Scoliosis is the abnormal curvature of
the spine. It affects about 2 - 3% of the population (about 6
million people in the United States). It can occur in adults,
but is more commonly diagnosed for the first time in children
aged 10 - 15 years.
Scoliosis most commonly
develops in the area between the upper back (the
thoracic area) and lower back (lumbar area). It
may also occur only in the upper or lower back. The doctor
attempts to define scoliosis by the following
- The shape of the curve
- Its location
- Its direction
- Its magnitude
- Its causes, if possible
The treatments for scoliosis are not always
straightforward. Some young people only need careful
observation. When treatment is necessary, several options,
including braces and various surgical procedures, can
The first gene clearly related to idiopathic
scoliosis was found in a study published in 2007. Variations
in this gene, CHD7, can make people more susceptible to
Bioactive glass seems to be as effective as
bone grafts in idiopathic scoliosis patients undergoing
fusion surgery. There were fewer complications with the
bioactive glass procedures.
New Treatment Approach:
A new device, the vertical expandable
prosthetic titanium rib (VEPTR), is showing promise in the
treatment of severe congenital scoliosis with chest
deformities. The device, which is implanted through surgery,
can be adjusted as the child grows.
Vertebrae. The spine is a column of small
bones, or vertebrae, that support the entire upper
body. The column is grouped into three sections of
vertebrae are the 7 spinal bones that support the
vertebrae are the 12 spinal bones that connect to the
vertebrae are the 5 lowest and largest bones of the
spinal column. Most of the body's weight and stress falls on
the lumbar vertebrae.
Each vertebra can be designated by using a
letter and number; the letter reflects the region (C=cervical,
T=thoracic, and L=lumbar), and the number signifies its
location within that region. For example, C4 is the fourth
bone down in the cervical region, and T8 is the eighth
Below the lumbar region is the sacrum, a
shield-shaped bony structure that connects with the pelvis at
the sacroiliac joints. At the end of the sacrum are 2 - 4
tiny, partially fused vertebrae known as the coccyx or
The Spinal Column
and its Curves. Altogether, the vertebrae form the spinal
column. In the upper trunk the column normally has a gentle
outward curve (kyphosis) while the lower back has a
reverse inward curve (lordosis).
The Disks. Vertebrae in the spinal column
are separated from each other by small cushions of cartilage
known as intervertebral disks. Inside each disk is a
jelly-like substance called the nucleus pulposus, which
is surrounded by a tough, fibrous ring called the annulus
fibrosis. The disk is 80% water. This structure makes the
disk both elastic and strong. The disks have no blood supply
of their own, relying instead on nearby blood vessels to keep
Processes. Each vertebra in the spine has
a number of bony projections, known as processes. The
spinous and transverse processes attach to the muscles in the
back and act like little levers, allowing the spine to twist
or bend. The particular processes form the joints between the
vertebrae themselves, meeting together and interlocking at the
zygapophysial joints (more commonly known as facet or
Spinal Canal. Each vertebra and its
processes surround and protect an arch-shaped central opening.
These arches, aligned to run down the spine, form the spinal
canal, which encloses the spinal cord, the central
trunk of nerves that connects the brain with the rest of the
Scoliosis is the abnormal curving of the spine.
While the normal spine has gentle natural curves that round
the shoulders and make the lower back curve inward, scoliosis
typically causes deformities of the spinal column and rib
cage. In scoliosis, the spine curves from side-to-side to
varying degrees, and some of the spinal bones may rotate
slightly, making the hips or shoulders appear uneven. It may
develop in the following way:
As a single primary side-to-side curve
(resembling the letter C), or
As two curves (a primary curve along with a
compensating secondary curve that forms an S
Scoliosis most commonly develops in the area
between the upper back (the thoracic area) and lower
back (lumbar area). It may also occur only in the upper
or lower back. The doctor attempts to define scoliosis by the
The shape of the curve
Its causes, if possible
The severity of scoliosis is determined by the
extent of the spinal curve and the angle of the trunk rotation
(ATR). It is usually measured in degrees. Curves of less than
20 degrees are considered mild and account for 80% of
scoliosis cases. Curves that progress beyond 20 degrees need
medical attention. Such attention, however, usually involves
periodic monitoring to make sure the condition is not becoming
Scoliosis affects about 2 - 3% of the population
(about 6 million people in the United States). It can occur in
adults but is more commonly diagnosed for the first time in
children aged 10 - 15 years. About 10% of adolescents have
some degree of scoliosis, but less than 1% of them develop
scoliosis that requires treatment. The condition also tends to
run in families. Among persons with relatives who have
scoliosis, about 20% develop the condition.
Among adults, previous reports have indicated a
prevalence of scoliosis of up to 32%. However, a recent study
of 75 healthy adults aged 60 years and older, with no known
history of scoliosis or prior spine surgery, suggested a rate
of 68%. Scoliosis was not linked to physical or social
impairment in this population.
Defining Scoliosis by the Shape of the
Scoliosis is often categorized by the shape of
the curve, usually as either structural or
Structural scoliosis: In addition to the
spine curving from side to side, the vertebrae rotate,
twisting the spine. As it twists, one side of the rib cage
is pushed outward so that the spaces between the ribs widen
and the shoulder blade protrudes (producing a rib-cage
deformity, or hump). The other half of the rib cage is
twisted inward, compressing the ribs.
Nonstructural scoliosis: The curve does not
twist but is a simple side-to-side curve.
Other abnormalities of the spine that may occur
alone or in combination with scoliosis include
hyperkyphosis (an abnormal exaggeration in the backward
rounding of the upper spine) and hyperlordosis (an
exaggerated forward curving of the lower spine, also called
Defining Scoliosis by Its Location
The location of a structural curve is defined by
the location of the apical vertebra. This is the bone
at the highest point (the apex) in the spinal hump.
This particular vertebra also undergoes the most severe
rotation during the disease process.
Defining Scoliosis by Its Direction
The direction of the curve in structural
scoliosis is determined by whether the convex (rounded)
side of the curve bends to the right or left. For example, a
doctor will diagnose a patient as having right thoracic
scoliosis if the apical vertebra is in the thoracic (upper
back) region of the spine, and the curve bends to the
Defining Scoliosis by Its Magnitude
The magnitude of the curve is determined by
taking measurements of the length and angle of the curve on an
Until recently, researchers have not been able
to identify any specific genetic abnormalities that make a
young person susceptible to spinal distortion. The first gene
clearly related to idiopathic scoliosis was found at the
conclusion of a 10-year study, the results of which were
published in 2007. Variations in this gene, CHD7, can make
people more susceptible to idiopathic scoliosis. It is still
unclear how this gene affects a person's susceptibility.
Physical Abnormalities. Researchers are
investigating possible physical abnormalities that may cause
imbalances in bones or muscles that would lead to scoliosis.
Among them are the following:
Imbalances in muscles around the vertebrae.
Some research suggests that imbalances in the muscles around
the vertebrae may make children susceptible to spinal
distortions as they grow.
High Arches. One study showed a higher
incidence of abnormally high arches in the feet of people
with idiopathic scoliosis, suggesting that altered balance
may be a factor in certain cases.
Problems in Coordination. Some experts
are looking at inherited defects in perception or coordination
that may cause unusual growth in the spine of some children
Other Biological Factors. Several other
biological factors are being investigated for some
contribution to scoliosis:
Abnormalities in collagen, the critical
structural protein found in muscles and bones. Enzymes known
as matrix metalloproteinases are involved in the
repair and remodeling of collagen. Researchers have found
high levels of the enzymes in the disks of patients with
scoliosis, suggesting that the enzymes may contribute to
curve progression. Elevated levels of the enzymes can cause
abnormalities in components in the spinal disks,
contributing to disk degeneration.
A possible defective gene responsible for
production of fibrillin, an important component of
connective tissue that makes up bones and muscles.
Abnormalities in a protein called
platelet calmodulin that binds to calcium. This
protein acts like a tiny muscle and pulls clots together.
Measuring levels of this protein may eventually help predict
whether scoliosis will worsen.
In 80% of patients, the cause of scoliosis is
unknown. Such cases are called idiopathic scoliosis.
(Idiopathic means without a known cause.) Idiopathic scoliosis
may be due to multiple, poorly understood inherited factors,
most likely from the mother's side. However, the severity
often varies widely among family members who have the
condition, suggesting that other factors must be present.
