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Chapter 25 Back Pain in Children and Adolescents 433
123. Willman CL, Busque L, Grith BB, et al. Langerhans’-cell
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124. Yeom JS, Lee CK, Shin HY, et al. Langerhans’ cell histiocytosis
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125. Garg S, Mehta S, Dormans JP. Langerhans cell histiocytosis of
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126. Plasschaert F, Craig C, Bell R, et al. Eosinophilic granuloma.
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127. Mammano S, Candiotto S, Balsano M. Cast and brace
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128. Raab P, Hohmann F, Kühl J, Krauspe R. Vertebral remodeling
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130. Kobayashi D, Satsuma S, Kamegaya M, et al. Musculoskeletal
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131. Santangelo JR, omson JD. Childhood leukemia presenting
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140. Grubb MR, Currier BL, Pritchard DJ, Ebersold MJ. Primary
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142. Lam CH, Nagib MG. Nonteratomatous tumors in the
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SECTION
IV
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SECTION
26
CHAPTER
Congenital scoliosis is a three-dimensional deformity of the
spine that is directly due to congenitally anomalous vertebral
development. is results in an imbalance of the longitudinal
growth of the spine, which is most typically progressive in
nature. By denition, this is dierent from neuromuscular
scoliosis, in which deformity is secondary to myoneural
causes, and idiopathic scoliosis, the cause of which is unknown.
Some cases of congenital scoliosis cause such minor deformity that they remain undetected; thus, the true incidence
in the general population remains dicult to determine.
However, current estimates suggest that approximately one in
1000 persons is aected.
e familial incidence in the congenital scoliosis population is estimated between 1% and 5%, suggesting that most
cases appear to be sporadic.
congenital scoliosis is 1 : 1.4.
To fully understand the management of congenital scoliosis,
one must rst appreciate the foundation of how the deformity
develops in utero. is discussion encompasses embryology
as it relates to the bony etiology of deformity and associated
dierences, a classication system that aids in understanding
growth potential, the natural history of curve progression,
assessment of the patient, various imaging modalities and
their unique utility, and, nally, treatment modalities.
Embryology
Congenital scoliosis is accurately described as altered embryologic development of the spine. Depending on which step of
development is altered, spine morphology will be dierently
impacted. e bony malformations that cause congenital scoliosis
typically occur during the fourth through sixth weeks of gestation. is timing is of particular importance, as it explains why
patients with congenital scoliosis oen have additional associated
anomalies, which likely develop during the same intrauterine
time period as other organ systems are similarly developing.
Normal Development
In the process of somitogenesis, paired paraxial mesoderms
on either side of the notochord condense to form somites.
1,2
3–6
e male/female ratio for
7–9
Congenital Scoliosis
Alexandra Miller Dunham
Paul D. Sponseller
Each somite further dierentiates into a ventral sclerotome
and a dorsolateral dermomyotome. During the fourth week of
gestation, cells from each sclerotome migrate ventrally to fully
engulf the notochord. e cranial half of one sclerotome and
the caudal half of the adjacent sclerotome fuse, each contributing a portion of cells to the development of a single vertebra.
us, a single vertebra results from the proper formation and
migration of cells from two somite levels (Fig. 26.1). e
ventrally migrated cells of the sclerotome will go on to form
the vertebral body, and the dorsal portion of the sclerotome
will form the vertebral arch as well as costal processes.
Ossication begins during the sixth week of gestation
from three primary ossication centers: one in the body (or
centrum, formed by early fusion of two centers) and one
in each half of the vertebral arch. During the sixth week of
development, mesenchymal cells between cranial and caudal
parts of the original sclerotome ll the space between two vertebral bodies to contribute to formation of the intervertebral
structures.
