Idiopathic adolescent scoliosis

Late onset idiopathic scoliosis affects children between 10 and 15 years of age, and predominantly, girls - 90% of cases - possibly associated with the more rapid female pubertal growth spurt. In general, the scoliosis is right sided convex (1)

• adolescent idiopathic scoliosis is present in 2 to 4 percent of children between 10 and 16 years of age (2)
  • defined as a lateral curvature of the spine greater than 10 degrees accompanied by vertebral rotation (2)
    
    
• most scoliosis cases (90%) are idiopathic (unknown aetiology), are diagnosed in puberty (adolescent), affect girls (90%) and commonly show a curve pattern which includes a right thoracic curve
• features of thoracic adolescent scoliosis include:
  • 90% are female
  • 90% convex to the right
  • the deformity is exaggerated by rib rotation
  • curves of greater than 70 degrees develop in 50%
    
    
• however, multiple curve patterns exist
  
  
• pain is not a typical feature, not even in severe curves
  • significant pain in association with a scoliotic deformity should raise awareness:
    • the scoliosis may be caused by pain of any source (reactive), may occur in association with an underlying spinal cord (syrinx, neurofibroma, tumour) or
    • spine (spondylolysis) pathology or
    • may itself be the cause of pain: marked thoracolumbar and or lumbar scoliosis may be painful due to asymmetric muscular load (1)

The condition will get worse without treatment, which involves braces for lesser curves; curves of greater than 45 degrees are generally treated with surgery (1,5)

• surgical treatment is indicated to halt curve progression (especially curves beyond 45 degrees) and improve cosmetic appearance
  • main goal of surgery is to achieve correction of deformity including rotation, a fusion of the structural deformity of the spine, which will prevent further progression

Adolescent idiopathic scoliosis with severe spinal curvature can be associated with negative health outcomes, including pulmonary disorders, disability, back pain, psychological effects, cosmetic issues and reduced quality of life (3).

The main tests used to screen for adolescent idiopathic scoliosis are the (Adam) Forward Bend Test (FBT), which may include a scoliometer, and Moiré topography, while radiography is employed to confirm diagnosis in a suspected case. The FBT is the most commonly used test, wherein assessors search for abnormalities and asymmetries of the spine as a patient bends forward.

A non-invasive, handheld device called a scoliometer can be used during the FBT to determine the angle of trunk rotation. Moiré topography is an alternative screening method that renders a 3D description of the back, highlighting any deformities present in the spine (4).

Notes:

• when examining a radiograph of the thoracic spine, the angle between intersecting line drawn perpendicular to the superior endplate of the top vertebrae and the inferior endplate of the bottom verterbrae is the Cobb angle (5) - the Cobb angle is a measure of the curvature of the spine in degress
  • a Cobb angle of 10 degree is regarded as a minimum angulation to define scoliosis.

Reference:

• (1) Hasler CC. Back pain during growth. Swiss Med Wkly. 2013 Jan 8;143:w13714.
• (2) Reamy BV, Slakey JB. Adolescent idiopathic scoliosis: review and current concepts. Am Fam Physician. 2001 Jul 1;64(1):111-6.
• (3) Grossman DC, Curry SJ, Owens DK, et al. Screening for adolescent idiopathic scoliosis: US preventive services task force recommendation statement. Jama 2018;319:165-172.
• (4) Willner S. Moiré topography—a method for school screening of scoliosis. Archives of orthopaedic and traumatic surgery 1979;95:181-185.
• (5) Choudhry NM et al. Adolescent Idiopathic Scoliosis Open Orthop 2016; 10: 143–154.