Scoliosis is defined as a lateral (side-to-side) curvature of the spine. In reality, scoliosis is a three dimensional deformity with vertebral rotation, in addition to side-to-side bending. There are many known causes of scoliosis, including birth defects of the spinal column (congenital scoliosis) and various neuromuscular disorders such as cerebral palsy, muscular dystrophy, and spina bifida. There are also unusual forms of scoliosis caused by injury, tumors, infection, radiation, and metabolic disorders.
The most common type of scoliosis, however, is termed "idiopathic scoliosis," which means there is no known cause. Idiopathic scoliosis may develop at any age during childhood, but most commonly occurs just prior to or during puberty. With the exception of rare forms of scoliosis caused by tumor or infection, scoliosis is not typically a painful condition. Scoliosis is usually detected by school screening, routine physical exam, or by parents. The prevalence of scoliosis (curves greater than 10 degrees) in school screening studies is between 1.3 and 3.0%. Scoliosis curves are measured in degrees, as determined on standing x-rays of the spine. Once scoliosis has been detected, treatment options include observation, bracing, and surgery. Fortunately, most patients with scoliosis require no treatment other than periodic observation. Observation is usually appropriate for curves up to 25 degrees. If a curve measures more than 25 degrees, but less than 40 degrees, and the child is still growing, a brace is usually prescribed. Controlled studies have shown bracing to be approximately 70% effective in preventing the scoliosis from getting worse and requiring surgery. The two most important factors that determine the risk for a curve getting worse are: (1) the amount of growth remaining and (2) the severity of the curvature. In others words, skeletally immature patients are at a greater risk than more mature patients for curve progression and larger curves are more likely to get worse than smaller curves. Surgery is often necessary if the scoliosis is greater than 40 degrees in a growing child. Modern surgical techniques allow for excellent correction of the spinal deformity and rapid return to activities. With recent surgical implant designs, most patients can be walking almost immediately after surgery without a cast or brace. Return to full activity, including sports, is often allowed at six to nine months after surgery. Extensive research is ongoing to determine the cause (or causes) of idiopathic scoliosis. At the present time these is no known cause, hence there is no cure or prevention. Treatment therefore hinges on early detection and close monitoring so that small curves can be prevented from becoming large curves that may require surgery.
Scoliosis in the Adult
Adults with scoliosis (lateral curvature of the spine) fall into two main categories: those who had scoliosis as a child or adolescent and those who develop scoliosis after skeletal maturity. The latter group consists primarily of patients who develop scoliosis of the lumbar spine (lower back) secondary to degenerative disc disease.
Scoliosis occurs in roughly 4% of the adult population. Approximately 85% of these adults have idiopathic scoliosis that occurred during the growing years. Most of the remaining 15% have degenerative scoliosis that developed after skeletal maturity.
Scoliosis can get worse during adult years. Curves under 30 degrees are unlikely to progress after skeletal maturity. On the other hand, large curves can gradually get worse. For example, thoracic curves between 50 degrees and 75 degrees progress an average of 1 degree per year. Degenerative curves have been found to progress by an average of 3 degrees per year. Patients with scoliosis and osteoporosis are more likely to have progression of their curves.
What are the signs that a spinal deformity in an adult is getting worse? An adult with progressive scoliosis may notice a loss of height, a change in waistline, leaning more to one side, an enlarging hump on the back, or a change in the way clothes fit. The definitive way to determine whether or not a curve is progressing is to compare x-rays taken over a period of time.
Most adult patients who seek medical attention for scoliosis do so because of pain, worsening deformity, or both. Pain patterns vary. Many patients have pain that is unrelated to their scoliosis. Treatment for these patients is the same as for any other patient with back pain. Pain caused by the scoliosis may be secondary to muscle fatigue, trunk imbalance, degenerative arthritis or nerve compression. Determining if a patient's pain is caused by the scoliosis requires a careful history and physical examination, as well as a variety of diagnostic studies.
Patients with painful scoliosis but no documented curve progression should be managed nonoperatively initially. Treatment may include medication, physical therapy, manipulation, exercise, weight loss, and activity modifications. For older patients who are not considered to be surgical candidates, bracing may be effective for relief of pain not responsive to these other measures. Adult patients cannot expect permanent correction of their deformity with bracing, however.
The indications for surgical treatment of adult scoliosis include curve progression, pain in the area of the spinal curvature not responsive to nonsurgical treatment, loss of neurological function, and in rare cases of severe thoracic scoliosis, respiratory problems.
When compared to surgical treatment of scoliosis in adolescents, surgery in adults is much more challenging with a greater risk of complications. The reasons for this include osteoporosis, stiffer spines, underlying medical problems, and more extensive surgery. Surgical treatment of adult scoliosis should be approached cautiously with a realistic understanding of the expected benefits, as well as the potential complications. Studies have shown that approximately 85% of adult patients with scoliosis and back pain are satisfied with their results after surgery. A successful result following surgery depends on careful patient selection, meticulous preoperative planning, expert surgical techniques, and diligent post-operative care. Few patients are absolutely pain free after surgery, but most are gratified with their reduced level of pain and increased level of activities.
School Screening for Scoliosis -- Is It Worthwhile?
Scoliosis is an abnormal lateral curvature of the spine. It occurs in approximately 2% of the U.S. population. School screening for scoliosis is a process by which students in the age groups considered to be at risk are examined by a school nurse for signs that would suggest the presence of scoliosis. Screening for scoliosis had been practiced in the United States for over thirty years. The value of school screening, however, is still questioned by some. Those who argue against school screening state that the yield rate is too low to justify the cost. They also argue that the screening methods are too sensitive and therefore result in the referral of too many children that do not actually have scoliosis. Fewer than one out of every 400 children screened for scoliosis actually require treatment.
On the other hand, the majority of spine specialists are in favor of school screening for scoliosis. The following is the position statement issued jointly by the American Academy of Orthopaedic Surgeons and the Scoliosis Research Society: " The purpose of school screening for scoliosis is to detect scoliosis at an early state when deformity is mild and likely to otherwise go unnoticed. It is at this early stage that bracing programs may be effective in halting the progression of the deformity and thus prevent the need for surgical treatment. In addition, the children with more significant scoliosis who often have no other symptoms may be detected at a time when surgical treatment is more effective." It is now well proven that bracing is effective (approximately 70% of the time) in preventing small curves from becoming large enough to require surgery. Currently the best method of detecting these small curves is through school screening. In recent years efforts have been made to make the school screening process more selective for those children with true spinal deformity and thus reduce the number of children referred unnecessarily. Since a single scoliosis operation may cost thousands of dollars in total medical expenses, it would appear that current scoliosis screening programs are cost effective. Even if these programs cannot be proven to be cost effective in strictly epidemiological terms, isn't it worth it if children are spared unnecessary surgery?
In conclusion, there are those who question the value of school screening programs, yet there is no solid evidence that is should be discontinued. Since it is now well proven that bracing can be effective if curves are detected early, we should not abandon the most effective means for such early detection.