Somitogenesis relies on the oscillatory expression of
several genes and gene products, some of which have been
elucidated. Principal gene networks inuence Notch, Wnt, and
FGF pathway targets.
tive segmentation appear to be regulated by cell-autonomous
oscillations between permissive and nonpermissive states in a
consistently timed manner, so much so that somitogenesis is
said to be coordinated by a “clock-and-wave” mechanism
(Fig. 26.2). One of the many key outputs of the clock mecha-
nism is the interval production of MESP2 transcription factor,
which has been implicated in the formation of somite boundaries and the rostrocaudal development of the sclerotome.
11
12–15
e networks responsible for puta-
Associated Anomalies
Because the development of the spine coincides with the
development of many other organ systems, associated anomalies occur in 30% to 60% of children with congenital spine
malformations. Many associated anomalies are part of the
VATER association. e acronym includes various deciencies: vertebral defects (V), anal atresia (A), tracheoesophageal
stula (TE), radial limb reduction, and renal defects (R). e
acronym VATER was modied in 1975 to VACTERLS by
10
16,17
18,19
IV
435
436 PEDIATRICS
Somite
adding cardiac defect (C) and limb defect (L)
20–22
and single
umbilical artery (S; Fig. 26.3). e most common anomalies
involve the spinal cord, the genitourinary tract, and the cardiac
system. Intraspinal anomalies include problems such as tethered cord, diastematomyelia, syringomyelia/Chiari malformations, and intradural lipomas (present in up to 35% of patients
with congenital scoliosis). e most common genitourinary
defects are horseshoe kidney, renal aplasia, ectopic kidney,
duplication, reux, and hypospadias (present in up to 20% of
patients with congenital scoliosis). Congenital heart defects
range from the more common atrial and ventricular septal
defects to the more complex tetralogy of Fallot, transposition
T1
T2
Notochord
FIG. 26.1 Each vertebra is formed by a part of four somites.
T3
T4
Sclerotome
of the great vessels (present in up to 25% of patients with
congenital scoliosis).
23,24
Genetic Etiology
Mutations in downstream components and targets of the
Notch signaling pathway contribute to observed congenital
vertebral malformation phenotypes in humans,25 which are
mirrored in mouse models. Specically, genetic mapping has
enabled the identication of three forms of spondylocostal
dysostosis (SCD): mutations of DLL3
30–32
SCD2,
and LFNG to SCD3.
Alagille syndrome is an autosomal dominant condition
characterized by bile duct, heart, eye, kidney, pancreas, and
facial anomalies, as well as buttery vertebral anomalies.
Vertebral anomalies are observed in 22% to 87% of patients
with Alagille syndrome. Mutations in JAG1 have been identied in approximately 70% of patients with Alagille syndrome.35
Additionally, mutations in Notch2 have been observed, especially in those with severe renal anomalies.
Congenital vertebral anomalies are also found with a high
incidence in Klippel-Feil syndrome, which is characterized by
the combination of cervical fusion, limited neck range of
motion, short neck, and low hairline.37 Various genetic
anomalies have been reported to occur in association with
Klippel-Feil syndrome including SLIT3, FBXW11, DUSP1,
FGF18, DC-UbP, and CDCA2.
Additionally, congenital scoliosis has been associated with
Sprengel deformity, Mayer-Rokitansky-Küster-Hauser syndrome, Jarcho-Levin syndrome, Goldenhar syndrome, Genoa
syndrome,
39–42
and many others.
25,38
26–29
to SCD1, MESP2 to
36
33,34
FIG. 26.2 Illustration of “clock-and-wave” mechanism of somitogenesis segmentation. Oscillatory gene
expressions allow the development of “permissive peaks,” leading to somite formation. Shorter clock periods
lead to shorter somites and shorter intersomite spacing. PSM, presomitic mesoderm.
FIG. 26.3 Computed tomographic image of a 6-year-old child with
congenital scoliosis who also has epidural lipoma and neurenteric cyst at
T12.
Environmental Etiology
Growing evidence continues to suggest that congenital
scoliosis is not strictly a genetically caused anomaly. Studies
in mice suggest that maternal exposure to medications or
toxins, such as carbon monoxide, alcohol, boric acid, and/or
valproic acid, may cause congenital scoliosis.
