Scoliosis is not a disease, rather the word is a term used to describe any abnormal, sideways or lateral curvature of the spine. Viewed from the back, a typical spine is straight. The spine curves to either side as a single curve shaped like the letter C or “c-shaped scoliosis” or the spine has two curves and is shaped like the letter S or “s-shaped scoliosis”… rarely the curve can be a triple.
Curves are classified by many different components such as their location in the spine.They can occur in the upper back (cervical spine scoliosis), in the middle back (thoracic spine scoliosis) and in the lower back (lumbar spine scoliosis) in various combinations. Thoracolumbar scoliosis is curvature that includes vertebrae in both the lower thoracic and upper lumbar portion of the spine. Curves can also be defined as left thoracic or right thoracic.
Dextroscoliosis is a spinal curve to the right (“dextro” means right). Usually occurring in the thoracic spine, this is the most common type of curve. It can occur on its own (forming a c-curve) or with another curve bending the opposite way in the lower spine (forming a s-curve). The reason dextro is most common is that the body instinctively avoids the heart which is located to the left of the midline of the torso.
Levoscoliosis is a spinal curve to the left (“levo” means left). Common in the lumbar spine, the rare occurrence of levoscoliosis in the thoracic spine indicates a higher probability that the scoliosis may be secondary to a some kind of pathology such as a spinal cord tumor or chiari syndrome.
Kyphosis is a curve seen from the side in which the spine is bent forward. There is a normal kyphosis in the middle (thoracic) spine. Kyphoscoliosis is the abnormal curvature of the spine, both sideways and towards the upper back. Lordosis is a curve seen from the side in which the spine is bent backward. There is a normal lordosis in the upper (cervical) spine and the lower (lumbar) spine.
IDIOPATHIC SCOLIOSIS CLASSIFICATIONS
Idiopathic scoliosis occurs in approximately 4% the population. The term idiopathic means a condition or disease with no known cause. Idiopathic scoliosis is by far the most common cause of scoliosis. Idiopathic scoliosis rarely causes pain. Once scoliosis is detected it should be closely monitored by a scoliosis professional. That expert will initiate a proactive plan to ensure the curve does not progress, and if possible will be reduced and stabilized.
Idiopathic scoliosis is divided into three subgroups according to age: infantile (0-3 years), juvenile (4-10 years), and adolescent (11- maturity)
Infantile Idiopathic Scoliosis
Juvenile Idiopathic Scoliosis
Juvenile onset scoliosis is defined as spinal curves diagnosed between ages 3-10. It less common than adolescent scoliosis but still makes up one-fifth of scoliosis cases. Juvenile idiopathic scoliosis is very different from infantile and adolescent idiopathic scoliosis. Accurate diagnosis is essential.
Adolescent Idiopathic Scoliosis
Adolescent idiopathic scoliosis occurs in children age 10 to 18 years old, and comprises approximately 80% of all cases of idiopathic scoliosis. This age range is when rapid growth typically occurs, which is why the detection of a curve at this stage should be monitored closely for progression as the child’s skeleton develops.
Adult Idiopathic Scoliosis
Once skeletal maturity is reached, a patient with adolescent idiopathic scoliosis is now said to have adult idiopathic scoliosis. A patient with Adult Idiopathic Scoliosis will still benefit from treatment for progression, but pain is a much more common indication for treatment. Normal degenerative changes of the spine may be accelerated by curvature and the patient may be at higher risk for skeletal pain or extremity pain due to nerve compression.
Not to be confused with adult idiopathic scoliosis, Adult Scoliosis or Adult Onset Scoliosis is a Degenerative scoliosis, or a side-to-side curvature of the spine caused by degeneration of the facet joints. Degenerative scoliosis occurs in older adults, most frequently in people over age 65 . Typically a C-shaped curve forms in the lumbar spine. It can occur due to arthritis in the spine, Spondylosis. Weakening of the normal ligaments and other soft tissues of the spine combined with abnormal bone spurs can lead to an abnormal curvature of the spine. The spine can also be affected by osteoporosis, vertebral compression fractures, and disc degeneration. Other potential causes include spine tumors such as osteoid osteoma, a benign tumor that can occur in the spine and cause pain. This pain causes people to lean to one side to reduce pressure on the tumor causing spinal deformity. Degenerative scoliosis is the most common form of scoliosis in adults.
Other types of Scoliosis Classifications
Nonstructural (Functional) scoliosis: a curve in the spine, without rotation, that is reversible because it is caused by a condition such as: pain or a muscle spasm or a difference in leg length. In this type of scoliosis the spine is normal, but an abnormal curve develops because of a problem somewhere else in the body.
Neuromuscular scoliosis: there is a problem when the bones of the spine are formed. Either the bones of the spine fail to form completely or they fail to separate from each other during fetal development. This type of scoliosis develops in people with other disorders, (i.e. birth defects, muscular dystrophy, cerebral palsy, or Marfan’s disease. People with these conditions often develop a long C-shaped curve and their muscles are unable to hold their spine straight. If the curve is present at birth, it is called Congenital Scoliosis This type of scoliosis is often much more severe and needs more aggressive treatment than other forms of scoliosis.
Compensatory scoliosis: is a spinal curve in the coronal plane which disappears when the patient sits. It may be caused by either a short leg or a pelvic tilt due to abduction or adduction contracture of the hip.
straighten significantly on side-bending and function to produce spinal balance. There is no underlying structural abnormality.
The location of the structural curve determines the classification of the scoliosis e.g. a structural curve in the thoracic spine with a lumbar compensatory curve is called thoracic adolescent idiopathic scoliosis. Single curves, curves whose apex is at T12 or 11 may be defined as a Thoracolumbar curve , and curves with apices at 12 or 13 are defined as lumbar curves. Structural curves in both the thoracic and lumbar spine are called double major curves. The exact definition of the curve has implications for determining scoliosis progression and scoliosis treatment.
This is an explanation of just a few basic terms used to classify scoliosis. If it appears complicated, it is. If it doesn’t, don’t make the mistake of assuming you have enough understanding to self-diagnose. There are even more complicated classifications for scoliosis such as the King and Lenke Classification systems. It’s always best to consult your physician with any questions you may have about your scoliosis diagnosis.
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