By Nancy Schommer,
author of Stopping Scoliosis
In response to many questions the National Scoliosis
Foundation has received about congenital scoliosis, we recently
interviewed Dr. Robert B. Winter of the Minnesota Spine
Center, Minneapolis, a founder and past president of the
Scoliosis Research Society.
Q: Dr. Winter, would you begin by providing us with a definition
of congenital scoliosis?
A: Doctors would describe it as a condition due to congenitally
anomalous vertebral development, but it's easier to say
it is a curvature of the spine caused by birth defects in
the spine itself.
Q: What sorts of birth defects cause congenital scoliosis?
A: The most common birth defect is called hemivertebra,
which means half of one side of a vertebra forms while the
other side doesn't. Another defect is called a unilateral
bar, a condition where you will find three to four vertebrae
"stuck"or fused together on one side. At present,
no one knows what causes these defects.
Q: In the case of a hemivertebra, how does it create a
curvature?
A: All growing bones have growth centers, but if you're
born with half a bone on one side and the other side is
missing, the side with the growth center will grow faster
than the other, and you end up with a curvature.
Q: Does congential scoliosis occur more often in girls
than in boys?
A: Yes, it occurs about 60% of the time in girls, 40% in
boys. We do not know why this is so.
Q: When are doctors most likely to see signs of congenital
scoliosis in children?
A: We seldom see it at birth unless an x-ray has been taken
for some other purpose, such as pneumonia, or unless the
child is born crooked. I have seen a few children
a week old who had 40º-50º curves, but that's fairly rare.
More than likely, we'll see it show up later in life—for
example, in a teenager who's going through the growth spurt.
Q; In the case of the teenager, how would you know the
youngster had congenital scoliosis and not idiopathic scoliosis?
A: When you look at an x-ray and see abnormal bone, you
know it's congenital. With idiopathic scoliosis, you
won't see any abnormal bone. As your readers will
recall, idiopathic means a disorder that has no known
cause.
Q: How many individuals in the U.S. population are affected
by congenital scoliosis?
A: Congenital scoliosis is not a common problem:
approximately one person in every 10,000 is affected, and
that number has remained fairly stable over the years.
Q: Do congenital curves always worsen?
A: No. A smaller number—only about 1%-2% of congenital
curves—will get better by themselves. Another 5% stay
right where they are and never require treatment, though
we will monitor these twice a year with x-rays to make sure
they've stabilized. Roughly 75% do worsen and require
treatment.
Q: How far would a congenital curve have to progress for
you to begin thinking about treating it?
A: There is no magic number of degrees—quite different
from idiopathic. If it's progressing, it needs treatment!
Q: Would you tell us about the treatments that are available
for those whose curves get to that point?
A: Treatment of congenital is quite different from treatment
of idiopathic scoliosis. For example, with congenital, bracing
seldom works; the bones themselves are crooked or deformed,
and a brace on the outside simply can't affect a discrepancy
on one side or the other of the vertebral column.
The only treatment that works is surgery.
Q; Tell us about the surgical techniques.
A: As I've said, with congenital scoliosis, one side of
the spine is growing faster than the other, so to solve
the problem—since we cannot put growth tissue in a place
where it doesn't exist—we do anterior (front) and/or posterior
(back) "growth arrest" surgery. Basically, this means
we fuse the outside, or convex, side of the curve, perhaps
4-5 vertebrae in all. By doing this, we stop the growth
in the fused area.
Q: How does this affect a child's future growth?
A: It will affect future growth, but remember—the right
surgery at the right age will give children taller spines
than they would have had without surgery.
Q: Do surgical patients usually wear a postsurgical brace
or cast?
A: Because we're fusing a portion of the spine, and we're
not usually inserting rods and/or wires that would help
stabilize the healing spine—we really must have these
patients wear post-surgical braces or casts for protection.
Q: What is the likelihood of a surgical patient having
to undergo more surgery later in life?
A: Two-thirds of the time, one early surgery solves the
problem and the child will bounce back with incredible speed
and grow up well after the problem is solved. Roughly
33% of the time, there will be an additional operation.
Q: Do the alcohol or drug habits of parents cause congenital
scoliosis?
A: We are starting to see some cocaine babies with congenital
abnormalities, but at our Center, we haven't seen any congenital
scoliosis that appears to be related to, say, marijuana
or heroine use, or alcohol abuse.
Q: Is congenital scoliosis hereditary?
A: Ironically, congenital is much less hereditary than
idiopathic scoliosis, but we don't know why. One of
our surveys of 1,200 patients from our clinic showed there
were only 12 hereditary situations. Interestingly,
in identical twins it's extraordinarily unusual for both
twins to have it; it's more common that one would have it
and the other wouldn't.
A: Do you expect the treatment of congenital scoliosis
to change or improve in the future?
A: In the last 10 years we've seen an explosion of better
surgeries for these individuals. In my training period,
for example, all you could do was a fusion, but now you
can actually take out the hemivertebra and do a local correction.
That used to be considered dangerous, but with recent advances
with spinal cord monitoring and other techniques, it's a
fairly common and quite safe procedure.
Q: Are there any prenatal tests that will pick up signs
of congenital scoliosis?
A: At our Center, we've seen only one child whose congenital
scoliosis was picked up on ultrasound, but that's pretty
rare. Unfortunately, congenital scoliosis defects
are subtle—there's so much cartilage relative to the amount
of bone that the anomalies simply don't show up.
Q: What other problems might one find in conjunction with
congenital scoliosis?
A: Congenital scoliosis patients tend to have other problems
as well, such as kidney dysfunctions or urinary tract abnormalities.
In fact, 25%-30% of patients have kidney-bladder problems
as well. 40% of patients have other anomalies of spinal
cord development. 10% have congenital heart problems.
Q: Is there pain associated with congenital scoliosis?
A: No.
Q: Can physical therapy help reduce or stabilize a congenital
curvature?
A: This has been tried, but no, it doesn't help at all.
Q: Are there any signs that parents might look for?
A: There may be signs such as a rib hump or a small "bump"
on the back. There may be foot problems, such as a
clubfoot, which could be a tip off. Quite commonly,
one will find a hair patch somewhere along the spine.
If you notice any of these signs, take your child to a scoliosis
specialist immediately.
