Scoliosis is an abnormal curvature of the spine from side to side. It may also include an abnormal rotation of the spine. There are two basic types of scoliosis: idiopathic, which is the more common and accounts for 80–85 percent of cases; and scoliosis that is caused by a disease, injury, or temporary condition. Idiopathic means that the cause of the disorder is unknown.
The 15–20 percent of cases of scoliosis that do have causes are divided into two categories, structural and nonstructural (also called functional). A child with nonstructural or functional scoliosis has a spine that is structurally normal but looks curved at the moment because of a difference in leg length or muscle spasms. It can be treated by therapy for the underlying cause. Structural scoliosis is caused by certain neuromuscular diseases, including Marfan syndrome, muscular dystrophy, and polio; or by infectious diseases or tumors on the spinal column. In adults it may be caused by osteoporosis or compression fractures.
Scoliosis is an abnormal curvature of the spine from side to side and usually rotated inward or outward as well. It is best understood as a complex three-dimensional distortion of the spine's normal pattern. The normal human spine does have an S-shaped curve when viewed from the side; that is, the twenty-five vertebrae in the human spinal column are not arranged in a straight line from the neck to the tailbone but curve inward slightly in the neck region, outward in the chest area, and inward again in the lower back. When viewed from the center of the patient's back, however, the vertebrae should lie in a straight line. Any curvature of 10 degrees or more to the left or right is considered scoliosis.
The severity of scoliosis varies; some children do not require treatment at all and others do well simply having their growth and any changes in the spine monitored by their doctor. Still others require treatment, most often with either specially designed braces or surgery. Adults with scoliosis are more likely than children to have deformities severe enough to cause noticeable pain and difficulties with breathing.
Scoliosis can occur at any age, but most studies of it focus on children and adolescents, which are the age groups most commonly affected. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), between three and five out of every 1,000 children in the United States have scoliosis severe enough to require treatment. Scoliosis is most likely to affect children over the age of ten. Babies who are born with scoliosis are said to have congenital scoliosis.
In young children, scoliosis affects boys and girls equally; in adolescence, however, girls are twice as likely as boys to develop scoliosis. The curvature of the spine generally worsens during growth spurts.
Curves that face the right side of the child's body are more common than those that face left, and C-shaped curves are more common than S-shaped curves.
In adults, scoliosis may result from a condition that actually began in childhood and was not diagnosed or treated while the person was still growing. What may have started out as a slight or moderate curve in the spine may have become worse in the absence of treatment. In other cases, adult scoliosis results from osteoporosis or other disorders that affect an older person's bones and muscles.
Scoliosis may have a number of different causes.
- Abnormal development of the spine prior to birth. Most cases of congenital scoliosis are caused by either abnormally shaped vertebrae or fusion of the baby's ribs.
- Genetic factors. Although only one specific gene has been linked to scoliosis, there are likely to be others involved. The disorder is known to run in some families. A person with a family member who has scoliosis has a 20 percent greater chance of developing scoliosis themselves.
- Injury. Some cases of scoliosis are the result of injuries to a baby's spine during a difficult childbirth.
- Diseases that affect connective tissue, the muscles, or the skeleton. These include polio, Marfan syndrome, muscular dystrophy, or cerebral palsy.
- Tumors on the spinal column.
- Infectious diseases.
- Osteoporosis and other diseases that may weaken bones in older adults.
The symptoms of scoliosis vary in severity from child to child; some common symptoms include:
- Protruding shoulder blades or a hump near the rib cage (caused by rotation of the spine inward)
- Uneven development of the back muscles
- Uneven hip and shoulder levels
- Uneven development of the breasts in adolescent girls
- Fatigue or pain in the spine after long periods of sitting or standing
- Unequal distance between the arms and the body
- Head may be tilted off-center
- Tendency to walk with a rolling gait
In adults, scoliosis is more likely to be associated with the development of a hump in the upper back, breathing disorders, and pain.
Diagnosis of scoliosis begins with a family history as well as a history of the child's medical problems, birth defects (if any), and injuries that may have affected the spine. The doctor will also examine the child's skin for café-au-lait spots; these are brownish-white spots that indicate the scoliosis may be the result of a birth defect. If the patient is an adult, the doctor will look for evidence that the scoliosis is the result of a childhood problem that was never treated, or that it is due to an adult-onset disorder like osteoporosis.
The most common diagnostic test for scoliosis in adults as well as children is the Adam Forward Bending Test. The patient faces forward with feet straight ahead and palms inward against the sides of the body. With the knees locked, the patient slowly bends over at the waist and tries to touch the toes. The doctor then evaluates the spine for the appearance of straightness. An x ray may be taken to allow the doctor to measure the exact degree of abnormal curvature. X-ray photographs can also be used to measure the improvement in the spine during treatment.
