Simply stated, scoliosis is a lateral (or sideways) curvature of the spine measuring at least 10 degrees. This differs from kyphosis, which is a backwards curve, and lordosis, which is a frontward curve of the spine. In our body it is normal to have a lordosis in the neck (cervical) and lower (lumbar) spine, and a kyphosis in the mid (thoracic) spine. It is not normal to have a scoliosis in any part of the spine and therefore it is important that if one exists that it be found.

There are three main types of scoliosis:

Congenital Scoliosis

The congenital type implies that it is a curve that we are born with but actually the curve may not be something that can be detected until growth of the child. These curves are caused by either a failure of the spinal vertebra to form correctly or separate correctly. In those that fail to form normally, the vertebra are not square shaped but can be triangular in nature, which can cause a scoliosis. In those that fail to separate correctly, a bar can result on one side of the spine, also causing a curve because one side of the spine has a bar instead of normal growth plates. Children with congenital scoliosis often have other congenital anomalies (kidneys, heart, cleft palate) that need to be identified. These curves often progress and require treatment. Bracing is rarely helpful and surgery is often necessary to stop the progression of the curve.

Neuromuscular Scoliosis

The neuromuscular type of scoliosis is found associated with many neurological diseases. Most commonly it is seen in spina bifida, cerebral palsy, and muscular dystrophy. In this type of scoliosis, the vertebra are normal in shape, but because of the abnormal nerves supplying the vertebra, a curve often develops. The curves in these diseases often involve the entire thoracic and lumbar spine. Most of the children with these curves are not walkers, and therefore need treatment when the curve interferes with sitting. These curves also tend to be progressive and can be treated with bracing, wheelchair accommodations, and oftentimes surgery.

Idiopathic Scoliosis

Idiopathic scoliosis is the most common type of scoliosis, with approximately 1 per 100 people having a curve of at least 10 degrees. It is called "idiopathic" because no one is certain as to the reason why these curves occur, we just do not know. However, there are many theories about the origins of these curves including abnormalities in growth hormones, in the ligaments and discs of the spine, in the muscles and nerves of the spine, and in genetics. If these curves are allowed to progress, they begin to affect the function of the lungs when the curves reach 60 degrees. When the curves reach 90 degrees, the lung function worsens and can eventually lead to heart failure and cause death. There is evidence that in people with large curves (more than 40-50 degrees), there is an increased amount of back pain and a decrease in self image compared to people without curves. If a curve can be kept to less than 45 degrees when the child is finished growing there is an excellent chance that the curve will not progress to the point where problems will occur later in life.

There are three types of idiopathic scoliosis depending upon when in childhood they occur: infantile (age 0-3), juvenile (age 3-10), adolescent (age 10 to skeletal maturity). Currently, school screening is performed to try to detect scoliosis before the curve is too large. Children bend forward and an observer looks at the back for a prominence of the spine or an asymmetry of the neck, shoulders, flank, and pelvis. Some schools use a scoliometer, which is a device to measure the rotation of the back when the child is bent over. A measurement of 5 to 7 degrees on the scoliometer typically indicates a curve that can be seen on X-ray. The child is usually sent to a physician's office once they fail school screening.

Once in the doctor's office, a thorough history and physical are carried out. As part of the exam, the physician typically asks about family history, history of back or leg pain, maturity characteristics, and menstrual history (the last two help determine how much growth the patient has left which is important in deciding who needs treatment). On exam the physician looks at the magnitude of the curve and flexibility on forward and side bending, the location of the head over the center of the pelvis, and performs a full neurologic exam. X-rays are taken if the physician feels the physical exam suggests that there is a curve. The X-ray is examined for the magnitude of the curve, level of skeletal maturity, the direction of the curve (to the right or left) and whether the bones of the spine are normal or not. If there is an abnormality of the neurologic examination, if the curve points to the left side, or if the child is under age 10, an MRI test may be ordered because there is an increased likelihood that these patients and their curves are associated with abnormalities of the spinal cord such as cysts, a split or tethered spinal cord, or tumors.

