Adolescent Idiopathic Scoliosis

Idiopathic means the abnormal curve develops for unknown reasons. There is undoubtedly a genetic pre-disposition for some adolescents to develop AIS. Three to five percent of adolescents will be found to have some form of scoliosis. Most of these children will be girls, in which curves may be more progressive.

Symptoms
Symptoms of scoliosis include back pain, leg length discrepancy, an abnormal gait, and uneven hips. Patients with AIS may have one shoulder higher than the other, a "prominent" shoulder blade and rib cage when bending forward, and visible curving of the spine to one side. Often the first indication of AIS is when an adolescent or parent notices that clothes no longer fit correctly (for example, the legs of pants may seem uneven).

It is important to seek treatment for AIS because progressive scoliosis, left untreated, can result in significant deformity. The deformity can cause marked psychological distress and physical disability, especially among adolescent patients. Additionally, the deformity can have serious physical consequences.

As the vertebrae (spinal bones) rotate, the rib cage is affected, which in turn can cause heart and lung compromise (i.e. shortness of breath). When progressive scoliosis affects the lumbar spine the pain can be debilitating.

Diagnosis
Dr. Lonner’s assessment of the child’s condition will include medical history, physical and neurological exam, and diagnostic tests.

Medical history may include questions about the parent’s genealogy. Are there other family members with scoliosis? If so, how did the scoliosis progress and what treatment was provided? Dr. Lonner will check for any underlying medical condition that might otherwise be causing the scoliosis. In addition, the patient’s age, onset of puberty, and age at which a young woman has her first period, will help us to determine the number of years that remain before the child reaches skeletal maturity. At skeletal maturity curve progression may stop as long as the curve is less than 40-45 degrees. The curve may continue to progress throughout adulthood, if the curve exceeds 40-45 degrees.

During the physical and neurological examinations Dr. Lonner will learn about the patient’s health and general fitness. These exams provide the physician with a “baseline” from which future curve progression can be measured. A typical examination may include the following:

Table 1

Examination	Description
Physical assessment	The physician looks for asymmetry of the trunk such as uneven shoulders or hips, humpback, or listing to one side.
Cardiopulmonary	Testing of the function of the heart and lungs.
Adam’s Forward Bending Test	The patient bends forward at the waist, with arms extended forward. The physician looks for asymmetry thoracic prominence (such as a shoulder blade), or a lumbar prominence.
Leg length	Both legs are measured to determine if they are of equal length.
Plumb line	A plumb line is "dropped" from the C7 vertebra (in the neck) and is allowed to hang below the buttocks. In scoliosis the line does not hang between the buttocks.
Range of motion	The physician measures the patient’s ability to perform flexion, extension, bending, and rotation movements.
Palpation	The physician "feels" for abnormalities. Perhaps the ribs are more prominent on one side.
Neurological assessment	In addition to testing reflexes, the physician will want to know if the patient’s symptoms include pain, numbness, tingling, extremity weakness or sensation, muscle spasm, and bowel/bladder changes.

Diagnostic tests include the following:

Table 2

Diagnostic Test	Description
Scoliometer	A scoliometer is used to measure a rib hump while the patient is bent at the waist.
X-rays (radiographs)	X-rays may include an upright lateral view of the spine and side bending.
Cobb Angle Measurement	This test uses a full-length anterior to posterior x-ray to calculate the angle of the curve(s).
Risser Sign	An x-ray to provide information about skeletal maturation. The Risser Sign looks at the iliac crest growth plate, a fan-shaped part of the pelvis. The crest fuses with the pelvis at maturity.
Nash-Moe	A technique used to measure vertebral rotation. The rotation of the vertebral pedicle is measured by dividing the vertebral body into segments.
Lenke Classification	Doctors primarily use one of two classification schemes: King or Lenke. At our practice we usually use the Lenke Classification System. The System helps surgeons to determine what levels of the spine to fuse and instrument.

Non-Surgical Treatment
Some cases of AIS can be treated non-surgically and others require surgical intervention.

Small curves (those less than 15-20 degrees) are observed for possible progression over a period of time. At this stage, no specific treatment is needed. Larger curves (those between 20-40 degrees) will require bracing to prevent further progression of the curve.

