Adolescent Idiopathic Scoliosis—What Is It? How Is It Treated?

What is Adolescent Idiopathic Scoliosis?

The term Adolescent Idiopathic Scoliosis (AIS), is best understood by explaining each individual word:

  • Adolescent is typically used to describe patients between 10 and 18 years of age.
  • Idiopathic means there is no identifiable cause of the condition.
  • Scoliosis means a sideways (lateral) curve of the spine.

Thus, AIS is a sideways curve of the spine, occurring in an adolescent, and without an identifiable cause.

Who Typically Develops AIS?

AIS generally occurs in adolescents aged ten and above, though younger children and adults can also develop Idiopathic Scoliosis.

While three to five percent of adolescents develop some form of scoliosis, girls are at a higher risk. Girls make up approximately seventy percent of AIS patients. In addition, an adolescent female patient’s spine curvature is more likely to be progressive.

What are Some Signs of AIS?

The first signs of AIS are often visual. One shoulder or hip may appear to be higher than the other, and the waist may appear uneven.  The patient may also have a modest “hump” on his or her back due to one shoulder blade being more prominent than the other. In addition, the ribs on one side may be more prominent and the legs may seem to be different lengths.  Sometimes, the first sign that a person may have AIS is when he or she comments that one leg of their jeans seems longer than the other (this is due to the spinal curve causing the waist to  be uneven).

How Big Might the Curve Be?

In some AIS patients the sideways curve may be small, perhaps less than twenty degrees. Other patients may have larger curves, from twenty to forty degrees, and occasionally curves progress to a far more serious degree of far beyond forty degrees.

The curvature may worsen as the adolescent grows, especially during growth spurts. For this reason, early detection is important so that the patient’s growth can be monitored by a doctor.

Is AIS Painful?

Adolescent Idiopathic Scoliosis does not usually cause pain in its early stages, especially if the curve remains relatively small.  If the curve becomes more severe, a patient may experience moderate to severe back pain.

Can AIS Cause Other Problems?

Often the biggest challenge of AIS is that it can be emotionally upsetting for the adolescent. Adolescence is a difficult time of life to begin with, and having a misshapen spine that changes the way the body looks can add to the difficulty.

If the spine curvature causes the hips to be uneven, this can affect the patient’s gait, making it harder for him or her to participate in athletic activities that require running.

In very rare instances, if the curve progresses to a very serious degree, the curve may also affect the functioning of the lungs or the heart.

Image of a spine with scoliosis

How Will A Doctor Diagnose AIS?

To determine if a patient has AIS, the doctor will usually begin with a simple physical exam.  The doctor will examine the patient while he or she is standing, to see if there are any signs of physical asymmetry (for example, uneven shoulders or hips).

The doctor may carry out a Forward Bending Test. The patient will bend at the waist, extending the arms forward. This test can reveal an asymmetry or an abnormal prominence that is not visible when the patient is upright.

Another test that may reveal scoliosis is a plumb line test. If the spine is straight, a plumb line dropped behind the patient from the base of the neck (the C7 vertebra) will hang between the patient’s buttocks. If it hangs to either side, the spine may be curved.

The doctor may also feel for abnormalities such as a prominent rib or shoulder blade. And, the doctor may also measure the length of the legs to determine if they are equal or not.

In addition to the physical exam, the doctor will likely order x-rays.  An upright PA x-ray can reveal a curvature of the spine. The x-rays can be used to calculate the degree of a curve (a Cobb Angle Measurement), and can even show if the patient is likely to continue growing (which will influence the extent to which the curve is likely to progress).

In some instances, a doctor may request a cardiopulmonary test, to determine if the curve is affecting the performance of the heart and lungs.

Scoliosis Surgery
A spine that has been instrumented with rods and screws to reduce a scoliosis curve

How is AIS Treated?

A patient’s treatment plan will be based on the severity of his or her curve.


Small curves may never develop into a serious problem. If a small curve of less than twenty degrees is detected, the doctor may choose to watch the curve in the coming months to see if it progresses.  If it doesn’t progress, it is unlikely that further treatment will be necessary.


In curves of 20-40 degrees, the doctor may prescribe that the patient wear a special brace.  The brace will fit over the patient’s torso, and can be worn under loose fitting clothes.  Some curves respond well to bracing (especially if the patient is still growing), while other curves continue to progress.


If bracing does not slow the progression of a curve, or if the curve has already progressed to a severe degree, surgery may be recommended.

The surgical techniques used to correct scoliosis have advanced remarkably in the last 20 years. The surgeon will seek to reduce the curve by using specially designed rods, screws and hooks that will be attached to your spine during surgery.  Surgery can reduce the curve, re-balance the spine, and reduce the likelihood of the curve progressing in the coming years.

Whether you are just starting to wonder if you or a loved one has AIS, or if you have a severe curve, you can be assured that Dr. Rahman and his team are superbly trained and highly experienced to give you the very best care.

Read About One of Dr. Rahman'sAIS CASES