43–48
Aberrations
in the developmental milieu have also been associated with
vertebral malformations consistent with congenital scoliosis
such as hyperglycemia, hypoxia, and hyperthermia.
45,49–51
e
causative mechanism underlying the carbon monoxide eect
on vertebral anomalies remains vague. However, maternal
acute exposure to carbon monoxide during embryo somitogenesis may act via gene mutation from the resulting hypoxia
or directly by disruption of the cartilaginous spine.
e interplay between genetics and environmental factors is
complex. Epigenetic factors in the development of congenital
vertebral malformations are a possible pursuit.52 e observation that increased DNA methylation can alter the phenotypic
expression of tail kinks in the axin-fused mouse (AxinFu)
supports an epigenetic contribution to congenital scoliosis.
43,53
e literature continues to grow in elucidating the multiple
factors of pathogenesis of congenital vertebral malformations.
Classication
Chapter 26 Congenital Scoliosis 437
FIG. 26.4 Wedge vertebrae due to a mild form of unilateral vertebral failure
of formation. Vertebral height is asymmetrical on the right and left sides.
As in other types of scoliosis, compensatory curves also
develop.
Failures of Formation
Failures of formation (type I deformity) exist along a broad
spectrum and have multiple subtypes characterized by longitudinal growth potential. Formation deformity can be partial,
which causes wedged vertebrae with intact pedicles, or complete, which causes hemivertebrae with a unilateral pedicle
(Fig. 26.4). Vertebral growth typically is provided by apophyses
on both the superior and inferior endplate of each vertebra.
In vertebrae aected by failure of formation, the apophyses
may be disrupted, thus aecting growth and lending a natural
method to the subtyping of type I deformity.
Fully segmented: Both the superior and inferior endplates
•
of the aected vertebrae have growth potential, with disc
space both above and below. Adjacent vertebrae are normal.
Semisegmented: Either the superior or inferior endplate of
•
the aected vertebrae has growth potential, with normal
disc space with the adjacent vertebrae; the other end is
fused to the adjacent vertebrae with an intervening thin,
brous lamellar tissue (Fig. 26.5).
Nonsegmented: Neither the superior nor inferior endplate
•
of the aected vertebrae has growth potential. Both endplates are fused to the adjacent vertebrae and the interval
disc space is replaced by brous lamellar tissue (see
Fig. 26.5).
Incarcerated: Both the superior and inferior endplates of
•
the aected vertebrae have growth potential; however, the
aected vertebra is bound within the lateral margins of the
adjacent vertebrae, and the adjacent vertebrae compensate
for the deformity by expanding their growth potential. is
results in the aected vertebrae appearing “carved into” the
adjacent levels (see Fig. 26.5).
SECTION
IV
Two basic types of vertebral anomalies occur: failures of
formation and failures of segmentation.
54-57
ese anomalies
can occur as a solitary malformation or in conjunction with
additional vertebral malformations, adding complexity to
the resulting deformity with each additional malformation.
Failures of Segmentation
Failure of segmentation (type II deformity) is associated with
derangements of the segmentation phase of somitogenesis.
Improper segmentation occurs along a spectrum from a
partial failure resulting in a partially segmented vertebra,
438 PEDIATRICS
AB CD
FIG. 26.5 Hemivertebrae, classied according to growth potential. (A) Segmented hemivertebra. (B)
Semisegmented hemivertebra. (C) Incarcerated hemivertebra. (D) Nonsegmented hemivertebra.
FIG. 26.6 Congenital unilateral bar. Partial fusion between two vertebrae
prevents longitudinal growth on its side.
causing a bar, or complete failure resulting in a complete
absence of intervening space between vertebrae, causing a
block vertebra. A congenital bar can be anterior, posterior,
lateral, or mixed. Depending on the position of the bar, a
dierent deformity may develop as the patient grows (Fig.
26.6). As with other bar malformations in the body, the bony
vertebral bar resulting from a partial failure in segmentation
will restrict growth in the same plane of direction as the bar.
