Adolescent Idiopathic Scoliosis
Often learning your child has adolescent idiopathic scoliosis (AIS) takes a parent by surprise.
Because AIS onset is related to age, your child may have passed one or more scoliosis evaluations in the past. The good news is that now more than ever, research exploring the cause of
and genetic basis for AIS is more robust than ever, and there is a growing clinical interest
among physicians who seek to help you successfully manage your child’s disease.
What Is AIS?
AIS is by far the most common type of scoliosis, affecting children between ages 10 to 18; it’s
found in as many as 4 in 100 adolescents. In general, AIS curves progress during the rapid
growth period of the patient. While most curves slow their progression significantly at the time of
skeletal maturity, some, especially curves greater than 60o, continue to progress during adulthood. Many theories exist with regard to the cause of AIS including hormonal imbalance,
asymmetric growth and muscle imbalance. Although the cause of AIS remains elusive, we have
methods of estimating the risk for curve progression of scoliosis and good methods of treatment.
Genetic Connection
“Idiopathic” means that the condition has no identifiable causes although significant research is
ongoing, including the genetic basis for AIS. Approximately 30% of AIS patients have some
family history of scoliosis, which would indicate a genetic connection. Many Scoliosis Research
Society members are working to identify the genes that cause AIS, and this knowledge continues to expand at a rapid pace. A genetic screening test, called the ScoliScore™, is available as
an adjunct to clinical and x-ray information to determine AIS’ risk of progression.
Symptoms
Patients with AIS typically have no pain or neurologic abnormalities (like weakness) and exhibit
a normal appearance when viewed from the side, however, several visible symptoms are associated with AIS:
 Rib “hump”—A prominence on the back or a rib hump secondary to the rotational aspect of the scoliosis; the most visible sign of scoliosis (see figures 1C and 1D).
 Shoulder height asymmetry—Shoulder height asymmetry is indicated when one
shoulder appears higher than the other (see figure 1A).
 Torso “lean”—A shift of the body to the right or the left can occur especially when there
is a single curve in the thoracic (chest-part) or the lumbar (lower back) of the spine without a second curve to help balance the patient. This often appears as some waistline
asymmetry in which one hip appears to be higher than the other and may result in one
leg appearing longer than the other (see figure 1B).
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Lower Back Pain
When scoliosis begins in adolescence, patients often report some back pain, typically in the
lower back. However, the general medical consensus is that spine curvature is probably not the
cause of lower back pain in most adolescent scoliosis patients. Much of the preteen and teen
population experiences adolescent back pain due to participation in athletic activities without
having proper core abdominal and back strength or hamstring flexibility. Also, spine curvature
rarely places pressure on organs, like the lung and heart, or cause symptoms like shortness of
breath. If these symptoms do occur, however, further evaluation and testing may be necessary.
Diagnostics
Postural Screening Exam
At the physician’s office, scoliosis is evaluated by observing the adolescent’s posture in a
360ºfashion. The examiner checks to ensure that neck, head and pelvis are midline and assesses body symmetry elsewhere: shoulders, scapulas, legs, arms, hip and more. (See video
A.)
Spine Exam
After a thorough patient history is given, the patient will be assessed using the following
measures (See video B.):
• Adams forward bend test with an inclinometer, which helps the doctor to better understand
amount of torso asymmetry.
• Assessment for ligament laxity for connective tissue disorders
• Neurologic exam
Imaging Evaluation
Figure 2. A) AP radiograph, B) Lateral radiograph, C) Cobb method
Standing X-ray
Scoliosis is defined with radiographs that can include a standing x-ray of the entire spine looking
both from the back (see Figure 1A), as well as from the side(see Figure 1B). Lead shields pro-
tect the patient while allowing for a clear view of the spine. Your physician will be able to measure the radiographs to determine curve magnitude, which is measured in degrees using the
Cobb method (see Figure 1C). A straight spine has a curve of 0º; any curve greater than 10ºis
considered scoliosis. Between 0ºand 10ºis considered “postural asymmetry” which is not true
scoliosis. The way a patient stands at the time of an x-ray or many other factors can cause a
slight curvature. The lateral radiograph is used to determine the thoracic kyphosis (or roundback
appearance) and the amount of lumbar lordosis (swayback).
Additional X-rays
Additional x-rays can be performed to determine the flexibility of the curvature (how much it
straightens). X-rays can be taken in which the patient lays on the table and bends to the right
and then to the left (see Figure 2).Traction films are taken with the patient's arms and legs
pulled to stretch the spine out.
Figure 3. Flexibility radiographs
MRI Study
A magnetic resonance imaging (MRI) study of the spine is not routinely used for AIS patients.
An MRI is usually ordered if your physician finds some subtle neurologic abnormalities on physical examination, or if you have significant pain or an "atypical" curve pattern. The likelihood of
having something abnormal on the MRI is very small.
Measuring Growth Potential
Since scoliosis curves grow larger during rapid growth, the potential for growth is evaluated taking into consideration the patient's age, the status of whether females have had their first men-
strual period, as well as radiographic parameters. In general, girls grow until 14 years of age,
while boys grow until 16 years of age. Girls grow very rapidly until their first menstrual period,
and then their growth generally slows down. Adolescents continue to grow until approximately 2
years after their first menstrual period.