Some adolescents find wearing the brace 16 to 23 hours every day difficult. Braces can be uncomfortable, unattractive, hot, and can make a child self-conscious even though well disguised under clothing. However, when bracing works and surgery is avoided, the commitment required is worthwhile. At this point a carefully designed exercise program may also be recommended.

Unfortunately, some curves do not respond to bracing. Cervicothoracic curves (from the middle of the back up into the neck) and curves greater than 40 degrees tend not to respond well to bracing. Also, older patients who are closer to skeletal maturity may not respond to bracing.

Surgical Treatment
Surgery may be recommended for curves in excess of 40 degrees. Surgery for scoliosis involves special surgical implants such as rods, hooks, screws, and wires. The goal is to straighten and balance the spine and secure it in place (fusion) so curve progression stops while skeletal maturity is reached. Surgery does not cure scoliosis; it is simply a way to correct the curve and manage the progression of the disease to avoid greater deformity.

Spine surgeons utilize various surgical procedures to treat AIS. The overall goals are always the same, but the techniques and instrumentation used will vary from case to case. Dr. Lonner may perform the procedure from the front (anterior) or from the back (posterior). He may even make extensive use of minimally invasive techniques.

For those patients who are surgical candidates, a number of approaches are available.  The approach best suited for the individual is chosen by Dr. Lonner based on the size of the curvature, the extent of the curvature (number of levels of the spine involved), the specific location of the curvature, as well as the age of the patient.  Each approach has its distinct advantages that make it suited for the individual patient.  The thoracoscopic approach allows for correction of thoracic curvature in the adolescent patient. This is done through the side of the chest cavity with very small incisions.  The advantage of this approach is that minimal scarring occurs and the pain after surgery is less than with traditional approaches.  In addition, this technique is associated with less blood loss and fewer levels of the spine being fused than with other techniques.  This approach is not for all patients and Dr. Lonner will discuss the application of this technique when appropriate (see article on thoracoscopic surgery).

The most common approach to adolescent idiopathic scoliosis is the posterior (back) approach.  In recent years, pedicle screws have been applied to the thoracic and lumbar spine allowing for improved correction and restoration of spinal balance.  The use of pedicle screws also provides very strong fixation allowing patients to get back to activities within 2-3 months after surgery. In the past, using hooks for fixation, activities were restricted for a minimum of 6 months.  In some patients, a combined anterior (front) and posterior (back) approach is required in order to address very severe curves over 75 or 80°.  The anterior approach is done either with a thoracoscopic technique or for lumbar curves with a small incision, open technique that allows the spine to be made more flexible. This is done by removing discs and placing bone graft into the disc spaces and then combining that with a posterior technique in which instrumentation using screws is performed.  Typically, a curve of 90° is brought down to 15° following this type of approach.  Curvature of 50° is brought down to under 10° with all the techniques described above.

Case Example #1

This 12 year old girl with a 55° idiopathic scoliosis was treated with minimally invasive thoracoscopic surgery. This resulted in a correction of the thoracic curvature to under 15°.  Note that an advantage of this technique is that the lumbar spine is avoided, maintaining flexibility of the spine and resulting in balanced correction.  Fusing the thoracic spine without fusing the compensatory lumbar curvature is termed selective thoracic fusion.

Case Example #2

This 14 year old girl underwent anterior spinal fusion with instrumentation to correct a 47° thoracolumbar curve.  The thoracic curvature was left unfused since it was compensatory and not a true structural curvature. This selective thoracolumbar fusion resulted in correction to under 10°.

Case Example #3

This 12 year old girl had double structural curvature, both over 90°.  With a combined anterior-posterior approach, the curves were both corrected to under 15°.  The patient returned to full activity 4 months after surgery.

Case Example #4

This 18 year old young woman from Taiwan presented with a 100° curvature. This was treated with a thoracoscopic release and fusion to make the spine more flexible followed by posterior fusion done as one procedure. Note the marked correction of this severe curvature and the clinical result shortly after surgery. The incision is noticeable since the clinical photograph was taken within two weeks after surgery. This will fade over several months following surgery.

Conclusion
Left untreated, adolescent idiopathic scoliosis can cause significant physical deformity, debilitating pain, and psychological distress. However, proper treatment and care for AIS can prevent further curve progression and stabilize the spine while your child grows. At Scoliosis Associates, we are specialists in treating scoliosis, and we can discuss the risks and benefits of different treatment options with you, so that both you and your child are well informed.

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