Mixed Deformity
Vertebral anomalies oen exist in conjunction—failures of
formation and failures of segmentation frequently coexist as
mixed deformity (type III deformity). Occasionally, anomalies
are found on several levels. For example, unilateral bar with
contralateral fully segmented hemivertebra is a type III deformity and has the most rapid progression of curvature among
the deformities (Fig. 26.7).
Natural History
Congenital scoliosis, as with other types of scoliosis, progresses
in the majority of patients during periods of rapid growth.
Given that deformities of congenital scoliosis are by denition
present at birth, they are subject to the intense growth of early
FIG. 26.7 Radiograph of 9-year-old child with congenital scoliosis of mixed
pattern, including multiple hemivertebrae, both incarcerated and
nonincarcerated, and fused pedicles and ribs on the left at T9–T10.
childhood—progression is most rapid in the rst 3 years of
life. Multiple reviews have shown that, statistically, 25% of
curves do not progress, 25% progress minimally, while 50%
progress signicantly and require treatment
58–61
(Fig. 26.8).
Without any treatment, 85% of patients with congenital scoliosis will have a curve greater than 45 degrees by maturity.56 e
potential for the increase in curvature is dependent on the
imbalances of growth potential (Fig. 26.9). e natural history
of congenital scoliosis relates to the type of deformity, location, number and span of deformities, initial severity of the
scoliosis, and the global growth potential balance between
each side of the spine. Analysis of these factors will allow the
Chapter 26 Congenital Scoliosis 439
apophyses
apophyses
A
FIG. 26.8 Radiographs of congenital scoliosis with VACTERLS association
(vertebral defects, anal atresia, cardiac defects, tracheoesophageal stula,
renal anomalies, and limb abnormalities) managed by observation since
birth. Right thoracic curve and compensatory lumbar curve remain relatively
unchanged from birth at (A) age 1 year and (B) age 8 years.
B
surgeon to determine the most appropriate treatment at the
proper time.
Location
e most deforming anomalies tend to be those at the cervicothoracic or lumbosacral junction. Both types of deformity
(formation and segmentation) may be lateral, causing scoliosis;
dorsal, causing lordosis; ventral, causing kyphosis62; or a
combination of these positions. Posterolateral positioning of
a hemivertebra may cause kyphoscoliosis; anterolateral may
cause kyphoscoliosis.62 Furthermore, if the anterior part of the
vertebra is decient while the dorsal part is not malformed,
kyphoscoliosis, especially in the lumbar spine, is common.
58,62
Progression of Curvature by Deformity Type and Location
e spectrum of vertebral deformities associated with congenital scoliosis is associated with dierent growth potentials.
In general, curves with fully segmented hemivertebrae have a
greater capacity for continued growth potential and therefore
greater risk for progression of curvature, whereas vertebrae
whose apophysis is blocked are at minimal risk. Complex
combinations of deformity contribute to a more pronounced
spine imbalance and are associated with the greatest risk for
curve progression.
For example, complete block vertebrae (complete type
II deformity) or nonsegmented hemivertebrae are blocked
SECTION
IV
1 growth
2 growth
FIG. 26.9 Hemivertebra forcing spine into a curve. There are two growth apophyses on the hemivertebra side
and only one on the other side, leading toward worsening during growth.
440 PEDIATRICS
on both the superior and inferior apophysis. erefore, the
longitudinal growth potential is very small, and tends not to
cause progressive scoliosis. Block vertebrae usually occur in
multiple sites along the spine and are associated with a small
potential for growth and a slow rate of progression (<1 degree
per year
56,58,63
). Nonsegmented hemivertebrae demonstrate a
similar rate of progression since they are also limited in their
growth potential by being fused to the adjacent vertebrae.
Incarcerated hemivertebrae also do not cause progressive scoliosis. When wedge vertebrae are located in the lower thoracic
or thoracolumbar regions, the deformity demonstrates a relatively low rate of progression of 1 to 2 degrees per year.
