ByFrank Pessler, MD, PhD, Helmholtz Centre for Infection Research
Reviewed/Revised Nov 2022

Scoliosis is abnormal curvature of the spine.

  • Scoliosis can be present at birth or can develop during adolescence.

  • Mild forms may cause only mild discomfort, but more severe forms can cause chronic pain or affect internal organs.

  • The diagnosis is based on an examination and x-rays.

  • Not all forms of scoliosis worsen, but those that do must be treated as soon as possible to prevent a severe deformity.

  • Braces or surgery may be needed to straighten the spine.

(See also Overview of Bone Disorders in Children.)

Scoliosis is relatively common and occurs in 2 to 4% of children aged 10 to 16 years. Boys and girls are affected equally. However, in girls, scoliosis is 10 times more likely to progress and require bracing or surgery.

Scoliosis may result from hereditary causes, birth defects, or injuries or develop later in life, most often in early adolescence. Usually, the cause cannot be identified (called idiopathic scoliosis).

The spine usually bulges toward the right when the curvature is in the upper back and to the left when it is in the lower back. The result is that the right shoulder is usually higher than the left. One hip may be higher than the other. The chest may not be symmetrical. Scoliosis often develops in children with kyphosis. The combination is called kyphoscoliosis.

Idiopathic Scoliosis
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This photo shows an adolescent girl with severe scoliosis (curvature of the spine).

Symptoms of Scoliosis

Mild scoliosis usually causes no symptoms. Sometimes the back becomes sore or stiff after the child sits or stands for a long period of time. Mild or more severe pain may eventually follow.

Mild scoliosis may be discovered during a routine physical examination. A parent, teacher, or doctor may suspect scoliosis when one of the child’s shoulders seems higher than the other or when the child’s clothes do not hang straight.

Diagnosis of Scoliosis

  • X-rays

To diagnose scoliosis, a doctor asks the child to bend forward and views the spine from behind because the abnormal spinal curve can be seen more easily in this position.

Scoliosis: A Curved Spine

X-rays show the precise angles of curvature. The amount of curvature is defined as the angle between two lines drawn on an x-ray of the spine. The angle is termed the Cobb angle. One line extends from the top of the most tilted upper vertebra and the other line extends from the bottom of the most tilted lower vertebra.

The Cobb Angle

In the Cobb method, two lines are drawn on an x-ray of the spine. One line extends from the top of the most tilted upper vertebra and the other line extends from the bottom of the most tilted lower vertebra. The angle formed by these lines is the Cobb angle. (The convex side is where the spine curves outwards. The concave side is where the spine curves inwards.)

If doctors think scoliosis may worsen, they may examine the child several times a year. Special devices may be used to measure the curve of the spine more precisely.

Prognosis for Scoliosis

A number of factors contribute to the likelihood of scoliosis worsening. The more severe the curve, the greater the likelihood of it worsening, and curves tend to worsen in the early stages of puberty when growth is accelerated. Likewise, the more symptoms that develop, the greater the likelihood that scoliosis will worsen. Worsening scoliosis may eventually cause permanent problems, such as noticeable deformities or chronic pain. Severe scoliosis may even affect internal organs—for example, deforming and damaging the lungs. Sometimes scoliosis can worsen even if symptoms have not developed.

In most children who have scoliosis, the curvature does not progress further but rather remains small. However, it needs to be monitored by a doctor regularly. Scoliosis that causes symptoms, is worsening, or is severe may need to be treated. The earlier treatment is begun, the better the chance of preventing a severe deformity.

Treatment of Scoliosis

  • A brace and physical therapy

  • Sometimes surgery

A brace or object fashioned to hold the spine (orthosis) may be worn to keep the spine straight. Children also undergo physical therapy to prevent further deformity.

In the most severe cases, the vertebrae need to be bonded together surgically (spinal fusion). A metal rod may be inserted during surgery to keep the spine straight until the vertebrae have bonded permanently. Less than 10% of children need major treatment.

Braces for Scoliosis
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To treat scoliosis, a brace may be worn to keep the spine straight.

Scoliosis and its treatment often interfere with an adolescent’s self-image and self-esteem. Counseling or psychotherapy may be needed.

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