Idiopathic scoliosis may be classified based on
age of presentation. Age of onset may also determine the
treatment approach. The classification is as follows:
Infantile: Up to 3 years old
Juvenile: Four to 9 years old
Adolescent: Ten years old through the teen
Idiopathic scoliosis may be initially diagnosed
in adults during evaluation for other back complaints or
disorders, although the curve is unlikely to be
Congenital scoliosis is caused by inborn spinal
deformities that may result in absent or fused vertebrae.
Kidney problems, particularly having only one kidney, often
coincide with congenital scoliosis. The condition usually
becomes evident at either age 2 or in children ages 8 - 13 as
the spine begins to grow more quickly, putting additional
stress on the abnormal vertebrae. It is essential to diagnose
and monitor such curvatures as early as possible, since they
can progress quickly. Early surgical treatment -- before age 5
-- may be important in many of these patients to prevent
Neuromuscular scoliosis may result from a
variety of causes, including:
These patients frequently have significant
complications, including an increased risk for skin ulcers,
lung problems, and significant pain.
Causes of Degenerative Lumbar Scoliosis in
Adult scoliosis has two primary causes:
Progression of childhood scoliosis.
Degenerative lumbar scoliosis. Degenerative
lumbar scoliosis is a condition that typically develops
after age 50. With this condition, the lower spine is
affected, usually due to disk degeneration. Osteoporosis, a
serious problem in many older adults, is not a risk factor
for new-onset scoliosis, but it can be a contributing
factor. In most cases, however, it is not known why
scoliosis occurs in adults.
Conditions That Affect the Spinal Column and
Scoliosis may be a result of various conditions
that affect bones and muscles associated with the spinal
column. They include the following:
Tumors, growths, or other small
abnormalities on the spinal column. For example,
syringomyelia, a disorder in which cysts form along the
spine, can cause scoliosis. These spinal abnormalities may
play a larger role in causing some cases of scoliosis than
Stress fractures and hormonal abnormalities
that affect bone growth in young, competitive athletes.
Turner syndrome, a genetic disease in
females that affects physical and reproductive development.
Other diseases that can cause scoliosis are
Marfan syndrome, Aicardi syndrome, Friedreich ataxia,
Albers-Schonberg disease, rheumatoid arthritis, Cushing
syndrome, and osteogenesis imperfecta.
Causes of Nonstructural Scoliosis
Nonstructural scoliosis is usually not a serious
problem, since the curve is side to side. It can develop from
a number of physical problems, including the following:
Unequal leg length. Injury, a shortened
Achilles tendon, or other structural inborn problems can
cause this very common condition. Unequal leg length rarely
causes any problems and usually needs no treatment other
than a lift in one of the shoes to equalize the length.
Risk Factors for Initial Scoliosis.
Idiopathic scoliosis, the most common form, occurs most often
during the growth spurt right before and during adolescence.
(Between 12 - 21% of idiopathic cases occur in children ages 3
- 10 years, and less than 1% in infants.) Mild curvature
(under 20 degrees) occurs about equally in girls and boys, but
curve progression is 10 times more likely to occur in girls.
Being taller than average at earlier ages may put some girls
at risk, but other factors must be present to produce
scoliosis. A risk factor that affects females is delayed onset
of menstruation, which can prolong the growth spurt period,
thus increasing the possibility for the development of
Risk Factors for Curvature Progression.
Once scoliosis is diagnosed, it is very difficult to predict
who is at highest risk for curve progression. About 2 - 4% of
all adolescents develop curvature of 10 degrees or more, but
only about 0.3 - 0.5% of teenagers have curves greater than 20
degrees, which requires some medical attention.
Medical Risk Factors
People with certain medical conditions that
affect the joints and muscles are at higher risk for
scoliosis. These conditions include rheumatoid arthritis,
muscular dystrophy, polio, and cerebral palsy. Children who
receive organ transplants (kidney, liver, and heart) are also
at increased risk.
Scoliosis may be evident in young athletes, with
a prevalence of 2 - 24%. The highest rates are observed among
dancers, gymnasts, and swimmers. The scoliosis may have been
due in part to loosening of the joints, delay in puberty onset
(which can lead to weakened bones), and stresses on the
growing spine. There have also been other isolated reports of
a higher risk for scoliosis in young athletes who engage
vigorously in sports that put an uneven load on the spine.
These include figure skating, dance, tennis, skiing, and
javelin throwing, among other sports. In most cases, the
scoliosis is minor, and everyday sports do not lead to
scoliosis. Exercise has many benefits for people both young
and old and may even help patients with scoliosis.
In general, the severity of the scoliosis
depends on the degree of the curvature and whether it
threatens vital organs, specifically the lungs and heart.
Mild Scoliosis (less than 20
degrees). Mild scoliosis is not serious and requires no
treatment other than monitoring.
Moderate Scoliosis (between 25 and 70
degrees). It is still not clear whether untreated
moderate scoliosis causes significant health problems later
on. Some studies have found no difference in either back
pain or survival rates in adult untreated patients versus
the general population. In one study, adults with moderate
scoliosis had normal lung function, although they had
difficulty exercising. (This low exercise tolerance might
have been because many patients with scoliosis do not engage
in regular physical activity.)
Severe Scoliosis (over 70 degrees).
If the curvature exceeds 70 degrees, the severe twisting of
the spine that occurs in structural scoliosis can cause the
ribs to press against the lungs, restrict breathing, and
reduce oxygen levels. The distortions may also cause
dangerous changes in the heart.
Very Severe Scoliosis (Over 100
degrees). Eventually, if the curve reaches over 100
degrees, both the lungs and heart can be injured. Patients
with this degree of severity are susceptible to lung
infections and pneumonia. Curves greater than 100 degrees
increase mortality rates, but this problem is very uncommon
Some experts argue that simply measuring the
degree of the curve may not identify patients in the moderate
and severe groups who are at greatest risk for lung problems.
Other factors (spinal flexibility, the extent of asymmetry
between the ribs and the vertebrae) may be more important in
predicting severity in this group.
Effects on Bones
Scoliosis is associated with osteopenia, a
condition characterized by loss of bone mass. Many adolescent
girls who have scoliosis also have osteopenia. Some experts
recommend measuring bone mineral density when a patient is
diagnosed with scoliosis. The amount of bone loss may help
predict how severely the spine will curve. Preventing and
treating osteopenia may help limit further curve
If not treated, osteopenia can later develop
into osteoporosis. Osteoporosis is a more serious loss of bone
density that is common among postmenopausal women. Adolescents
who have scoliosis are at increased risk of developing
osteoporosis later in life. [See In-Depth Report#18:
Spine Problems in Previously Treated Scoliosis
After 20 years or more, scoliosis patients who
were previously treated with surgery experience small but
significant physical impairments, (mainly mild back problems),
compared to their peers without scoliosis. More people with a
history of scoliosis report having to take days off from work,
compared to people who never had the condition. In one study,
only 1.5% of the scoliosis group had severe debilitating back
pain. In general, most patients experienced a similar quality
of life to peers who never had the condition.
The following are some possible causes of later
back problems in people with a history of treated
Spinal fusion disease. Patients who
are surgically treated with fusion techniques lose
flexibility and may experience weakness in back muscles due
to injuries during surgery.
Disk degeneration and low back
pain. With disk degeneration, the disks between the
vertebrae may become weakened and rupture. In some patients,
particularly those treated with the first generation of the
Harrington rods, years after the original surgeries the
weight of the instrumentation can cause disk and joint
degeneration severe enough to require surgery. Treatment may
involve removal of the old rods and extension of the fusion
into the lower back. Still, most patients do not experience
significant back pain from these problems.
Height loss. Fusion of the spine
may inhibit growth somewhat. However, much of the growth
takes place in long bones, which are not affected.
Lumbar flatback. This condition is
most often the result of a scoliosis surgical procedure
called the Harrington technique, which eliminated lordosis
(the inward curve in the lower back). Adult patients with
flatback syndrome tend to stoop forward. They may experience
fatigue and back and even neck pain.
Rotational trunk shift (uneven
shoulders and hips).
Evidence suggests that previous treatment with
braces may also cause mild back pain and more days off, but
problems appear to be less than with surgery. In one study,
dysfunction was comparable to people without a history of
Problems in Adult-Onset or Untreated Childhood
Pain in adult-onset or untreated childhood
scoliosis often develops because of posture problems that
cause uneven stresses on the back, hips, shoulders, necks, and
legs. In one study conducted 20 years after growth had
stopped, two-thirds of adults who had lived with curvatures of
20 - 55 degrees reported they experienced back pain. Other
studies have reported that adults with a history of scoliosis
tend to have chronic back pain, and more back pain than the
Nearly all individuals with untreated scoliosis
will develop spondylosis, an arthritic condition in
the spine. The joints become inflamed, the cartilage that
cushions the disks may thin, and bone spurs may develop. If
the disk degenerates or the curvature progresses to the point
that the spinal vertebrae begin pressing on the nerves, pain
can be very severe and may require surgery. Even surgically
treated patients are at risk for spondylosis if inflammation
occurs in vertebrae around the fusion site.