56,58,63
e location and number of hemivertebrae deformities
along the spine aect the rate of curve progression. Speci-
cally, the upper thoracic hemivertebrae tend to progress on
average 1 to 2 degrees per year before puberty, then 2 to 2.5
degrees during the pubertal growth spurt. However, when the
deformity is present in the lower thoracic spine, curves demonstrate a more rapid progression of 2 degrees per year before
puberty and 2.5 to 3 degrees per year during the pubertal
growth spurt. Furthermore, when located in the thoracolumbar spine, the rate of progression is again much more rapid—2
to 2.5 degrees per year before puberty and about 3.5 degrees
per year during puberty. e more rapid progression and
caudal location result in substantial trunk imbalance compared to other locations of curvature.
56,58,63
Similarly, the span and location along the spine of a unilat-
eral unsegmented bar greatly aect the natural development of
the resultant curve. When located in the upper thoracic spine,
the rate of progression averages 2 degrees per year before
puberty and 4 degrees aerward. For deformity located within
the lower thoracic area, curvature progression is 5 degrees per
year before puberty and 6.5 degrees per year during puberty.
Again, deformities with an apex located in the thoracolumbar
area demonstrate the highest rate of deterioration—curves
typically increase 6 degrees per year prior to puberty and 9
degrees per year aer. Curves in the lumbar area progress
about 5 degrees per year both before and aer puberty.
56,58,63
e most progressive anomaly is a convex, fully segmented
hemivertebra associated with a concave unilateral bar. ere
is no growth potential on the side of the bar, but the side of
the spine with the segmented hemivertebra continues to grow.
erefore, the spine is imbalanced, resulting in highly progressive curves. ese types of disorders occur more frequently
in the thoracic spine and are the most severe of all scoliosis
disorders. ey demonstrate rapid deterioration of up to 14
degrees per year prior to puberty, resulting in trunk shortening,
limb-length discrepancy, and frank cosmetic deformity.
56,58,63
patient grows, the patient’s thorax becomes unable to support
normal respiration, a condition termed thoracic insuciency
syndrome (TIS). TIS can be assessed both clinically by respiratory rate and the thumb excursion test, by specic tests such
as pulmonary function tests, and radiographically by plain
radiographs and computed tomography (CT) volumetric
studies.67 Early fusion of scoliotic deformity before age 9 years,
especially in patients requiring more than four levels of fusion
and those with proximal fusions, also puts patients at risk for
the development of restrictive pulmonary disease.
68,69
Additionally, compared with healthy peers, congenital scoliosis
patients who were treated with extensive early spinal fusion
demonstrate decreased pulmonary function test values in
forced vital capacity, forced expiratory volume, vital capacity,
and total lung capacity, and lower quality-of-life scores at 6.9
years’ follow-up. Compared to congenital scoliosis patients
who were fused in nonthoracic areas, patients treated with
thoracic spinal fusion have reported shorter spinal height,
more pain, and lower pulmonary functioning.70 e increased
appreciation of the need to preserve pulmonary function and
to allow maximum spinal height has spurred the development
of growth-preserving surgical alternatives to spinal fusion,
including growing rods, guided growth, epiphysiodesis, and
Assessment of Patient
Physical Examination
e physical examination of a patient with congenital scoliosis
is guided by the knowledge of a high frequency of other structural and neural anomalies. Maternal, perinatal history, and
developmental milestones must be fully explored. Presence
of a dimple, nevi, hemangiomas, or hairy patches and/or any
other cutaneous mark on the back should be noted. e sagittal plane balance and coronal balance, shoulder malalignment,
as well as any deviation of head and trunk from the center
of the pelvis should be checked. Due to the connection of
scoliosis with Klippel-Feil syndrome, the cervical spine should
be especially examined, including range of neck motion. In
addition, it is critical to assess and document the neurologic
status, including strength, reexes, presence of atrophy, and
the existence of latent ataxia or myelopathy. Flexibility of the
deformity, gait, trunk shortening, and limb-length inequality
should be checked. Pain, if present, should be localized and
quantied. e examiner should search for other anomalies of
the extremities (particularly radial malformation).