Adult patients may be given a neurological examination as well as an x ray if their scoliosis is causing difficulties in bowel or bladder habits, general weakness, or unusual sensations in the arms or legs.
Many children are diagnosed with mild scoliosis as part of a school screening program and may not need special treatment. If the child's doctor thinks that he or she should be treated, the child will usually be referred to an orthopedic specialist.
Treatment of scoliosis is based on the degree of the curvature of the patient's spine; his or her age; whether the patient is likely to continue growing; and the type or cause of the scoliosis:
- Observation. If the child is still growing, has idiopathic scoliosis, and has a curvature of 25 degrees or less, the doctor will usually check the child's growth during an office visit every four to six months.
- Bracing. If the child has at least two years of growth left; is a girl who has not yet had her first period; has idiopathic scoliosis with a curve greater than 25–30 degrees; or has a curve that is getting noticeably worse, the doctor will recommend braces. A child who must wear a brace can, however, participate in a full range of school and social activities. If properly fitted, braces can prevent the need for surgery in 90 percent of cases.
- Surgery. Surgery may be needed when the child has stopped growing; has a curvature that is greater than 45 degrees; or has a curvature that is getting worse rapidly. Surgical treatment of scoliosis involves fusing several vertebrae together to correct the curvature and may require inserting metal rods next to the spine to reinforce the fusion.
Adult patients with scoliosis are usually treated with surgery either for pain control or to relieve pressure on the heart and lungs from the deformed spine.
Other forms of treatment for scoliosis that are not considered effective include dietary changes, vitamin supplements, exercise programs, chiropractic manipulation of the spine, and electrical stimulation.
Although physical exercise should not be used as a treatment to correct the curvature of the spine, it is an important part of overall health care for children with scoliosis. Regular exercise helps to keep the body fit and healthy, improves overall well-being, and reduces the risk of osteoporosis in girls and women.
The prognosis of scoliosis depends on the risk that the curvature of the patient's spine will progress (get worse). In general, the prognosis is better for smaller curves than for larger ones, and better for patients whose bones are mature than for those whose spines are still growing. In general, mild cases of scoliosis treated with bracing alone do very well. These patients do not usually have long-term health problems except for a slightly increased risk of pain in the lower back when they get older. People with surgically corrected idiopathic scoliosis also do very well and can lead active, healthy lives.
The prognosis of patients with scoliosis related to neuromuscular diseases like muscular dystrophy or cerebral palsy is determined by the outcome of their disease rather than by treatment for the scoliosis by itself.
Scoliosis cannot be prevented in the great majority of cases because its causes are still not fully understood.
Doctors expect that the number of cases of adult-onset scoliosis will increase in the years ahead because of the growing number of people over 65 in the general population. Earlier diagnosis and treatment of scoliosis in children, however, is lowering the need for surgery as a treatment for the disorder.
After the discovery in 2007 of the first gene linked to scoliosis, it is likely that researchers will identify other genes related to the condition. These discoveries in turn may shed light on the causes of idiopathic scoliosis and possibly lead to the development of new treatments.
SEE ALSO Cerebral palsy; Marfan syndrome; Muscular dystrophy; Osteoporosis; Polio
WORDS TO KNOW
Café-au-lait spots: Brownish-white birthmarks that appear as part of a nervous system disorder that can cause scoliosis in some children. Café au lait is the French expression for “coffee with milk” and describes the color of the spots.
Chiropractic: An approach to treatment of disease based on manipulation of the spinal column.
Congenital: Present at birth.
Gait: A person's habitual manner of walking.
Idiopathic: The medical term for a disorder whose cause is unknown.
Orthopedics (also spelled orthopaedics): The branch of medicine that deals with the prevention, diagnosis, and treatment of disorders of the skeleton and muscles.
Golden, Elizabeth. When Life Throws You a Curve: One Girl's Triumph over Scoliosis. Chandler, AZ: Five Star Publications, 2007.
Silverstein, Alvin, Virginia Silverstein, and Laurie Silverstein Nunn. Scoliosis. New York: Franklin Watts, 2002.
Washington University in St. Louis. “First Gene Linked to Scoliosis Identified.” ScienceDaily, June 15, 2007. Available online at http://www.sciencedaily.com/releases/2007/06/070614100445.htm (accessed June 12, 2008).
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National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Questions and Answers about Scoliosis in Children and Adolescents. Available online in PDF format at http://www.niams.nih.gov/Health_Info/Scoliosis/scoliosis_qa.pdf (accessed June 12, 2008).