather, bracing can if successful, prevent progression of a curve in growing children. The vast majority of curves that remain less than 45 degrees by the time a child reaches skeletal maturity will not progress during adulthood, while those that exceed 45 degrees usually do. The role therefore of any bracing program is to slow or stop curve progression such that no curve exceeds 45 degrees before skeletal maturity is reached and the brace is discontinued. Most if not all curves that exceed 45 degrees must be considered for surgical correction and fusion.

Scoliosis fusion is sometimes accomplished through the back, sometimes through the side, and occasionally through both approaches. The best approach is influenced by the age of the child, curve pattern, and the curve severity. There are many additional factors your doctor will need to consider here, and the final decision of the physician is usually made with a great deal of deliberation. The surgery consists of placing two rods in the spine spanning the curve and securing them to the vertebrae with screws or hooks. This construct of rods, hooks and screws is then rotated and extended or compressed to straighten the scoliosis and recreate as closely as possible the normal curves of the spine. The area from the top to the bottom of the rod is then roughened and packed with bone graft, in an effort to convert the once mobile vertebral segments into a solid fused sheet of bone. Once fused solid, the curves usually will not progress or change over a lifetime. Occasionally, 10% of the time, a gap in the fusion can develop (pseudoarthrosis) and further surgery may be required to obtain solid fusion. Other possible complications associated with surgery include blood clots in the legs or lungs, pneumonia, infection, reaction to blood products, neurologic injury, and dislodgement of the hooks and rods. These additional risks are unusual, less than 1-3% taken in total. Youngsters rebound very fast after major surgery, but even so, expect 4 to 6 weeks before energy levels come back to normal. Lastly, although this surgery will effectively correct the majority of a scoliotic curve, it will never correct it all. In addition, the remaining movable segments above and below the fusion often undergo added stresses through life, frequently developing premature arthritis, instability or both.