X-rays of the spine, pelvis, and hand/wrist are used to determine growth. The Risser grading
system is used to determine a child's skeletal maturity (how much growth is left) on the pelvis,
which correlates with how much spine growth is left. The Risser grading system rates a child's'
skeletal maturity on a scale of 0 to 5. Patients who are Risser 0 and 1 are growing rapidly, while
patients who are 4 and 5 have stopped growing. Generally, patients who are being treated in a
scoliosis clinic will have their height measured at each visit to help determine growth potential.
Figure 4. Risser Grading System
Treatment Options
Treatment of AIS is based on the risk of curve progression and falls into three main categories:
observation, bracing, and surgery.
Observation
Observation is used for patients whose curves are less than 25 to 30º and are still growing —or
for curves less than 45ºin patients who have completed their growth. Scoliosis surgeons often
observe the scoliosis every few years after patients complete their growth to make sure it does
not progress into adulthood. AIS patients with curves greater than 50°are likely to increase into
adulthood at a rate of 0.5°to 2°per year. For this reason, adult scoliosis specialists should monitor the curves in such patients into adulthood.
The Case for the Brace: It works!
The job of a scoliosis brace is to halt or slow progression of the curve – with an ultimate goal of
avoiding a spinal fusion surgery (and the recovery and limitations that go with it). Over the years
the design of scoliosis braces has evolved, resulting in greater effectiveness with a lower profile.
A recent study by the U.S. National Institutes of Health provides strong evidence of how bracing
effects curve progression. Of patients randomly assigned to wearing a brace, 75%
had curves that did not progress to the 50°threshold for surgery at skeletal maturity. Only 42% of patients who did not wear a brace were not surgical candidates. The results of the Bracing in Adolescents with Idiopathic Scoliosis Trial (BrAIST) study
were published in The New England Journal of Medicine (Oct. 17, 2013), and make a compelling “case for the brace.”
Frequent wearers, better outcomes…
The BrAIST study used temperature sensors in the braces to keep account of brace wear. The
findings showed that the amount of time the brace is worn correlates to its effectiveness; patients who wore the brace for less than 6 hours a day had roughly the same success rate as
those patients who did not wear the brace at all! Those who wore the brace more than 13+
hours a day had a success rate of 90% or higher.
Reference:
Weinstein SL, Dolan LA, Wright JG, Dobbs MB. Effects of bracing adolescents
with idiopathic scoliosis. N Engl J Med. 2013; 369:1512-1521.
http://www.nejm.org/doi/pdf/10.1056/NEJMoa1307337. Accessed July 24, 2015.
Figure 5. The X-ray and brace of a young woman with
scoliosis. A T-shirt is usually worn beneath the brace.
The brace is usually custom-made to provide appropriate
correction.
Figure 6. X-rays before and after brace placement
showing correction of the thoracic and lumbar
curves.
Surgery
Figure 7. A) Front and side x-rays of a patient with adolescent idiopathic scoliosis in her
thoracic spine. B) Postoperative correction through a posterior approach using 2 rods
and pedicle screws.
Surgical treatment is often recommended for patients whose curves are greater than 45o while
still growing, or are continuing to progress greater than 45o when growth stopped. Fusion surgical treatment today uses metal implants that are attached to the spine, and then connected to a
single rod or 2 rods. Implants are used to correct the spine and hold the spine in the corrected
position until the instrumented segments fuse as a bone. The goal of surgery is to:
1) Prevent curve progression
2) Obtain some curve correction
The surgery can be performed with either a posterior or anterior approach:
Posterior approach— A straight incision is made along the midline of the back (See Figure 7).
This approach is used most often in the treatment of AIS and can be effective for all curve types.
Anterior approach—A similar (straight) incision is made through front of the spine (anterior approach (Figure 8). This approach is an option in cases where a single thoracic curve or a single
lumbar curve is being treated.
Post-surgery typical timeline
3-6 days:
10-14 days:
3-4 weeks:
3-6 months:
Hospital stay
Most children will no longer need pain medications
Patient can perform regular daily activities and typically returns to school
Depending on the patient’s activities, full participation is allowed.
Figure 8. A) Front and side s-rays of a patient with adolescent idiopathic scoliosis in her thoracic
and lumbar spine. B) Post-operative x-rays showing instrumentation placed via an anterior (side)
approach.
Alternative Treatment
Alternative treatments to prevent further curve progression like chiropractic medicine and yoga
have not demonstrated any scientific value in treating scoliosis. However, these and other
methods may provide some physical benefit to the patient (e.g., core strengthening and symptom relief). Physiotherapy scoliosis-specific exercises are increasingly used in conjunction with
bracing in the treatment of progressive idiopathic scoliosis. The combination of the 2 may offer
advantages over more simplified treatment plans. Scoliosis Research Society (SRS) supports
pilot research studies for the role of exercises in scoliosis treatment.