Long-Term Emotional Impact of Scoliosis and Its
Emotional Impact in Childhood. The
emotional impact of scoliosis, particularly on young girls or
boys during their most vulnerable years, should not be
underestimated. Adults who have had scoliosis and its
treatments often recall significant social isolation and
physical pain. Follow-up studies of children who had faced
scoliosis without having strong family and professional
support often report significant behavioral problems.
Fortunately, current treatments are solving many of the
problems that previous generations had to deal with, including
unsightly bracing and extremely painful surgeries with little
Emotional Effects in Adults. Of some
concern are the growing numbers of adults with scoliosis. This
group experiences considerable problems in general health,
social functioning, emotional and mental health, and pain.
Older people with a history of treated scoliosis
may carry negative emotional events into adulthood that have
their roots in their early experiences with scoliosis. Many
studies have reported that patients who were treated for
scoliosis have limited social activities and a poorer body
image in adulthood. Some patients with a history of scoliosis
have reported a slight negative effect on their sexual life.
Pain appears to be only a minor reason for such
Effects on Pregnancies and Reproduction
Women who have been successfully treated for
scoliosis have only minor or no additional risks at all for
complications during pregnancy and delivery. A history of
scoliosis does not endanger the child. Pregnancy itself, even
multiple pregnancies, does not increase the risk for curve
progression. Women who have severe scoliosis that restricts
the lungs, however, should be monitored closely.
Patients with severe deformities, particularly
those with underlying neuromuscular disorders, may develop
what is called restrictive thoracic disease. This term refers
to problems in breathing and, at times, trouble obtaining
enough oxygen due to a smaller chest cavity. This smaller
chest cavity results from the deformities or surgery. The
restricted chest cavity is also less able to expand when
Risks of Cancer from Multiple X-Rays
Some evidence suggests a slightly higher risk
for breast cancer and leukemia in patients who had multiple
x-rays. Risks are highest in patients who had the largest
radiation exposure, such as those who had been surgically
Patients who simply received x-rays for
untreated idiopathic scoliosis, or scoliosis caused by uneven
length of the legs or hip abnormalities have a very low risk
for future complications.
Scoliosis is usually painless. The curvature
itself may often be too subtle to be noticed, even by
observant parents. Some parents may notice abnormal posture in
their growing child that includes:
A tilted head that does not line up over the
A protruding shoulder blade
One hip or shoulder that is higher than the
other, causing an uneven hem or shirt line
An uneven neckline
Leaning more to one side than the other
In developing girls, breasts appearing to be
of unequal size
One side of the upper back is higher than
the other when the child bends over, knees together, with
the arms dangling down
With more advanced scoliosis, fatigue may occur
after prolonged sitting or standing. Scoliosis caused by
muscle spasms or growths on the spine can sometimes cause
pain. Nearly always, however, mild scoliosis produces no
symptoms, and the condition is usually detected by a
pediatrician or during a school screening test.
The severity of scoliosis and need for treatment
is usually determined by two factors:
Both are measured in degrees. These two factors
are usually related. For example, a person with a spinal curve
of 20 degrees will usually have a trunk rotation (ATR) of 5
degrees. These two measurements, in fact, used to be the
cutoff for recommending treatment. However, the great majority
of 20-degree curves do not get worse. Patients do not usually
need medical attention until the curve reaches 30 degrees, and
the ATR is 7 degrees.
Adam's Forward Bend Test. The screening
test used most often in schools and in the offices of
pediatricians and primary care doctors is called the Adam's
forward bend test.
The child bends forward dangling the arms, with
the feet together and knees straight. The curve of structural
scoliosis is more apparent when bending over. In a child with
scoliosis, the examiner may observe an imbalanced rib cage,
with one side being higher than the other, or other
The forward bend test, however, is not sensitive
to abnormalities in the lower back, a very common site
for scoliosis. Because the test misses about 15% of scoliosis
cases, many experts do not recommend it as the sole method for
screening for scoliosis.
Other Physical Tests.
The patient walks on the toes, then the
heels, and then jumps up and down on one foot. Such
activities indicate leg strength and balance.
The doctor will check leg length and look
for tight tendons in the back of the leg, which may cause an
uneven leg length or other back problems.
The doctor will also check for neurological
impairment by testing reflexes, nerve sensation, and muscle
Identifying the Curvature
Proper diagnosis is important. A misjudgment can
lead to unnecessary x-rays and stressful treatments in
children not actually at risk for progression. Unfortunately,
although measurements of curves and rotation are useful, no
test exists yet to determine whether a curve will
Inclinometer (Scoliometer). An
inclinometer, also known as a scoliometer, measures
distortions of the torso. The procedure is as follows:
The patient bends over, arms dangling and
palms pressed together, until a curve can be observed in the
upper back (thoracic area).
The Scoliometer is placed on the back and
measures the apex (the highest point) of the upper back
The patient continues bending until the
curve can be seen in the lower back (lumbar area).
The apex of this curve is also measured.
Measurements are repeated twice, with the
patient returning to a standing position between
If results show a deformity, the patient
will probably need x-rays to determine the extent of the
Some experts believe the scoliometer would make
a useful device for widespread screening. Scoliometers,
however, indicate rib cage distortions in more than half of
children who turn out to have very minor or no sideways
curves. They are therefore not accurate enough to guide
Currently, x-rays are the most cost-effective
method for diagnosing scoliosis. Experts hope that accurate,
noninvasive diagnostic techniques will eventually be developed
to replace some of the x-rays used to monitor the progression
of scoliosis. To date, imaging techniques under investigation
appear to be fairly accurate for detecting scoliosis in the
upper back (the thoracic region), but not scoliosis in the
lower back (the lumbar region).
X-Rays. If screening indicates scoliosis,
the child may be sent to a specialist who takes an initial
x-ray and monitors the child every few months using repeated
x-rays. X-rays are essential for an accurate diagnosis of
They reveal the degree and severity of
They show other spinal abnormalities,
including kyphosis (hunchback) and hyperlordosis (swayback).
X-rays help the doctor determine whether
skeletal growth has reached maturity.
X-rays taken when patients are bending
forward can also help differentiate between structural and
nonstructural scoliosis. Structural curves persist when a
person bends over, and nonstructural curves tend to
disappear. (Muscle spasms or spinal growths may sometimes
cause nonstructural scoliosis that shows a curve on
Children and young adolescents who have mild
curves, and older adolescents, who have more severe
curvatures but whose growth has stopped or slowed, need
x-rays every few months to detect increasing severity. Young
people who are diagnosed with scoliosis should keep their
x-rays indefinitely in case they develop back problems later
in adulthood and need to be re-examined.
Magnetic Resonance Imaging. Magnetic
resonance imaging (MRI) is an advanced imaging procedure that
does not use radiation, as x-rays do. It is expensive,
however, and not generally used for an initial diagnosis. MRI
can, nevertheless, identify spinal cord and brain stem
abnormalities, which some studies indicate may be more
prevalent than previously believed in children with idiopathic
scoliosis. It also may be particularly useful before surgery
for detecting defects that could lead to potential
Protective Measures for Frequent X-Rays
Because frequent x-rays may be required for
young children with scoliosis, parents should be sure that
x-ray technicians take all necessary protective measures.
Experts are concerned about the long-term effects of radiation
on sensitive young organs, particularly about a possible
increase in the risk for cancer. Studies have reported an
increased risk for cancer in women and men who, because of
scoliosis, had been exposed to diagnostic x-rays in their
childhood and adolescence.
X-ray techniques have become safer in recent
years, and technicians can reduce the hazards with the
following simple measures:
Directing x-ray beams through the patient
from back to front, rather than the reverse
Using x-ray filters that absorb some of the
Using fast film to reduce exposure by two to
Placing lead aprons or shields over parts of
the body that are not being x-rayed
Determining the Extent of the Curve
There are various methods for determining and
classifying the extent of the curve.
Cobb Method. The technique known as the
Cobb method nearly always calculates the degree of the
On an x-ray of the spine, the examiner draws
two lines: One line extends out and up from the edge of the
top vertebrae of the curve. The second line extends out and
down from the bottom vertebrae.
