From time to time, the National Scoliosis Foundation receives questions from parents about early onset or infantile scoliosis. To find out more about this spinal abnormality, we asked Nancy Schommer, author of Stopping Scoliosis, to interview Dr. Ronald Moskovich, who is Assistant Professor of Orthopedic Surgery at New York University as well as a practicing specialist in spinal disorders at the Hospital for Joint Diseases Orthopaedic Institute in New York City. What follows are excerpts from the interview.
Q: Dr. Moskovich, would you give us a brief overview of early onset scoliosis?
A: It’s important to know that early onset scoliosis is idiopathic, which means we do not know what causes it. Early onset scoliosis occurs before the age of five, and occurs more often in boys than in girls, though we don’t know why. It was formerly referred to as ‘infantile scoliosis’, a term some people still use. It also must be stressed that early onset scoliosis is a very rare condition: the incidence of it is only 1 or 2 per 10,000 people. The vast majority of cases improve spontaneously, which means even fewer need to be treated.
Q: Is early onset scoliosis the same as congenital scoliosis?
A: Not at all. Whereas congenital scoliosis involves a curvature caused by an abnormality such as a hemivertebra or other bone structure problem, early onset scoliosis stems from no known cause-as we’ve said, it’s idiopathic. There is no obvious abnormality in the development of the vertebrae that we can identify in patients who have early onset scoliosis.
Q: How severe must a child’s curvature be before you would define it as an early onset scoliosis?
A: If a child under the age of five has a 10 to 15 degree curve or greater, we would say that child had early onset scoliosis.
Q: Once you’ve identified that the child’s curve is 10 degrees or more, what steps do you take?
A: Of course we would watch the curve closely; we’d also take an x-ray which would alert us to signs of an increased risk of progression. For example, we’d look for a larger curve or marked asymmetry of the ribs, both of which can be signs that a curve may progress. The x-ray could provide us other valuable information as well: whether the child had structural problems indicative of congenital scoliosis, or whether the child had abnormalities of the heart, kidneys, or hips, all of which are more common with early onset scoliosis.
Q: Are any special tests required apart from x-rays?
A: It is important to confirm that the patient is neurologically normal. Examination of the abdominal and plantar reflexes which may alert a physician to subtle neurologic abnormalities should not be neglected. In certain cases, a magnetic resonance imaging (MRI) may be used to evaluate the spinal cord and to exclude neurologic anomalies at the base of the skull if there is any suggestion of neurological problem.
Q: At what point do you begin treatment?
A: If a curve progresses beyond 15 to 20 degrees, we would treat the child by using a plaster cast to keep the curvature from progressing.
Q: Why plaster instead of plastic?
A: There are several reasons of that choice. it can be awfully difficult to keep a young child in a plastic brace which has to be put on and taken off each day. Also, plaster casts are actually more comfortable-they create less pressure on the body because they’re molded to the body. And because plaster casts are generally easier to deal with, we find we get better correction with them. The plaster cast will be changed every 3 to 4 months depending on the growth rate of the child. Plastic bracing is used once initial correction has been achieved or may be used from the outset on larger children.
Q: How successful is plaster casting?
A: Very-about 90-plus percent of patients get better due to casting.
Q: If the curve continues to progress despite the plaster cast, what other treatment options are available?
A: If a curve progresses, we’d do surgery involving an anterior and a posterior fusion.
Q: Why would you have to do two fusions?
A: If you only do a posterior fusion, two things happen: first, it may not fuse, because the back of the spine is the ‘tension’ side of the spine, and bone under tension tends not to heal very well. Second, the front of spine will continue to grow and will twist out, causing the spine to bend backwards into a lordosis.
Q: When surgery is necessary, is it important to fuse patients at the earliest age possible?
A: In many cases, we would try to delay surgery until the child had reached a reasonable size, say at the age of 10, but sometimes that’s not possible, and early surgical treatment is necessary. Also, it is well known that by the age of two, children have reached almost half of their adult spinal growth size. It’s better to have a relatively short, straight spine than a longer, crooked spine.
Q: When a curve is left untreated, what can happen?
A: An untreated curvature can progress rapidly-as much as 40 degrees or more in just months. As the curve progresses, the size of the actual chest cavity can diminish, affecting the developing lungs, which can create respiratory problems for the child that will persist throughout life.
Q: You mentioned earlier that early onset scoliosis is idiopathic-but do you have any thoughts about what might cause this condition?
A: Besides possible heritable factors, there may be an environment trigger. We’re not really sure why, but in low socioeconomic groups in England there’s a greater prevalence of this type of scoliosis, which may be due to post-natal positioning-the way that babies are positioned in their cribs. In England, mothers are taught to lay babies down on their sides. This can cause the spine to sag, and can cause molding of the head and an increased incidence of dislocation of the hip. By contrast, here in North American we tend to put babies down in a prone (face-down) or supine (face-up) position, which results in much more even pressure on the spine.
Q: Based on this knowledge, what do you recommend?
A: In my own practice, I recommend that swaddling babies so that they can’t move and putting babies persistently on one side should be avoided. However, infant positioning should be individualized and one should consult their pediatrician.
Q: Any other advice?
A: If there’s a family history of scoliosis, make sure the family pediatrician carefully examines the child: check for asymmetries. As with all types of idiopathic scoliosis, early detection and early treatment are imperative.