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What is scoliosis?

Scoliosis is a spinal deformity that causes an abnormal curvature of the spine. A normal spine appears straight when viewed from behind, whereas a spine affected by scoliosis shows a lateral curvature, giving the appearance that the person is leaning to one side. The spine will often be shaped like an “S” or a “C.” The curvature must be 10 degrees or greater to be considered scoliosis.

Doctors use different terms to describe the different curvatures of the spine affected by scoliosis:

  • Dextroscoliosis—The spine curves to the right. This deformity usually occurs in the middle to upper section of the back (thoracic spine). This is the most common type of curve and can occur on its own to form a “C” shape, or with another curve to form an “S” shape.
  • Levoscoliosis—Spinal curve is to the left, typically occurring in the lower section of the spine (lumbar). In rare instances when this curve occurs in the thoracic spine, it may be the result of a spinal cord tumor or other spinal abnormalities.

Types of scoliosis

Nonstructural scoliosis

The spine is structurally normal and the curve is only temporary. The condition can be corrected once the underlying cause is identified and treated.

Structural scoliosis

The spine has a fixed and more permanent curve. This condition is usually the result of a birth defect, infection, disease or injury.

Idiopathic scoliosis

Idiopathic scoliosis refers to the 80 to 85 percent of scoliosis cases in which the cause is unknown. It occurs in adolescents between the ages of 10 and 18, and the majority of people afflicted with idiopathic scoliosis are adolescent girls.

 Idiopathic scoliosis is divided into three categories, depending on age range:

  • Infantile idiopathic scoliosis—Affects children under 3 years of age.
  • Juvenile idiopathic scoliosis —Affects children ages 3 to 10.
  • Adolescent idiopathic scoliosis (AIS) – Affects children 10 years of age and older. It's the most common type of scoliosis with an unknown cause. This condition is very likely to run in families.

Adult degenerative scoliosis

There can be confusion about idiopathic scoliosis and adult degenerative scoliosis. The most profound difference between these two types of scoliosis is that there is no known cause for idiopathic scoliosis, while there is a very distinct cause for adult degenerative scoliosis. Adult degenerative scoliosis usually affects people over the age of 65 and is a direct result of the degeneration of the facet joints in the spine.

Patients who suffer from idiopathic scoliosis rarely feel pain from the condition. Those suffering from adult degenerative scoliosis often feel pain caused by the deterioration of the facet joints. The abnormal curvature itself is not the cause for pain; the deterioration of the discs and facets resulting in arthritic changes of the spine causes most of it.

It is important not to confuse adult scoliosis with adult degenerative scoliosis. Adult scoliosis refers to abnormal curvature of the spine in patients over the age of 18. Sometimes, this can be a result of untreated and progressive childhood scoliosis or scoliosis that formed during adulthood.

Symptoms

Some physicians define scoliosis as a spinal curvature of 10 degrees or more. This small amount of curvature is not usually visible to the untrained eye. More obvious symptoms can include:

  • Gradual pain—Pain in different areas of the back, depending on the area affected by scoliosis, that comes on gradually and increases with activity.
  • Pain in the morning—Pain is worse upon waking, but eases once you are up and moving around. The pain increases later in the day, especially after a significant increase in activity.
  • Less pain when sitting—Pain is worse when you are standing or walking, because there is more pressure on the deteriorating facet joints. Sitting takes the weight and stress off the affected joints.
  • Leg pain—Feeling pain in one or both of your legs is a common symptom of adult degenerative scoliosis. When the facet joints are irritated, they become enlarged and can constrict the lumbar spinal canal, resulting in spinal stenosis or narrowing of the spinal canal and causing the leg symptoms. This constriction increases when you stand or walk. Sitting can relieve the constriction and pain.
  • Spinal instability
  • Rounded back and abnormal posture
  • Stiffness in the spine
  • Nerve damage
  • Heart and lung problems
  • Difficulty breathing

Idiopathic scoliosis usually does not cause pain or neurological symptoms in its early stages. In the beginning of the disease there is no pressure put on the internal organs by the curvature of the spine, so symptoms such as shortness of breath are usually not present.

Most patients with AIS do not have pain or any other symptoms. Symptoms of severe back or leg pain, numbness or weakness of the legs, and incontinence are generally not associated with AIS, and their presence should alert the physician to look for other causes of the scoliosis.

Adolescent idiopathic scoliosis symptoms are not limited to the physical; psychological effects and negative self-image tend to go along with a progression of the disease as well. This is particularly true in progressive cases, where the curvature of the spine is more severe and visible to an observer. This can affect the way that patients view themselves and thus result in negative associations with their own body image and lack of confidence.

Causes

The majority (85 percent) of all scoliosis cases are classified as idiopathic scoliosis, meaning they have no known cause. The remaining 15 percent of scoliosis cases are linked to causes such as:

  • Neuromuscular conditions—Cerebral palsy or muscular dystrophy can possibly lead to scoliosis.
  • Birth defects—During fetal development, either the bones of the spine fail to separate from one another or they do not form completely.
  • Arthritis—Scoliosis caused by arthritis is a degenerative form of the condition and usually occurs only in older adults.
  • Spinal conditions—Conditions that affect the spine and can lead to scoliosis can include osteoporosis, vertebral compression fractures, disc degeneration and spondylosis.
  • Injury – Trauma to the spine can cause scoliosis.

How is it diagnosed?

For scoliosis to be diagnosed, there must be at least 10 degrees of fixed lateral curvature of the spine. This is a measurement made on an X-ray.

Treatment options

Treatments for scoliosis depend upon the severity of the condition and range from nonsurgical treatments such as pain medications, observation and bracing to more invasive treatments like spinal fusion surgery. Three to five of every 1,000 children will develop some form of spinal curve severe enough to require treatment.

The most common treatments for adult degenerative scoliosis are nonsurgical approaches such as anti-inflammatory and pain medicines, therapy and exercise. Corrective surgery is rarely performed but can be quite complex, depending on your symptoms.

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