As discussed earlier, 1% of the population (100 out of 1000) has a curve that measures 10 degrees, but only 1 patient in 1000 has a curve that reaches 40 degrees. If we treated every patient with a 10 degree curve, 99 would be treated unnecessarily. So whom should we treat? Based on studies of patients with idiopathic scoliosis who did not have any treatment we know that the larger the curve at diagnosis, the greater the chance of progression. (see table) We also know that the younger the child at the time of diagnosis, the greater the chance of progression of the curve. (see table) Although school screening finds boys and girls equally, those requiring treatment are mostly girls.


Percent chance of progression: (curve size vs. age)

10-12 years old

13-15 years old

16 or > years old

< 19 degrees




20-29 degrees




30-59 degrees




> 60 degrees




Based on the data above as well as other studies on curve progression, there are two main treatment approaches: nonoperative and operative. The nonoperative approach consists of either observation or bracing. If a curve measures less than 10 degrees on X-ray it is not very likely to progress. These children can be followed with repeated school screening, exams by the family physician and if things appear to be worsening the child can be sent to an orthopedist for further evaluation or X-rays. Some orthopedists will follow these children in their office with clinical exams and scoliometer readings yearly until growth slows or ceases, only taking X-rays if the measurements worsen.

If a child has a curve of 10 degrees or more, they should be followed by clinical and X-ray exam every 3 to 6 months to check for progression. If a curve progresses to between 25-30 degrees in either a child being followed or an immature child upon presentation, or if a child presents with a curve between 30-40 degrees, then bracing is recommended.

There are three main types of braces used by orthopedists. For curves that reach into the upper thoracic spine, the "Milwaukee" brace is used for it is able to control curves higher up in the spine. For curves in the lower thoracic spine or lumbar spine a "TLSO" type of brace can be used. Various names are associated with this type of brace such as a Boston or Wilmington brace, known for the geographical origin of the brace. The "TLSO" and "Milwaukee" braces are typically prescribed to be worn from 16 to 23 hours per day. The third type of brace is worn only at night and is used for lower thoracic and lumbar curves. It is called the "Charleston Bending" brace. All of these braces push against the curve to try and stop progression, however, the "Charleston" overcorrects the curve and exerts more force than the other two and therefore can only be worn at night. Preliminary studies of the "Charleston" show promise but it is not as well tested as the other two braces. In a skeletally immature child a brace can reduce the chance of progression in a 20-29 degree curve from 70 percent to 30 percent.

Other types of nonoperative treatment have been tried over the years but only bracing has been proven to statistically reduce the chance of progression from that of observation. These treatments include exercise, electrical stimulation, diet, manipulation, biofeedback, and others. Both exercise and electrical stimulation have been studied scientifically and have not shown an improvement compared to curve observation. There are no studies showing that the other methods are effective.

If a child presents with a curve of 45-50 degrees, studies have shown that a brace does not stop the curve from progressing further. In addition, if a curve progresses to that level while undergoing brace treatment, it is considered a treatment failure. In both situations something more that bracing needs to be done to stop curve progression. The only other alternative available is surgery.

The goal of surgery is to fuse the segments of the spine that are involved in the curve to stop them from producing further curve growth. Today this is commonly done by surgically removing the joints in the spine and placing bone graft into the joints to make them fuse. Metal is placed to hold the spine in position to allow it to fuse as quickly as possible and also correct the curve as much as possible. By using these rods, hooks, and screws, most patients no longer have to wear body casts or braces after surgery. The surgery can be performed through the patient's back, front, or both depending on the size, flexibility, and location of the curve, and the patient's age. Generally, smaller and more flexible curves are approached through the back, while bigger less flexible curves require both a front and back approach. A front only approach is used in some lumbar curves to minimize the number of vertebra that need to be fused. Some centers are using techniques of arthroscopic surgery in the thorax and abdomen to perform the front approach without having to make large incisions.