Spine I: Staying Out of Trouble with Scoliosis in Children

Asking why the child came to see you often brings out
important information— that a family member may have scoliosis, or the
child is complaining of back pain, etc. Often the referring doctor’s
diagnosis of scoliosis is not what is bothering the patient. If a
family member is said to have scoliosis, a quick Adams forward bending
test of the family member provides useful information. It gives the
surgeon more confidence that the patient’s scoliosis is more likely to
be idiopathic, though Dr. Emans points out the pitfall of incorrectly
assuming the child has AIS. We still must look for other causes of
scoliosis in the child. Looking at the parent is useful for explaining
the consequences of mild disease and usually makes the family member
feel better when you rule out significant scoliosis. Epidemiologic
studies tell us that back pain in early adolescents begins to approach
that seen in adults, so this should not raise a red flag unless it is
abnormal pain (positive finger test, night pain, pain which is not
activity related, etc.; see Chapter 20 on back
pain). Of adolescents with known idiopathic scoliosis, 23% present with
back pain, and 9% complain of back pain during the course of
observation.¹

Significant scoliosis may not be appreciated when the
patient is standing. This is particularly true in double major curves,
in which curves over 50 degrees may add up to a rather straight torso (Fig. 19-10).
The rotational asymmetry of the spine, however, will be easily
appreciated in the Adam’s forward bending position. Stay out of trouble
by never considering an examination of the spine to have been done
unless rotational asymmetry has been evaluated. If on Adam’s forward
bending test the prominence is on the “wrong” side (curve concavity)
the curve is usually not structural, but compensatory for a leg length
discrepancy. A quick way to test for pelvic obliquity, which is most
often caused by a leg length discrepancy, is by placing the examiner’s
fingers on the iliac crests (see Fig. 19-7B).
Pelvic asymmetry may result from causes other than a leg length
discrepancy such as a dislocated hip, hip abduction or adduction
contractures, or previous Salter osteotomy. For significant pelvic
obliquity in the standing patient, a scanogram may provide more
information. And, of course, the importance of a neurologic examination
in evaluation of the patient with scoliosis cannot be overemphasized
(see Chapter 2, 60 Second Neuro Exam).

Standing radiographs show a greater magnitude of
scoliosis than supine radiographs. Do not mistake this for progression.
You can verify the patient is standing by the air bubble in the
stomach, which is flat on the bottom (see Figs. 19-2, 19-5A, and 19-8).
When lateral radiographs are taken, if patients hold their arms
straight out in front of them (parallel to the floor) as appears to be
the standard

teaching
for radiology technicians, this results in a sagittal vertical axis
that is at least 3 to 4 cm more posterior than normal, and likely
changes the kyphosis and lordosis as well.²
By having the patients place their hands on their shoulders, with their
elbows pointing forwards, the arms will not be superimposed on the
spine, and the effect on sagittal contour will be minimalized. Bending
films can produce highly variable results depending on how they are
done (Fig. 19-11). Bending radiographs taken
supine or over a bolster will most likely demonstrate much less
curvature than standing radiographs. Explain to parents at the first
visit that there is up to 7 degrees of measurement error in
determination of the Cobb angle, so that parental focus on minor
changes of Cobb angle, and many minutes of discussion, could be avoided
in the future. In children ≤10 years of age with scoliosis in the range
of 20 degrees or greater, an MRI of the cervical, thoracic, and lumbar
spine is indicated to rule out intraspinal pathology.³,⁴

The amount of growth that remains in patients is
important in predicting curve progression and length of bracing, but is
also highly variable. Hoppenfeld, et al.⁵
has recently shown that capping of the iliac apophysis is not the final
indicator for the end of spinal growth. After capping of the iliac
apophysis (Risser 4) there was continued growth in overall height of
75% of patients, with a mean of 1.8 cm in girls and 2.5 cm in boys. No
growth occurred in patients after iliac apophysis fusion (Risser 5) or
closure of either the rib epiphysis or proximal humerus growth plates.

Keep your patients’ families out of trouble by warning
them that there is a lot of misinformation in places such as the
Internet. Some of these “secret” oral formulas have led to metabolic
imbalances requiring emergent hospitalization for the child. More
commonly, though, the only negative consequences of unproven therapies
are a monetary loss for the families (tens of thousands of dollars for
some) and delay of standard treatment.

This subject is a minefield of troubles. First off, be sensitive—this is a time of insecurity about one’s body for adolescents without
a disease. One way to stay out of trouble is to make certain you offer
bracing to patients, and document that you offered it. There have been
lawsuits taking the position that if bracing had been used, surgery
could have been prevented. When a patient’s curve warrants observation
or bracing, it is important to gain the family’s confidence that you
are “doing all that can be done,” but the curve may progress anyway.
Make certain the family understands that efficacy of a brace is quite
controversial, and usage in no way guarantees cessation or improvement
of curve. A reasonable approach is to say that, at best, the curve will
not progress, and that lasting improvement is highly unlikely. A
discussion of rebound effect⁶ (that
the curve will worsen after brace treatment is discontinued) best
occurs early in the course of brace treatment to prevent later feelings
of failure.

In general, bracing candidates have between 20 and 45
degrees of scoliosis, with growth remaining, and usually documented
progression of at least 5 degrees, though the last requirement may be
overlooked for immature patients with open triradiate cartilage or if a
strong family history is present. Take a radiograph in the brace to
evaluate correction, as a poorly-made brace might not be doing anything
of value.