The technician then draws a perpendicular
line between the two lines.
Measuring the intersecting angle determines
the degree of curvature.
The Cobb method is limited because it cannot
fully determine the flexibility or the three-dimensional
aspect of the spine. It is not as effective, then, in defining
spinal rotation or kyphosis. It also tends to over-estimate
the curve. Additional diagnostic tools are needed to make a
more accurate diagnosis.
Classifying the Curve. Classification of
the curve allows the doctor to identify patterns that can help
determine treatments, particularly specific surgical
techniques. The following are examples:
King Classification. The King classification
classifies scoliosis curves as one of five patterns, which
can help determine surgical treatments. It has limitations,
however, and is not very useful for advanced surgical
Lenke Classification. Lenke classification
takes more features of the curve into consideration and is
proving to be more reliable. It includes six curve patterns
plus additional factors that modify each of these
Three-Dimensional Modeling Techniques.
Advanced computer modeling techniques are able to create three
dimensional using x-rays or other two-dimensional . They allow
doctors to observe the spinal distortions. Eventually, they
could reduce the number of x-rays needed to monitor scoliosis
and help surgeons determine the best surgical procedures.
Determining the End of Growth
Even if the curve is accurately calculated, it
still remains difficult to predict whether the scoliosis will
progress. A recent report indicates that measuring the nerve
conduction activity of the muscles supporting the spine may
help predict subsequent progression in children with
scoliosis. In addition, computer models are being used to
better predict risk. One approach requires measuring 21
radiographic and clinical indicators and entering them into a
computer program. The technique takes less than 20 minutes per
patient, and studies found it to be up to 80% accurate in
determining progression of curvature.
One way of predicting whether or not the
curvature will progress is knowing when the child will stop
If the child has years to grow, then the
curve has more time to progress.
If the child will stop growing within a
year, then progression should be very slight. (However, some
progression continues in nearly 70% of curves even after the
spine has matured.)
Knowing the child's age is, of course, the first
step in estimating the end of growth. In addition, other
methods can help predict the end of the growth stage. One
method is called the Risser sign, which grades the amount of
bone in the area at the top of the hipbone. A low grade
indicates that the skeleton still has considerable growth; a
high grade means that the child has nearly stopped growing and
the curve is unlikely to progress much further. The Risser
scale differs between genders, and, in boys, a high grade does
not always signify the end of progression.
To Screen or Not to Screen for Scoliosis
Screening programs for scoliosis, which began in
the 1940s, are now mandatory in middle or high schools in many
states, but there is considerable debate over whether
screening should be routine.
Arguments Against Routine Screening.
The U.S. Preventive Services Task Force does not
recommend routine screening to detect adolescent scoliosis for
the following reasons:
Screening tests are not accurate and depend
too much on the skill of the examiner.
Schools often refer children with minor
curves who are not at any risk for a progressive or serious
condition to doctors, and such over-referrals add
considerably to the costs of the health system.
Patients with scoliosis have no greater
danger for significant lung problems than the general
population until their curves reach 60 - 100 degrees, making
early screening unnecessary.
Such programs result in early treatments
that either will not prevent curve progression and surgery
or are unnecessary in the first place since curvatures often
do not progress at all.
Arguments for Routine Screening. The
American Academy of Orthopaedic Surgeons recommends that girls
be screened twice, at ages 10 and 12, and that boys be
screened once, at ages 13 or 14. The American Academy of
Pediatrics recommends, however, scoliosis screening at ages
10, 12, 14, and 16 years. (In one study, over 40% of
high school sophomores with newly diagnosed scoliosis had
shown no signs of the disorder in earlier screening tests.)
Other experts make the following arguments for universal
Universal screening is useful for producing
information on scoliosis that may eventually lead to
knowledge of its cause and ways to prevent it.
Braces have proven to be effective, and
early treatment can be important.
Without screening, the chances are slim that
children with scoliosis will be diagnosed at an early stage
if parents rely only on examinations by a family doctor or
pediatrician. Such doctors often do not even look at backs
and, if they do, they tend to use only the forward bend
test, which is not accurate.
Some experts argue that widespread screening
would be cost effective if schools had reasonable guidelines
for determining which children should see a doctor for further
testing. The following are some suggested guidelines for
determining the need for a doctor referral:
Such guidelines would detect about 95% of all
genuinely serious cases while referring only 3% of all
screened children for follow-up, thereby cutting costs without
The treatments for scoliosis are not always
straightforward. Some young people do not need treatment at
all -- only careful observation. When treatment is necessary,
several options, including braces and various surgical
procedures, can help.
Decision to Treat or Wait
The general rule of thumb for treating scoliosis
is to monitor the condition if the curve is less than 20
degrees. Curves greater than 25 degrees, or those that
progress by 10 degrees while being monitored, may require
treatment. Whether scoliosis is treated immediately or simply
monitored is not an easy decision, however. The percentage of
cases that will progress more than 5 degrees can be as low as
5% in certain cases or as high as 50 - 90%, depending on the
severity of the curve or other predisposing factors:
Age. In general, the older the child the
less likely it is that the curve will progress. Scoliosis in a
child under 10, for example, is more likely to progress than
scoliosis in an adolescent. Experts estimate that curves less
than 19 degrees will progress 10% in girls ages 13 - 15 years
and 4% in children older than 15. (In some rare, severe cases,
a curve may worsen even after a child has received treatment
and stopped growing because of the weight of the body pressing
against the abnormal curve.)
Gender. Girls have a higher risk for
progression than boys.
Location of the Curvature. Thoracic
curves, those in the upper spine, are more likely to progress
than thoracolumbar curves or lumbar curves (those of the
middle to lower spine).
Severity of the Curvature. The higher the
degree of curvature the more likely the chance of progression
and the more likely the lungs will be affected. Some experts
argue that the degree of the curve alone may not identify
patients with moderate and severe scoliosis who are at
greatest risk for complications and therefore need treatment.
For example, spinal flexibility and the extent of asymmetry
between the ribs and the vertebrae may be more important than
the curve degree in predicting severity in this group.
Presence of Other Health Conditions.
Children in poor health may suffer more from stressful
scoliosis treatments than other children. On the other hand,
children who have existing conditions and are predisposed to
lung and heart problems may warrant immediate, aggressive
For example, a young man of 18 who has a
curvature of 30 degrees may require no treatment because his
growth has probably almost stopped, and his gender puts him at
lower risk. A young girl of 10, however, with the same
curvature requires immediate treatment.
In general, the following criteria are used to
determine whether a patient should receive braces and
conservative treatments or surgery:
Braces tend to be used in children with
curvatures between 25 - 40 degrees who still will be growing
Surgery is suggested for patients with
curvatures over 50 degrees in untreated patients, or when
braces have failed. In adults, scoliosis rarely progresses
beyond 40 degrees, but surgery may be required if the
patient is in a great deal of pain or if the scoliosis
causes neurological problems.
The choice may not be so straightforward in
certain cases, and patients should discuss all options with
Predicting the Extent of Curvature
In Children and Adolescents. After a
mild curve is detected, a more difficult step is required:
predicting whether the curve will progress into a more serious
condition. Although as many as 3 in every 100 teenagers have a
condition serious enough to need at least observation,
progression is highly variable and individual.
Doctors cannot rely on any definitive risk
factors for curve progression to predict with any certainty
which patients will need aggressive treatment. Some evidence
suggests the following factors may help determine patients at
lower or higher risk:
Having a greater angle of curvature. For
example, at 20 degrees, only about 20% of curves progress.
Young people diagnosed with a 30-degree curve, however, have
a risk for progression of 60%. With a curve of 50 degrees,
the risk is 90%.
Curvatures caused by congenital scoliosis
(spinal problems present at birth). These may progress
Treatment with growth hormone. (Studies are
mixed on whether this treatment poses any significant risk,
although strict monitoring is still essential in young
patients being given growth hormone.)
Curvatures may be less likely to progress
in girls whose scoliosis was low in the back and whose spine
was out of balance by more than an inch. Height also comes
into play. For example, a shorter-than-average girl of 14 with
low-back scoliosis of 25 - 35 degrees but whose spine is
imbalanced by over an inch would have almost no risk. The same
degree of curvature in the chest region of a tall 10-year old
girl whose spine was in balance, however, would almost
In Adults. In rare cases, unrecognized
or untreated scoliosis in youth may progress into adulthood,
with the following curvatures posing low-to-high risk:
Curvatures under 30 degrees almost never
Predicting progression at curves around 40
degrees is not clear.