Eects on Thoracic Contents
Congenital defects in the ribs and vertebrae oen occur in
conjunction. Rib fusion in the setting of scoliosis may constrict
the thoracic contents during a crucial developmental period,
and ultimately compromise pulmonary development. is
occurs because alveolar development mostly takes place before
5 years of age and early restriction of the respiratory physiology eectively causes restrictive lung disease.
64–66
As the
Associated Anomalies
Patients with congenital scoliosis have an increased incidence
of other systemic dierences including but not limited to
respiratory, cardiac, renal, gastrointestinal, and neurologic
systems. Pulmonary function tests, echocardiogram, and renal
duplex may add to the overall case preparation. Oen, the
renal system is visualized on spinal magnetic resonance
imaging (MRI), obviating the need for an additional study.71
Collaboration with other specialties and with the patient’s
Chapter 26 Congenital Scoliosis 441
SECTION
IV
AB C
FIG. 26.10 It is easier to analyze a (A) segmented hemivertebra or a (B) unilateral bar when radiographs are
taken prior to 4 years of age. (C) Lumbar segmented hemivertebra in a 9-year-old child.
primary care provider will serve to prepare the surgical team
and optimize the patient for surgery.
Imaging
Preoperative CT scans dene the anatomy and posterior
element deciencies. MRIs can exclude associated conditions
of the spine, craniocervical junction, and viscera.
Radiographs
Plain radiographs remain the standard for the diagnosis and
classication of congenital scoliosis and measuring curve
magnitude and progression. Ideally, radiographs are obtained
prior to 4 years of age (Fig. 26.10). Aer this time period, it
may be dicult to fully appreciate the deformity because
vertebrae are more ossied, especially in the areas of fusion or
bars. Radiographs that were taken earlier—such as chest,
abdominal, or renal radiographs—can provide valuable information to the orthopaedic surgeon about early development.
Subtle ndings—such as the presence and spacing of pedicles
as well as fused, atretic, or absent ribs—provide clues about
underlying deformity.
Standard anteroposterior and lateral lms allow one to
check the type and the location of deciency, to measure the
spine curvature, and to assess the pedicle width. However,
studies have shown that, even in the hands of an expert,
congenital scoliosis curves measured by the Cobb angle on traditional radiographs are dicult to reliably measure. Irregular
landmarks and irregular numbering/positioning of vertebrae
increase intraobserver and interobserver measurement error
up to 10 degrees. Comparing current radiographs with prior
radiographs reduces this error.
involve normally formed vertebrae, they are more reproducibly measured and can serve as a marker for progression of
the congenital curvature. If a compensatory curve has not
progressed, it is less likely that signicant progression has
occurred in a congenital curve.
Computed Tomography
Intraobserver reliability of measuring Cobb angles from
plain radiographs is low in congenital scoliosis, with up to
10 degrees of measurement error; interobserver reliability
demonstrates a greater measurement error.74 Accurate and
reliable reporting of curves as the patient matures through
time is especially dicult. Furthermore, plain radiographs
cannot demonstrate the spatial relationship of each structure
of the vertebrae and the three-dimensional component of
congenital scoliosis is dicult to appreciate. CT with threedimensional reconstruction can be used to more completely
and more consistently identify spinal abnormalities, especially
posterior element deciencies, in complex cases (Fig. 26.11).
Spatial disposition of the aected vertebrae and the balance of
deformity can be better classied. CT and three-dimensional
reconstruction aid in the evaluation of the thorax and the
lung and highlight thoracic wall deformities, including: rib
synostoses, rib hypoplasia or agenesis, intracanal protrusions
through the radicular foramina, and evaluation of TIS.
72–74
Since compensatory curves
75,76
442 PEDIATRICS
FIG. 26.11 Computed tomographic image with three-dimensional
reconstruction allows the surgeon to more fully appreciate complex spine
abnormalities.