It is important that physicians who prescribe braces
understand enough about bracing to make suggestions. In patients with
thoracic hypokyphosis or lordosis, bracing may worsen the sagittal
contour. Pads should be placed laterally, to eliminate any anterior
force on the spine. Lateral radiographs of such patients should be
taken in the brace to make certain the thoracic spine is not pushed
more anteriorly in the brace.

One of the most important ways a scoliosis surgeon can
stay out of trouble is a family conference in which the surgeon sets
expectations, completes an explicit and exhaustive consent process, and
shows models for optimum understanding. Complete correction of
deformity should never be guaranteed, and it is important to clarify
that the child’s back will never be completely normal. While it is our
experience, and that of others⁷ that
scoliosis surgery often relieves back pain, this outcome is
unpredictable and should never be an expectation. Families should
understand that a second operation is quite possible, and we suspect is
more likely than most surgeons admit to themselves.

Surgical indications for AIS are controversial, but are generally considered to include patients with:

There are exceptions for significant body deformity.

Surgical approach, method of instrumentation and
correction, and selection of levels to be fused are shrouded in
controversy and mysticism. We will attempt to share a few basic
principles and pitfalls.

The points below are subjects of much debate, but some recommendations to stay out of trouble are warranted.

For children with congenital scoliosis, keep out of
trouble by looking for associated abnormalities. The prevalence of an
intraspinal anomaly is approximately 40%. An MRI is warranted in a
child with congenital scoliosis who has signs or symptoms of a
neurologic problem, shows significant curve progression, or will be
undergoing surgery. Unlike children with infantile “idiopathic”
scoliosis, an MRI is not necessarily automatic as there is already a
known cause of the scoliosis—the congenital anomaly. Sixty one percent
of patients in one center had associated abnormalities affecting seven
systems. The most common abnormalities associated with vertebral
malformation were cranial nerve palsy, radial hypoplasia, club feet,
dislocated hip, Sprengel deformity, imperforate anus, and hemifacial
microsomia.²⁷ Renal anomalies (about
20%) may be evaluated with an ultrasound; cardiac anomalies (about 12%)
may be evaluated at the discretion of the primary care physician, who
may order an echocardiogram.

In general, documentation of curve progression over time should be noted before surgery is recommended, with three exceptions:

Traditional treatment for exceptions 1 and 2 is a
hemiepiphysiodesis, with the hope that improvement may occur with
growth. A posterior-only fusion has been

shown
to be relatively successful in preventing crankshaft in children with
congenital scoliosis, with only 15% of cases showing >10 degrees
progression of Cobb angle. However, children in two subsets did not
fare so well: children ≤4 years of age or with curves >50 degrees
had an incidence of crankshaft of 36% and 33%, respectively.²⁸

Many children with congenital scoliosis do not progress
significantly and never need spine surgery. However, once progression
is confirmed, surgery should be performed before a major deformity
results. Traditional teaching is that no spinal instrumentation is
needed and that most of the curve improvement comes from the position
of the spine in the cast. With modern pediatric spinal instrumentation
systems, or cervical systems in the very small children, significant
correction of curve can be achieved. In our experience, a posterior
fusion or anterior-posterior hemiepiphysiodesis in the young child with
congenital scoliosis frequently does not prevent significant rotational
deformity from progressing despite an apparently solid fusion with
little change in Cobb angle. Though encouraging, it is too early to
tell if pedicle screw fixation may help prevent this progression of the
rotational deformity. Parents should be warned that the “hump” may get
worse with growth.

In older children, spinal fusion and instrumentation can
often achieve significant curve correction and cosmetic improvement via
movement through adjacent open discs. Brace treatment is not effective
for congenital scoliosis.

CT scans are particularly helpful in defining anatomy
and anomalies, and useful for identifying otherwise unrecognized lamina
defects preoperatively. Stay out of trouble by exposing the spine
carefully as there are frequently unrecognized osseous defects in the
posterior elements, making an inadvertent plunge into the spinal canal
an all-too-real possibility. Exposure of a child’s spine with
congenital scoliosis is best not left to unsupervised surgeons in
training.

The first, and sometimes hardest, step is to recognize
that there is an infection. A small amount of drainage in the first few
days to weeks is unlikely to be an infection, though prophylactic oral
antibiotics may help prevent bacterial seeding through a draining
wound. Drainage, increasing pain, or progressive feelings of
generalized malaise months after surgery are highly suggestive of
infection. Do not be lulled into security
by a normal erythrocyte sedimentation rate (ESR) and c-reactive protein
(CRP) and lack of fever. This is common in long-standing spinal implant
infections.

If in doubt, an aspiration down to implants and/or
fusion may be performed in the office, but a negative result does not
rule out an infection. The best information is from operative
evaluation, and at times these cultures will remain negative. If the
fusion appears solid at time of surgery, consider taking out all
implants (see Dr. Lenke’s opinion). Ongoing research suggests that when
only a partial implant removal is performed; it is likely that another
surgery will be needed in the future to remove the rest of the implants
for persistent infection.³⁶

If the fusion is not yet solid, hardware should remain
in place. A single irrigation and debridement, with closure over
multiple drains (as one may clog) is usually adequate. Pay careful
attention to nutritional needs during this period. In problem cases a
wound VAC can be used as a last resort (Fig. 19-24).