Adolescent Idiopathic Scoliosis

The word “idiopathic” defines the cause of a disease or condition as unknown. Adolescent idiopathic scoliosis affects children between 10 and 18 years old and is more common in girls than boys. In fact, girls are treated 10 times more often. There are many theories as to why this type of scoliosis develops, however, the root cause of the condition has yet to be discovered. Some of the theories include:

Genetics – Scoliosis appears to run in certain families, therefore, the condition may be hereditary. Significant research is ongoing in the field of genetics.

Growth – Curves progress rapidly during growth spurts, perhaps showing a tie to hormonal causes

Structural and biomechanical changes – Some studies have shown increased muscular activity around the spinal curves. Differences in leg lengths have also been noted in adolescents with idiopathic scoliosis. There is no clear evidence that this type of change causes scoliosis; it may simply be a secondary result.

Central nervous system changes – Because some forms of scoliosis are associated with central nervous system disorders, a lot of research has been focused on this topic. Such disorders have not yet been proven and the exact cause of idiopathic scoliosis still remains unidentified.

Equilibrium and postural mechanisms – Idiopathic scoliosis could be related to factors that affect body alignment. If a child has problems with posture, balance and body symmetry, it could affect the way the spine is positioned. If the problems are chronic, it may disrupt the way the spine and muscles develop

Likelihood of Progression

Once scoliosis is diagnosed, concern may arise whether the curves will continue to grow larger. There is no absolute way to tell, however, this much is known:

  • Curves in the thoracic spine are more likely to progress than lumbar curves
  • The likelihood of progression is linked to the size of the curve. Larger curves are more likely to get bigger
  • If the curves start at a young age or before a girl begins her period, they are more likely to progress
  • The higher the child’s Risser sign is at diagnosis, the less chance there is of progression. The Risser sign also measures skeletal maturity. (It is based on a zero to five scale, with five being full skeletal maturity.) This measure is based on the iliac apophysis, which is layer of cartilage on the flared part of the hip bone that turns to bone with age and maturity.


In many cases of adolescent scoliosis, the child will not even notice the problem. Because the majority of scoliosis patients do not suffer any physical pain from this disorder, it is often not discovered until the curves have progressed to become more obvious. In fact, if the child is suffering from severe back pain, a diagnosis other than idiopathic scoliosis must be considered.

Though the spine may curve sideways, in minor cases the curves are not obvious until the person bends over. Many schools currently screen young students for scoliosis. As a result, referrals often come from school health workers. Frequently, parents or physical education instructors notice the first signs of scoliosis in a child. Signs of scoliosis may include the following abnormalities in appearance:

  • One shoulder or hip may be higher than the other
  • One shoulder blade may be higher and stick out farther than the other
  • These deformities are more noticeable when bending over
  • A “rib hump” may occur, which is a hump on the back that sticks up when bending the spine forward. This occurs because the spine and ribs also rotate as the curve develops
  • One arm hangs longer than the other because of a tilt in the upper body
  • The waist may appear asymmetric

Treatment Options

The treatment chosen for an adolescent with idiopathic scoliosis will vary depending upon the severity of the curve, the age of the patient and how far along the child is in skeletal maturity.

Conservative Treatment

Monitoring – If the patient’s curve is minor (less than 15-20 degrees), the doctor will likely choose to monitor the curve for progression. The patient will normally have X-rays taken every four to six months during rapid growth years and then once a year.

Physical Therapy and Exercise – Adolescents with scoliosis may work with a physical therapist. A well-rounded rehabilitation program assists in calming pain and inflammation, improving mobility and strength and helping with daily activities. Adolescents with idiopathic scoliosis should be encouraged to continue their normal activities, including sports.

Exercise has not proven helpful for changing the curves of scoliosis. However, it can be helpful in maintaining flexibility, especially in the hamstrings and low back. Therapy sessions may be scheduled each week for four to six weeks.

The goals of physical therapy are to help:

  • Improve back posture
  • Foster aerobic fitness
  • Maximize range of motion and strength
  • Clarify ways to manage the symptoms of scoliosis

Bracing – Bracing is usually considered with curves between 25 and 40 degrees. The curve is likely to get bigger if the patient is still growing. It is important that the patient wear the brace daily for the number of hours prescribed by the doctor. Scoliosis often affects more than one area of the spine. A brace can be used to support all the curved areas that need to be protected from progression.

Sometimes an adolescent might feel self-conscious about wearing a brace. Though the brace can help the curve from getting worse, it may take some time for the patient (and caregiver) to get used to it. Adults tend to be less concerned about what their peers think, but adolescence is a time when appearance is often of great importance. Listen to the child’s concerns and look for ways to help overcome feelings about appearance.

Surgical Treatment

Surgery is generally only considered in patients who have continual pain, difficulty breathing, significant disfigurement, or a steadily worsening curve angle. After skeletal maturity occurs, curves that are less than 30 degrees tend not to progress and, therefore, do not require surgery. Curves above 100 degrees are rare, however, they can be life threatening if the spine twists the body enough to put pressure on the heart and lungs.

If a curve is 45 degrees or more, surgery is more likely to be considered. The main surgery for scoliosis is spinal fusion with instrumentation. Most surgical procedures will use rods in order to help straighten the spine.

A spinal surgeon may use a posterior approach, which involves going into the spine through the back, or an anterior approach, which is performed from the front or side. The operation can be performed from both the front and the back (a combined approach). The choice depends upon the flexibility of the spine, the location and degree of the curve and whether there is pressure on any of the nerve roots. The age of the patient is a factor in deciding which type of surgery is used. Patients whose spines are immature are more likely to require combined anterior and posterior fusion (see below).

Anterior Instrumentation – An incision is made in the chest or flank and the intervertebral discs are removed in the area of the curve to make it flexible. Screws can be placed in the vertebrae and then connected by a metal rod. A bone graft is put in place of the discs that were removed so that the vertebra sitting next to each other will fuse together. The screws attaching the metal rod are tightened down, straightening the curve.

Posterior Instrumentation – This approach is done through the back. Anchors are attached to the spine in the form of hooks, screws, or wires. These anchors are attached to spinal rods that straighten the spine. Bone grafting is done to fuse all instrumented vertebrae.

Combined Anterior/Posterior Approach – This surgery is actually two operations-one through the front and the other through the back. The two operations may be staged on separate days or as part of one longer surgery. Staged procedures require one to two additional days in the hospital compared to a single surgical procedure.

Other Considerations

Even though it is recommended to them, a patient may choose not to have surgery because of the risks. There are also risks of leaving large curves untreated:

  • Increased back pain – Patients with untreated large curves can suffer from daily back pain.
  • Reduced respiratory function – Large curves lead to deformities that can lower the space for the body’s vital organs, such as the lungs and heart. The reduction in space can compromise the ability to breathe and for the heart to function properly. In curves of 100 degrees or more, the affects can be life threatening.