Scoliosis is the most common deformity of the spine. Other common spinal deformities include kyphosis and lordosis, however these deformities are much less common. The diagnosis of scoliosis is made when there are two abnormalities of the spine:
A lateral curvature of the spine means that the vertebral column bends from side-to-side. If looking at an individual from behind while they bend to touch their toes, there is an S-shaped curvature of the spine. A slight degree of lateral curvature of the spine is not necessarily abnormal. Lateral curvatures of the spine less than 10 degrees are within the limits of normal.
The rotational deformity is usually subtle, but is always present in a true scoliosis deformity. The rotational aspect of scoliosis causes a twisting deformity of the vertebral bodies.
Causes of Scoliosis
In order to answer this you must first understand that there are several categories into which scoliosis as a general syndrome is separated. The most common form of scoliosis (over 80% of cases) is called "idiopathic scoliosis." The word idiopathic simply means that the cause is not known. Idiopathic scoliosis is further classified by age group. The following are the four types of idiopathic scoliosis:
- Infantile (birth to 3 years)
- Juvenile (3 years to puberty)
- Adolescent (at or just after puberty)
- Adult (over age 20)
Congenital scoliosis is the result of an abnormality of the development of the vertebrae. When the bones of the spine fail to develop normally, a scoliosis deformity can result. Also, some specific congenital syndromes can include a scoliosis deformity. These syndromes include Marfan syndrome, Ehlers-Danlos syndrome, Osteochondrodystrophy (dwarfism), and others. These are all examples of structural scoliosis; this means that the spine has a problem within the vertebral column that is causing the abnormal curvature.
Another category of scoliosis is non-structural, or functional, scoliosis. This occurs when there is a problem with another part of the body that is causing a curve in the spine. For example, a discrepancy in leg length can cause the spine to curve to one side. Muscle spasms and inflammation may also cause this problem. When a scoliosis is classified as non-structural, treatment is aimed at the underlying problem, not the spine itself.