Curvatures over 50 degrees are at great risk
Braces and Other Noninvasive
Braces are generally prescribed to prevent
further progression of curves 20 - 25 degrees, and no more
than 40 degrees. Patients should have documented progression
of the curve, and the child should still be growing. Braces
are used to stop progression rather than to reverse a
Results vary widely depending on the length of
time the brace is worn, the type of brace, and the severity of
the curve. Determining how effective braces are has been
difficult for researchers. Most studies evaluate whether the
curve has progressed. There is much less information about
whether brace usage actually reduces the amount of patients
who eventually have surgery.
The great majority of subjects in scoliosis
studies are girls. Limited data suggest that in boys
compliance rates are low, and braces are not effective.
However, compliance with wearing a brace correlates strongly
with success rate.
In overweight patients with adolescent
idiopathic scoliosis, braces appear to be less effective than
in those who are not overweight.
Many experts have questioned whether a brace is
any better than nature in halting curvature progress. Early
studies found that braces were successful in halting
progression in only half of cases (the same rate as no
treatment at all). In recent years, however, braces have
improved. Many now fit under the arms and can be worn under
clothing, so that patients are much more likely to use them
for longer periods during the day, which greatly affects their
Wearing the brace for the prescribed time is
difficult but essential for any success. A team approach, with
several health professionals involved, is beneficial and often
necessary to support the patient through the bracing process.
An orthopedic surgeon interprets the x-rays, assesses the
potential progression of the scoliosis, and plans the
treatment with the patient and family. If a brace is used, an
orthotist measures and fits the patient with the device. A
physical therapist tailors an exercise program best suited for
the patient. A nurse may also coordinate the treatment plans
and provide physical and emotional support.
Types of Braces
Full Torso Brace. A full torso brace
called the Milwaukee brace was the standard treatment until a
decade ago. It is still used particularly for high curves.
The device contains a wide flat bar in front and
two smaller ones in back. These bars attach to a ring around
the neck that has rests for the chin and back of the head. One
study determined that correcting the curve occurs best if the
patient lies on their chest when wearing the brace. Some
researchers suggest that increasing the tension on the chest
straps might add benefit. The brace is also periodically
adjusted for growth.
The brace needs to be worn 23 hours a day, with
relief during bathing and exercise only. Compliance is a major
problem. In one study, only 15% of patients wore the Milwaukee
brace as directed. It is a particularly difficult brace to
endure wearing; one woman who had worn it for 7 years during
adolescence remembered being invisible during her school
years, ignored and shunned by other children.
Thoracolumbar-Sacral Orthoses (TLSO).
Molded braces called thoracolumbar-sacral orthoses (TLSOs),
most often the Boston brace, come up to beneath the underarms
and can be fitted close to the skin so they do not show
beneath clothing. It appears to be effective for mid-back and
lower curves. The risk for curve progression is significantly
higher the less time the brace is worn. These braces have
several problems: they are hot, reduce lung capacity by nearly
20%, and cause mild, temporary changes in kidney function.
Nighttime Braces. The Charleston
Bending brace and the Rosenberg brace are worn only at night.
Some doctors question their value, although they appear to be
suitable for small, flexible curves. In a 2002 study, these
braces were equally effective as the Boston brace. Other
studies have reported success rates of 56 - 66% in patients
who wore the brace as directed. Still, more than 10% of the
patients using either the Boston brace or nighttime braces
eventually needed surgery.
Newer braces are being developed in an attempt
to improve compliance and results. Some examples are:
The Providence brace is a computer-fitted
device that is worn only at night. It is specifically
designed for the individual curvature abnormalities, and
early studies are showing promise.
A bracing method called the SpineCor uses
adjustable bands and a cotton vest that allows flexibility.
The custom-fitted TriaC brace exerts
pressure in specific areas of the back to allow greater
comfort and flexibility. It may be less conspicuous than
some of the older braces.
Studies are needed to determine if these or
other new braces provide any additional value over existing
Braces and Quality of Life
Compliance in wearing the brace varies widely.
Patients are more likely to wear them at night but often wear
them sporadically during the day. Quality of life can vary by
the type of brace worn. In one study, patients who had the
Milwaukee brace reported greater impairment than patients with
the Boston, other TSLO, or Charleston braces. The choice of
brace should be one that will be the most effective for a
particular patient with the lowest impact on the patient's
quality of life. Young people often refuse to wear braces,
even the newer models, and emotional support from family and
professionals is extremely important to help a child accept
the process and stay compliant.
Exercise and Physical Therapy While Wearing
For children who need braces, an exercise
program helps boost well-being, improves compliance with
treatment, and keeps muscles in tone so that the transition
period after brace removal is easier.
An exercise and physical therapy program is
important to maintain or achieve the following:
Proper breathing. In one study, young girls
who wore the Boston brace and performed aerobic exercises
for 30 minutes four times a week had better lung function,
whereas lung function declined in girls who did not
Muscle strength (especially in the abdominal
Flexibility in the spine. One small study
showed that patients who performed exercises improving
flexibility in the torso had less spinal twisting and
Correct posture. Practicing correct posture,
especially in front of a mirror, is an extremely important
part of any physical therapy program. A patient who is
accustomed to a curved spine may have the sensation of being
crooked when first taught to properly align the spine.
Practicing in front of a mirror provides a reality check.
Patients must also learn to conduct daily
activities while wearing the brace. Patients tend to comply
with physical therapy in the period when the brace is first
being used. They typically stop exercising when they have
gotten used to the brace, however, and resume exercising
only near the time the brace is being removed. Patients who
don't stay with the program throughout the duration of brace
use experience a weakening in the back at the time of
Serial casting is something that may be used in
children with infantile scoliosis only. Candidates are
generally those whose scoliosis is progressing. Depending on
how quickly the child is growing, casts are changed around
every two months for children younger than 2, around every 3
months for those aged 3 years, and every 4 months for children
4 years and older.
Alternative Nonsurgical Procedures
Exercise. Exercise has many health
benefits and is important for maintaining strength and muscle
tone and stabilizing weight. Stretching exercises may be
beneficial in children whose scoliosis is due to uneven leg
lengths or a shortened tendon.
ASCO Scoliosis Treatment Method. ASCO
Scoliosis Treatment Method is a Russian approach that consists
of isometric and stretching exercises, vibration, spinal
manipulation, and electrical muscle stimulation. Some U.S.
centers are reporting success in halting curve progression,
but more research is needed to determine the possible benefits
of this method.
Chiropractic Care. Several case reports
suggest that chiropractic manipulation of the spine may help
stop progression of mild curves. However, no rigorous studies
have proved this.
Improving Lung Function
Airway Ventilation at Night. Some
research has focused on the use of airway systems, such as
nasal continuous positive airflow pressure, for patients with
severe scoliosis and reduced lung capacity. Patients use such
systems during the night to force air into the upper airways
and lungs. Such systems also can treat sleep apnea, a common
Breathing Exercises. Breathing
exercises may help improve lung function in children with
scoliosis and signs of lung problems.
Heel Lifts for Secondary Scoliosis
Heel Lifts and Underfoot Wedges. When a
difference in leg lengths causes secondary scoliosis, adding
lifts to the heels or other shoe wedges may be tried. It is
not clear whether these devices reduce spince curvature.
The goals of scoliosis surgery are
Straighten the spine as much as possible in
a safe manner
Balance the torso and pelvic areas
Maintain the correction
It takes a two-part process to accomplish these
Fusing (joining together) the vertebrae
along the curve
Supporting these fused bones with
instrumentation (steel rods, hooks, and other
devices) attached to the spine
There are many surgical variations that use
different instruments, procedures, and surgical approaches to
treat scoliosis. All of the operations require meticulous
skill. In most cases, success depends less on the type of
operation than on the skill and experience of the surgeon.
The cause of scoliosis often determines the type
of procedure. Other determinants include the location of the
curve (thoracic, thoracolumbar, or lumbar); single, double, or
triple curves, and any rotation that may be present; and how
large the curve is.
Parents of patients or adult patients should not
be shy in asking the surgeon and hospital about their
experience with the specific procedures being considered.
Idiopathic Scoliosis. Surgery is
usually recommended for the following children and adolescents
with idiopathic scoliosis:
All young people whose skeletons have
matured, and who have a curve greater than 45 degrees.