Magnetic Resonance Imaging
Intraspinal anomalies are oen associated with congenital
scoliosis. Careful physical examination can suggest underlying
spinal dysraphism.
lies in 30% to 41% of cases.
38,77
MRI demonstrates intraspinal anoma-
78–80
Congenital scoliosis patients
with cervical and thoracic hemivertebrae tend to have more
intraspinal abnormalities than those with lumbar hemivertebrae.81 e most common anomalies reported are tethered
cord, syringomyelia, and diastematomyelia. MRI is indicated
to assess congenital scoliosis because of three factors:
1. Intraspinal anomalies are encountered in about one-third
of cases of congenital scoliosis.81 Some may require neurosurgical treatment for their own sake (e.g., a large syrinx),
whereas others may require neurosurgical collaboration if
corrective orthopaedic surgery is planned (e.g., diastematomyelia).
2. Normal neurologic exam does not rule out malformations
of the neuraxis.
79,80
3. MRI of the spine will also typically demonstrate the pres-
ence or absence of renal anomalies, which may or may not
capture evaluation of genitourinary anomalies.
71
In practice, given the need for general anesthesia to obtain
MRI in young children, it should be ordered when there is
a concerning examination nding and/or prior to surgical
procedure.
Treatment
ose malformations that present a very low progression rate
should be periodically evaluated for possible progression.
However, about 50% of congenital scoliosis cases require
surgical treatment.
58–61
Correction of deformity should occur
early in congenital scoliosis, which allows the correction of the
fewest vertebrae possible and protection against continued,
severe structural spine decompensation.
82–84
Congenital vertebral anomalies require close clinical monitoring at periodic intervals during growth. Consistent observation allows for assessment of the evolution of spinal curves.
In complex malformations, early treatment is oen more
straightforward and safer.
Nonoperative
Contrary to idiopathic scoliosis, nonoperative treatment has
little value in congenital scoliosis. Only a small number of
cases, characterized by long and exible curves, may be tem-
porized by bracing to slow the progression of the curva-
58,85,86
tures.
However, t hese curves will eventually decompensate
to the degree requiring surgical management. In general,
carefully monitoring every 4 to 6 months with regular examination and radiographic evaluation is prudent in curves
measuring up to 40 degrees.87 However, other factors—
including deformity personality, pulmonary, cardiac, or neurologic function—may require earlier surgical intervention.
For example, spines with successive, fully segmented hemivertebrae concomitant with additional severe deformities of the
rib cage, therefore causing TIS, may undergo surgical intervention earlier regardless of the Cobb’s angle.
87
Operative
Without any treatment, 85% of patients with congenital
scoliosis will have a curve greater than 45 degrees by maturity.56 Congenital scoliosis progresses because the growth
potential of the spine is imbalanced. Early recognition of
curves with a poor prognosis is crucial to prevent severe
curve progression and possible neurologic complications. e
advent of pediatric-specic implants has minimized the
problem of implant prominence in young children and has
been shown to be safe from a neurologic standpoint.83 Motorand sensory-evoked potential monitoring is recommended
whenever possible. ere is an increased risk of a perioperative neurologic injury when baseline monitoring cannot be
established.88 Furthermore, postoperative monitoring and
thorough documentation of neurologic functioning is important because paraplegia aer deformity surgery may present
in a delayed fashion, especially in the rst 72 hours.
Indications for surgery depend on many factors, including
the nature of the vertebral anomaly as well as its location and
span, the curve magnitude and its exibility, the patient’s age,
and the presence of other deformities. e aim of surgery is
fourfold: (1) achieve a straight spine, with or without deformity
reduction; (2) restore a physiologic sagittal prole while maintaining exibility; (3) limit curve progression; and (4) preserve
normal spinal growth as much as possible by fusing only a
short segment. Seven major operations have been described:
posterior spine fusion, combined anterior and posterior spine
fusion, convex hemiepiphyseodesis, hemivertebra excision,
89,90