Why does scoliosis develop most often in late childhood?
And why is it more common in girls? Scoliosis most often develops in late childhood because of the association between growth and progressive scoliosis curves. Although scoliosis can develop at any age, including infantile (age birth- 3), Juvenile (age 3-10), adolescent (age 10-18) and adult (> age 18), the most common time to detect curves are in late childhood/early teen years. Thus, the most common form seen, Adolescent Idiopathic Scoliosis (AIS), is detected between ages 10 and 18, often just before or after puberty and the associated adolescent growth spurt. Small curves (10-20 degrees) are nearly equally found in boys and girls, but larger curves which often need treatment (those > 40 degrees) are seen in females to males in a 9:1 ratio. It is a bit unclear why that is the case, it may certainly be a genetic tendency, and/or something relating to hormonal alterations or connective tissue adaptations for the potential for childbirth in females.
What causes some children to develop scoliosis while others do not?
Is it simply genetic or are there other factors involved? Although there are many potential etiologic factors implicated for idiopathic scoliosis development, the genetic aspects are probably the most influential. Multiple genetic studies have confirmed strong family relations including studies of identical vs paternal twins. Other factors such as various hormones, equilibrium and balance issues have been promoted as well, but none are conclusive. The genetic factors are strong but highly complex, multigene interactions that are still being actively investigated, including here at Washington University by Dr Matt Dobbs of the Department of Orthopedic Surgery.
What causes adults to develop scoliosis?
Adults can develop scoliosis as a result of slow progression of childhood curves that were untreated, or as curves that develop on their own from aging of the spine, usually in the lower (lumbar) region and termed "de novo" adult lumbar scoliosis. These de novo curves result from progressive degeneration of the joints in the back of the spine along with degeneration of the discs supporting the front of the spine. Although this natural aging process occurs in everyone, only certain people will develop a corresponding scoliosis with the process.
At what point is a brace needed to treat scoliosis?
Bracing is indicated only for children and teens that are still growing in order to attempt to slow or stop the scoliosis progression during the remainder of the child's skeletal growth. It is also only indicated for mild to moderate curves in the 20-40 degree range and appears less effective in males and those with larger body habituses.
Beyond bracing, what are the treatment options? Are minimally invasive procedures becoming more common?
There are 3 standard treatments for scoliosis in Children: Observation, Bracing (as above) and surgery. Observation is indicated for small curves (< 20 deg, no matter what the age), and curves < 45-50 degrees in those who are skeletally mature. Surgery is indicated for curves > 40-45 degrees in those with growth remaining, and >45-50 degrees for those who are done growing (skeletally mature). For adult patients, there is really no good indication for bracing except for the rare circumstance of helping patients with lumbar pain, postural changes for temporary pain relief. Observation with physical therapy, aerobic activities etc are indicated for a vast majority of patients with smaller curves and minimal symptoms. Active non-surgical treatment such as epidural steroid or nerve root injections are indicated in the subset of adults who have spinal stenosis (narrowed spinal canal) and/or pinched nerves in the lumbar spine. Surgery is reserved for those adults with previously untreated adolescent scoliosis with continued curve progression in adulthood to curves > 50-60 degrees in the thoracic or lumbar spine, or for those denovo curves > 30-40 degrees in the lumbar spine in which the patient is symptomatic.
Can scoliosis cause related problems with blood flow or organ systems?
Scoliosis can cause restricted pulmonary disease when affecting the thoracic spine, and even suboptimal cardiac function in the very severe curves > 90-100 degrees. For curves affecting the lumbar spine, spinal stenosis and/or pinched nerves can cause lower extremity pain/disability. Also, for those patients whose spine is collapsing, the trunk can shorten with the rib cage resting on the pelvis making breathing more difficult and often impairing GI function as well. Also, the psychosocial aspects of living with a progressive disfiguring spinal deformity cannot be ignored and impaired quality of life parameters are documented in the literature for various subsets of adult scoliosis patients.