Growing children whose curve has gone beyond
40 degrees. (There is still some debate, however, about
whether all children with curves of 40 degrees should have
Neuromuscular Scoliosis (such as
meningomyelocoele and cerebral palsy). If performed, surgery
is done when curving has progressed to 40 degrees or more in
patients fewer than 15 years old. However, this patient group
is considered to be at increased surgical risk, particularly
for patients with feeding problems, malnourishment, or
respiratory difficulties due to the scoliosis. They also have
an increased risk of bleeding complications.
Congenital Scoliosis. These children
are at a higher risk of neurological injury when having
surgery. However, chances for success are higher when surgery
is performed at a younger age.
Adult Scoliosis. Due to the increase
chance of complications, there is more reluctance to perform
surgery on this patient group.
Procedures will differ depending on whether a
child has idiopathic scoliosis, or scoliosis due to muscle and
nerve disorders (such as muscular dystrophy or cerebral
palsy). In the latter cases, children also need a team
approach to reduce their risks for serious complications.
Before the operation, a doctor conducts a
complete physical examination to determine leg lengths, muscle
strength, lung function, and any postural abnormalities. The
patient receives training in deep breathing and effective
coughing to avoid lung congestion after the operation. The
patient should also receive training in turning over in bed in
a single movement (called log-rolling), before the operation.
Psychological intervention, using cognitive-behavioral methods
that help young patients cope, may be very helpful in reducing
anxiety and pain after surgery.
Patients are encouraged to donate their own
blood before the operation, for use in possible transfusions.
The patient should have no sunburn, rashes, or sores on the
back before the operation. These conditions could increase the
risk for infection.
Most scoliosis operations involve fusing the
vertebrae. The instruments and devices used to support the
fusion vary, however.
In the fusion procedure, the surgeon will:
Slice flaps to expose the backs of the
vertebrae that lie along the curve.
Remove the bony outgrowths along the
vertebrae that allow the spine to twist and bend.
Lay matchstick-sized bone grafts vertically
across the exposed surface of each vertebra, being careful
that they touch adjoining vertebrae.
Fold the flaps back to their original
position, covering the bone grafts.
These grafts will regenerate, grow into the
bone, and fuse the vertebrae together.
Graft Materials. A surgeon takes bone
grafts from the patient's hip, ribs, spine, or other bones
(these grafts are called autografts). This is the best quality
bone. However, because autografts are taken directly from the
scoliosis patient, the operation is longer and the patient has
more pain afterward. Researchers are investigating allografts,
bone grafts taken from another living person or a cadaver.
This would reduce the pain and duration of the operation.
Allografts, however, pose an increased risk for infection from
Some surgical centers now perform spinal fusions
in adults using a biologically-manufactured human bone protein
instead of bone grafts. RhBMP-2 (INFUSE Bone Graft) contains a
bone morphogenetic protein (BMP) that helps the body grow its
own bone. A surgeon inserts the protein into a pair of
thimble-like cages, which are implanted between the spinal
vertebrae. The cages help stabilize the spine, while the
protein prompts new bone growth. Doctors hope that this new
procedure can eliminate the pain of autografts and the risk of
infection of allografts. Results from preliminary studies have
been promising. BMP treatments are currently approved only for
Another recent innovation is the use of
bioactive glass in place of an allograft or autograft. In a
study in France, bioactive glass was proven as effective as
bone grafts in idiopathic scoliosis patients undergoing fusion
surgery. There were fewer complications with the bioactive
glass procedures. Further long-term studies will have to
determine if this material is as effective long-term as
traditional bone grafts.
Healing. The healed fusions harden in a
straightened position to prevent further curvature, leaving
the rest of the spine flexible. It takes about 3 months for
the vertebrae to fuse substantially, although 1 - 2 years are
required before fusion is complete. Fusion stops growth in the
spine, but most growth occurs in the long bones of the body
(such as in the legs), anyway. Patients will most likely gain
height from both growth in the legs and from the straighter
Patients may walk at a slightly slower pace
after fusion, but balance may improve, and sports activities
are not restricted after the procedure.
Harrington Procedure. Until 10 years ago,
the standard instruments used in fusion procedures were those
of the Harrington procedure, first developed in the 1960s:
To support the fusion of the vertebrae, the
surgeon uses a steel rod, extending from the bottom to the
top of the curve. (More than one rod may be used depending
on the type of curve, and whether outward curvature of the
spine is present.)
The rod is attached by hooks that are
suspended from pegs inserted into the bone.
Similar to changing a tire, the steel rod is
jacked up and then locked into place to support the spine
securely. The surgeon is then ready to fuse the vertebrae
After this operation, patients must wear a
full body cast and lie in bed for 3 - 6 months until fusion
is complete enough to stabilize the spine.
After 1 - 2 years, the steel rod is not
really necessary, but it is almost always left in place
unless infection or other complications occur.
The Harrington procedure is very difficult to
undergo, particularly for young people, and although the
operation can achieve a 50% correction of the curve, studies
have reported a 10 - 25% loss in this correction over time.
The procedure does not correct the rotation of the spine and,
therefore, does not improve an existing rib hump that was
caused by the rotation. The operation does not interfere with
normal pregnancies and deliveries later in life.
Certain complications may occur from this
About 40% of Harrington patients have a
condition called the flat back syndrome, because the
procedure eliminates normal lordosis (the inward curving of
the lower back). Flat back syndrome from the Harrington
procedure does not cause any immediate pain. In later years,
however, the disks may collapse below the fusion, making it
difficult to stand erect, and the condition can cause
significant pain and emotional distress.
Studies have reported that 5 - 7 years after
their surgery, between a fifth and a third of patients who
had the Harrington procedure experienced low back pain. In
such cases, however, the pain was not severe enough to
interfere with normal activities and did not require
Children younger than age 11 whose skeleton
is immature and who have the Harrington procedure have a
fairly high risk for a specific curve progression called the
crankshaft phenomenon. This condition occurs when the front
of the fused spine continues to grow after the procedure.
The spine cannot grow longer, so it twists and develops a
curvature. However, in one study that followed patients for
5 - 16 years, crankshaft curve progression was moderate,
with the Cobb angle averaging 9 degrees and rotation
averaging 7 degrees.
Cotrel-Dubousset Procedure. The
Cotrel-Dubousset procedure corrects not only the curve but
also possibly rotation, and it does not cause flat back
With this procedure, a surgeon cross links
parallel rods for better stability in holding the fused
vertebrae. Patients often go home in 5 days and may be back in
school in 3 weeks.
The Texas Scottish-Rite Hospital (TSRH)
Instrumentation. The Texas Scottish-Rite Hospital (TSRH)
instrumentation is similar to the Cotrel-Dubousset procedure
in that it uses parallel rods and other devices that reverse
rotation as well as improve curvature. TSRH, however, uses
smooth rods and hooks that are designed to make removal or
adjustment easier later on if complications arise.
Complications are similar to the Cotrel-Dubousset
Additional Forms of Instrumentation.
Other instrumentation procedures have refined the hardware
used in the Harrington and Cotrel-Dubousset operations. Some,
but not all, are listed below:
After surgeons developed Luque
instrumentation to help maintain normal lordosis, experts
hoped that bracing would not be needed. Several studies
showed, however, that without braces, correction was lost
after this operation, and the procedure may have a higher
risk for spinal cord injury than other standard procedures.
Luque instrumentation is used primarily in people whose
scoliosis is due to problems of nerves and muscles, such as
in children with cerebral palsy.
Wisconsin segmental spine instrumentation
(WSSI) is as safe as the Harrington rod and nearly as strong
as the Luque instrumentation.
Instrumentation for Anterior Approach.
The anterior approach, in which the surgeon performs
the operation by opening the chest wall, requires specific
hardware. Halm-Zielke instrumentation, for example, uses TSRH
instrumentation with bone grafts constructed from ribs to prop
open the spaces between the disks. It allows true
three-dimensional curve correction. However, it does not solve
specific problems -- higher risks for kyphosis (an outward
curve) and pseudoarthrosis (a false joint at the fusion site).
Variants using two rod systems, fusion cages, or other
instruments appear to improve this procedure.
The Surgical Approach
Posterior Approach (Through the Back).
Many surgeons use a posterior approach for scoliosis,
which reaches the surgical area by opening the back of the
patient. It has been the gold standard for decades and is
generally used with Harrington instrumentation. The posterior
approach has advantages and disadvantages:
Advantages. Surgeons are familiar with it,
so fusion rates are excellent, curve correction is good, and
it has few complications.
