SCOLIOSIS IN ADOLESCENCE
Most humans have 7 cervical vertebral bodies or vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae, for a total of 24 in the average spinal column.
The cervical vertebrae are the most agile, and when bowing forward into the thyroid area of the neck, create a sagging or “lordosis.” When the thoracic vertebrae bow out from the chest, called a “kyphosis,” while the lumbar vertebrae bow in toward the abdomen, as a lordosis.
The natural curves of the spine lie in the sagital plane, which divides the left side of the body from the right. The spinal vertebral bodies articulate in most cases with adjacent vertebrae. This allows a range of rotation and forward-to back and side-to-side movement (See Photo).
Scoliosis is an asymmetrical curvature of the spinal column, wherein the column leaves the sagital plane, usually involving convexity of the thoracic spine toward the right shoulder, and convexity of the lumbar spine toward the left kidney.
In the thoracic region of the scoliotic spine, rotation occurs, bringing the ribs of the right chest rise up from the back, allowing measurement of this incline with an inclinometer.
An audiovisual depiction of idiopathic scoliosis is available at the NuVasive website,http://www.nuvasive.com/. Go to “Speed of Innovation” and drag down the box under PATIENT SOLUTIONS. Click “Degenerative Scoliosis,” then click on “Play with Animation.”
Impaired bony growth in a segment of vertebral bodies during the growth phase of youth may lead to scoliosis in adolescence.
Most cases of scoliosis of adolescence are “idiopathic,” meaning the cause of the disease is unknown. Over 90% of cases of idiopathic scoliosis occurring in adolescence exhibit a thoracic spine bowed toward the right shoulder.
These deformities cause a rotation to occur in the spine, bringing the right ribs up and away from the pectoral region, producing a slant or incline across the back, the severity of which can be measured with a device known as an inclinometer.
Measurement is accomplished according to the following algorithm: With the subject in Adams’s position (standing bent over 90o at the waist, arms extended, palms pressed together, pointing at the feet) an inclinometer is laid across the slanting area of the thoracic spine. If an incline equal to or greater than 7ois found, a standing xray of the thoracic to lower lumbar spine is ordered.
Interpretation of the standing x-ray leads to clinical intervention based on the Cobb angle* as measured on the x-ray.
For adolescents with scoliosis undergoing evaluation by a primary care physician (PCP), the following rules apply for testing, referral, and follow-up of scoliosis:
In a prepubertal girl or boy with a Cobb angle between 10o and 14o and no red flagsr present, only a repeat history and algorithm at follow-up in one year is needed.1
In a prepubertal girl or boy with a Cobb angle of 15o to 19o, follow-up is needed in 3-6 months, and a repeat history and algorithm is run. Referral to a specialist is made if there is an increase in the Cobb angle of >5o.
If the Cobb angle is >20o in a prepubertal boy or girl, referral to a specialist is needed.
For pubertal girl or boy age 12 to o to 14o, a repeat history and algorithm is needed at follow-up in 1 yr.
For a pubertal boy or girl with a Cobb angle of 15 to 19 degrees, follow-up in 3 mos with repeat history and algorithm is needed. Refer if the Cobb angle increases >5 degrees.
In a pubertal boy or girl in whom the Cobb angle is 20-24 degrees, follow-up in 3 months is needed with xray, and refer if the Cobb angle increases >5 degrees.
In a pubertal boy or girl with a Cobb angle >25 degrees, refer.
For a post-pubertal boy or girl, age 14 to
A post pubertal boy or girl, aged 14 to >5 degrees.
For a post pubertal girl or boy age 14 to >30 degrees.
For a girl aged 2 years after menarche or boy age 16 >5 degrees. If initial Cobb angle >30o refer to spine specialist.
Most cases of idiopathic scoliosis occurring in adolescents have a favorable prognosis, and treatment is readily available in most cases where specialty intervention is necessary.
*The Cobb angle of measurement of scoliosis is defined as the angle between a line parallel to the superior vertebral body and a line at the inferior vertebral body of the curve.
r Red flags are risk factors or precursors of a more ominous course in adolescent scoliosis and include significant pain, neurofibromatosis, connective tissue disease, left curvature, neurologic abnormalities, foot deformity, and/or excessive lordosis or kyphosis.
References:
[1] M. Timothy Hresko, M.D. Idiopathic Scoliosis in Adolescents N.Engl.J.Med 2013;368:834-41.
[2] www.nuvasive.com