Disadvantages. Preadolescent children are at
risk for the crankshaft phenomenon (a worsening of the
curve) later on. (Newer posterior instrumentation, such as
the Isola instrumentation, may prevent this occurrence.) The
posterior approach also does not always correct
hypokyphosis (the loss of normal outward curvature)
in the thoracic (upper) spine. The procedure is not always
effective for curves in the thoracolumbar region (where the
upper and lower spine meet) and may cause spinal
Anterior Approach (Through the Front).
Increasingly, surgeons are using the anterior approach, in
which the surgeon performs the operation through the chest
wall (called a thoracotomy). With the anterior approach, the
surgeon makes an incision in the chest, deflates the lung, and
removes a rib in order to reach the spine. This rib can be
used during the operation as a strut to support the spine. It
also may be repositioned within the patient until it is used
for bone grafting during fusion.
The anterior approach also has its advantages
Advantages. Because the frontal approach
allows the procedure to be performed higher up in the spine
than with standard procedures, the patient may have a lower
risk for lower-back injury later on. In addition,
transfusion rates are much lower with the anterior approach.
With increasing experience, the anterior approach is as
effective as the posterior approach.
Disadvantages. It is a more recent procedure
than the posterior approach, and, among inexperienced
surgeons, carries a higher risk for complications than in
the more standard posterior approach. Poorer lung function
after surgery has been noted, possibly because the wide
chest incision impairs the chest muscles, which can affect
lung function afterward. Hardware failure rates may also be
higher in the anterior approach than in the posterior
approach. Increasing experience and newer hardware designs
are reducing many of these problems.
The Combined Anterior-Posterior Approach.
The combination approach uses an anterior approach first,
which allows better correction of the problems. The fusion
part of the operation is done with the posterior approach.
This is a very long and complex procedure. It appears to be
safe, however, and is proving to be useful, even in very young
patients, for preventing the crankshaft phenomenon. It also
may correct large rigid curves and specific severe curves in
the thoracic spine.
Researchers are evaluating new approaches to
treating thoracic scoliosis in adolescents and children. A new
device, the vertical expandable prosthetic titanium rib
(VEPTR), is showing promise in the treatment of severe
congenital scoliosis with chest deformities. The device, which
is implanted through surgery, can be adjusted as the child
grows. VEPTR expands the thoracic cavity, thereby correcting
the curvature and allowing spinal, thoracic, and lung growth.
Several studies to date have shown this device is safe and
effective in improving breathing problems and appearance in
Video-Assisted Thoracoscopic Surgery
(VATS). The anterior thoracoscopic surgery uses a
video-assisted anterior approach and recently-developed spinal
instrumentation. Some studies have found no significant
differences between the anterior thoracoscopic and the
traditional posterior approach in terms of kyphosis, coronal
balance, or tilt angle.
This procedure is complicated, and few surgeons
are trained to perform it. The surgery is generally used only
for single curves in the upper back, or for patients with a
curve in the upper back and a compensating curve in the lower
back. Some surgeons are now able to operate on areas below the
diaphragm, including the lumbar spine. The patients must still
wear a brace for 3 months after surgery. Long-term studies are
required to compare results of VATS to those of standard
Advantages of the anterior thoracoscopic
approach include fusion of fewer vertebrae, less blood loss,
quicker recovery time (often out of bed in 2 days), better
cosmetic results, and lower transfusion rate. However, the
operative time is nearly twice as long as that of the
These new treatments have shown some early
positive results, but more research will be needed to
determine their true value.
Complications of All Procedures
Complication rates are high with any of the
procedures, including the standard Harrington method and the
newer Cotrel-Dubousset procedure. A survey of fusion
procedures done between 1993 and 2002 for idiopathic scoliosis
found the complication rates were nearly 15% in children, and
25% in adults.
Complications for all procedures include
allergic reactions to anesthesia and the following:
Bleeding. Standard procedures increase
the risk for major blood loss during the procedure. Patients
are encouraged to donate blood before the operation for use in
possible transfusions. Children sometimes require more than
one transfusion following surgery. Researchers are
investigating various methods for reducing the need for
In one study, patients received erythropoietin
(rhEPO) before the procedure. rhEPO is a hormone that acts in
the bone marrow to increase the production of red blood cells.
Patients who received this hormone, particularly those with
idiopathic scoliosis, needed fewer transfusions and spent less
time in the hospital than those who did not receive rhEPO.
Newer endoscopic techniques are reducing the
need for transfusions.
Postoperative Pain. Some pain always
follows these procedures, requiring intravenous administration
of potent painkillers right after the operation (endoscopic
procedures may require only mild pain relievers). Of some
concern is a study suggesting that the use of NSAIDs, or
nonsteroidal anti-inflammatory drugs (such as aspirin, Motrin,
and Advil), for pain relief right after fusion may increase
the risk for fusion failure. Until more research is conducted,
these common painkillers should not be routinely used
immediately after surgery.
Infection. Infection is always a risk
with any operation. One study reported changes in the immune
system for about 3 weeks after surgery, which indicated a
greater risk for infection. Researchers recommended being very
vigilant for signs of infection, including those in the
pancreas and urinary tract. Doctors also recommend
antibiotics, given by injection for 2 - 5 days after surgery
and by mouth for 1 - 2 weeks longer.
Nerve Damage. Patients often worry about
neurological injuries, but the risk is actually very low. In
general, nerve injury occurs in 1% of patients, with the risk
highest in adults. If neurological damage occurs, it most
often causes muscle weakness. Paralysis is very rare and can
be prevented using monitoring techniques during the operation.
Nearly all monitoring procedures use a so-called wake-up test,
in which the patient is brought out of anesthesia during or at
the end of the procedure and assessed for sensations to be
sure no injury has occurred. One simple method is to wake
patients up in the middle of their operations and ask them to
wiggle their toes. More sophisticated methods measure the
electrical activity of the spinal cord; if the monitor
indicates a fall in electrical response and possible injury,
the surgeon makes adjustments to avoid further damage to the
Pseudoarthrosis. If the fusion fails to
heal, pseudoarthrosis, a painful condition in which a false
joint develops at the site, may develop. In one study,
teenagers who smoked and heavier adolescents (over 154 pounds)
who had hyperkyphosis (hunchback) were at higher risk for this
complication. The anterior approach may pose a higher risk for
pseudoarthrosis. One study reported that pseudoarthrosis may
be undiagnosed, and rates may average 20% after surgery,
therefore acting as a major contributor to post-surgery
Disk Degeneration and Low Back Pain.
Fusion in the lumbar area produces great stress on the lower
back and eventually can cause disk degeneration. Loss of trunk
mobility, balance, and muscle strength from surgical
treatments can also cause lower back pain and chronic problems
in future years. Patients who are surgically treated with
fusion techniques lose flexibility; their back muscles may be
weakened if they were injured during surgery. In most cases,
however, the consequences are mild to moderate.
Lung Function. Some patients may
develop serious lung problems after surgery. These
complications are highest in children whose scoliosis is due
to neuromuscular problems, such as spina bifida, cerebral
palsy, or muscular dystrophy. Lung problems can develop up to
1 week after surgery. Lung function may not become completely
normal until 1 - 2 months after surgery.
Other Complications. Other problems can
include, but are not limited to, the following:
Hooks dislodging or a fused vertebra
Pancreatitis (inflammation of the pancreas).
Among adolescents, this complication tends to occur more
often among those who are older or who have a lower body
Patients must perform breathing and coughing
exercises shortly after the procedure and continue them
through the recovery process to rid the lungs of congestion.
The patient is usually able to sit up the day after the
operation, and most patients can move on their own within a
week. A brace may be necessary, depending on the procedure.
With the anterior approach in the upper back, patients may
have some trouble with activities involving the arms and
hands, such as tying shoes and cutting food. In one study,
however, occupational therapy using stretching and
strengthening exercises allowed for full resumption of daily
activities, including dressing, bathing, and grooming, within
Patients are often concerned that surgery will
stiffen their backs, but most cases of scoliosis affect the
upper back, which has only limited movement, so that patients
do not notice much difference. It may take a year or more for
muscle strength to return. In some cases, the operation cannot
completely correct the curve, and one leg may be shorter than
the other. Heel lifts may help in this case.
Revision (Salvage) Surgery
Patients may need a corrective procedure called
revision or salvage surgery, usually for one of these
Minimally Invasive Surgery
Growing Rod Technique. This technique
is used for very young children in whom bracing has not
helped. Instead of doing spinal fusion, doctors surgically
insert a rod into the patient's back. Additional surgeries are
performed every 6 months to extend the rod so that the spine
can continue to grow. Some growing rod techniques use a single
rod, while others use two rods. Studies suggest that dual rods
are stronger than single rods, which may help provide better
spinal stability and correction.
Vertebral Body Stapling and Anterior Spinal
Tethering. These fusionless procedures are performed with
an anterior approach surgery and without fusion. Vertebral
body stapling is an experimental technique that may prevent
curve progression in some young patients with curves less than
50 degrees. It involves stapling the outer curve of the side
of the spine facing the chest, which helps stabilize and
reduce progression of the inner curve. The procedure uses a
special metal device that is clamp-shaped at body temperature,
but can be straightened when subjected to cold temperatures
and inserted into the spine. When warmed up, the staple
returns to its clamp shape and supports the spine. While
short-term results have been favorable, long-term results are
not yet available.
Treatment for Adult
Adults who were treated with surgery for
scoliosis in their youth are at risk for disk degeneration and
spinal fusion failure.
In most adults with previous scoliosis, moderate
exercise is not harmful and is extremely important for
maintaining healthy, supportive muscles, and preventing disk
degeneration. However, people who have only one or two mobile
lumbar vertebrae below the area that was fused during surgery
should avoid activity or exercise that causes excessive
twisting on the spine. Some experts believe this may
accelerate spinal degeneration.
Nonsurgical Treatment of Adult Scoliosis
In most cases of adult scoliosis, nonsurgical
care is preferred, if possible. This can include patient
education, exercises, and medical treatments. Braces are not
One center reported that epidural steroid
injections were a beneficial alternative to surgery in
patients with degenerative lumbar scoliosis.
Surgical Treatment in Adult Scoliosis
Candidates for Surgery. In general, pain
is the most common reason for surgery in adult scoliosis.
Surgery may be recommended in the following cases:
Curvatures over 50 degrees with persistent
Curvatures over 60 degrees (surgery is
almost always recommended in this case)
Progressive mid and low back curve or low
back curve with persistent pain
Reduced heart and lung function; most
surgeons, however, will not operate on adults with severely
impaired lung function and heart failure. Once this has
occurred, surgery will not help improve lung capacity, and
may cause the condition to worsen, at least temporarily.
Significant deformity is present; adults
should not expect to achieve a completely straight spine,
however. There is a high risk for nerve damage if the spine
is over-corrected, and an adult spine is less flexible than
a child's. Nevertheless, the correction usually achieves an
acceptable cosmetic improvement.
Surgeons prefer to operate on adults under 50
years old, although surgery may be appropriate in some older
Standard Scoliosis Procedures in Adult
Scoliosis. The procedures involve the following, depending
on whether the patient had been previously treated or not:
In patients who have not had previous
treatment, and who have degenerative lumbar scoliosis, the
procedure is often a diskectomy (removal of the diseased
disks) followed by scoliosis procedures (instrumentation and
In patients with previously treated
scoliosis, the only remedy is removal of the old
instrumentation, extension of the fusion, and implementation
of new instrumentation and bone grafts.
Surgical procedures in adult scoliosis are
complex, and are undertaken only after careful consideration
and all nonsurgical methods have been exhausted. Adults have a
much higher risk than children for complications including
pneumonia, infection, poor wound healing, and persistent pain.
In addition, procedures in adults often involve fusion in
lumbar and sacral areas (the low back), which can cause
several complications. Some experts believe that the risks of
operations in this area nearly always outweigh any benefits in
adults. Most studies on adults have also reported low success
Others argue that without an operation, the back
will become unstable and painful. In addition, most studies on
adults report on procedures using the old Harrington
instrumentation techniques. Advances in instrumentation are
increasing success rates in adults. In a recent study, for
example, adults who underwent anterior fusion and
instrumentation had excellent results. In another study of
newer generation instrumentation, 87% of adult patients
Wedge Osteotomy. Researchers are
investigating wedge osteotomy in patients with mature spines,
as corrective surgery and as an alternative to braces. In this
procedure, a surgeon cuts wedges of bone from the concave side
of the curve. The surgeon then straightens the spine by
inserting a temporary rod and closing the cut sections. The
patient needs to wear a brace and restrict activity for about
12 weeks or until the bone has healed. The patient can resume
normal activities when a surgeon removes the rod, and the
spine is mobile.
Aebi M. The adult scoliosis. Eur Spine J.
Akbarnia BA, Marks DS, Boachie-Adjei O, Thompson
AG, Asher MA. Dual growing rod technique for the treatment of
progressive early-onset scoliosis: a multicenter study.
Spine. 2005;30(17 Suppl):S46-S57.
Budweiser S, Moertl M, Jrres RA, et al.
Respiratory muscle training in restrictive thoracic disease: a
randomized controlled trial. Arch Phys Med Rehabil.
D'Astous JL, Sanders JO. Casting and traction
treatment methods for scoliosis. Orthop Clin North Am.
Everett CR, Patel RK. A systematic literature
review of nonsurgical treatment in adult scoliosis.
Spine. 2007;32(19 Suppl):S130-134.
Gao X, Gordon D, Zhang D, et al. CHD7 gene
polymorphisms are associated with susceptibility to idiopathic
scoliosis. Am J Hum Genet. 2007;80(5):957-965.
Guille JT. Fusionless treatment of scoliosis.
Orthop Clin North Am. 2007;38(4:541-545.
Hedequist DJ. Surgical treatment of congenital
scoliosis. Orthop Clin North Am.
Hell AK, Campbell RM, Hefti F. The vertical
expandable prosthetic titanium rib implant for the treatment
of thoracic insufficiency syndrome associated with congenital
and neuromuscular scoliosis in young children. J Pediatr
Orthop B. 2005;14:287-293.
Ilharreborde B, Morel E, Fitoussi F, et al.
Bioactive glass as a bone substitute for spinal fusion in
adolescent idiopathic scoliosis: a comparative study with
iliac crest autograft. J Pediatr Orthop.
Latalski M, Fatyga M, Gregosiewicz A. The
vertical expandable prosthetic titanium rib (VEPTR) in the
treatment of scoliosis and thoracic deformities. Preliminary
report. Ortop Traumatol Rehabil. 2007;9(5):459-466.
Lenssinck ML, Frijlink AC, Berger MY, et al.
Effect of bracing and other conservative interventions in the
treatment of idiopathic scoliosis in adolescents: a systematic
review of clinical trials. Phys Ther.
Lonner, B. S. Emerging minimally invasive
technologies for the management of scoliosis. Orthop Clin
North Am. 2007;38(3): 431-440.
Luhmann SJ, Bridwell KH, Cheng I, Imamura T,
Lenke LG, Schootman M. Use of bone morphogenetic protein-2 for
adult spinal deformity. Spine. 2005;30(17
Motoyama EK, Deeney VF, Fine GF, et al. Effects
on lung function of multiple expansion thoracoplasty in
children with thoracic insufficiency syndrome: a longitudinal
study. Spine. 200631(3):284-290.
Patil CG, Santarelli J, Lad SP, et al. Inpatient
complications, mortality, and discharge disposition after
surgical correction of idiopathic scoliosis: a national
perspective. Spine J. 2008 Mar 19 [Epub ahead of
Richards BS, Vitale M. Screening for Idiopathic
Scoliosis in Adolescents: Information Statement.
AAOS-SRS-POSNA-AAP. Available online.
Rose PS, Lenke LG. Classification of Operative
Adolescent Idiopathic Scoliosis: Treatment Guidelines.
Orthop Clin N Am. 2007;38:521-529.
Sarwark J, Sarwahi V. New strategies and
decision making in the management of neuromuscular scoliosis.
Orthop Clin North Am. 2007;38(4): 485-496.
Shaughnessy WJ. Advances in scoliosis brace
treatment for adolescent idiopathic scoliosis. Orthop Clin
North Am. 2007;38(4):469-475.
Thompson GH, Akbarnia BA, Kostial P, Poe-Kochert
C, Armstrong DG, Roh J, et al. Comparison of single and dual
growing rod techniques followed through definitive surgery: a
preliminary study. Spine. 2005;30(18):2039-2044.
U.S. Preventive Services Task Force.
Screening for Idiopathic Scoliosis in Adolescents: A Brief
Evidence Update for the U.S. Preventive Services Task
Force. June 2004. Agency for Healthcare Research and
Quality, Rockville, MD.
Waldhausen JH, Redding GJ, Song KM. Vertical
expandable prosthetic titanium rib for thoracic insufficiency
syndrome: a new method to treat an old problem. J Pediatr
Yuan N, Fraire JA, Margetis MM, Skaggs DL, Tolo
VT, Keens TG. The effect of scoliosis surgery on lung function
in the immediate postoperative period. Spine.