Scoliosis, idiopathic

• Kyphoscoliosis

• 737.30 Scoliosis (and kyphoscoliosis) idiopathic

• M41.20 Other idiopathic scoliosis, site unspecified

• 4B: Impaired Posture

Description

• Three-dimensional curvatures of the spine and trunk
  • Lateral curve is an S- or C-shaped curve in the sagittal plane
  • Torsional component with vertebrae rotating toward the convexity
  • Anteroposterior distortion leads to hyperkyphosis and/or hyperlordosis in the coronal plane
• Functional lateral curvature of the spine, typically reversible
• Structural lateral curvature of the spine, fixed
  • Most commonly idiopathic
  • May be present in conjunction with another condition
  • 80 to 85% are idiopathic
  • Congenital
    • Hemi-vertebrae malformation
• Infantile onset < 3 years old
• Juvenile onset 3 to 9 years old
• Adolescent idiopathic scoliosis (AIS) onset 10 to 18 years old
• Adult onset >18 years
• AIS is the most common form and occurs in otherwise healthy children during puberty (80 to 85% of cases)
• Relatively benign condition
• Named for the side of the convexity of the lateral curve (right=dextroscoliosis; left=levoscoliosis)
• Degree of curvature most commonly defined by the Cobb method, radiographically
• Increased risk of curve progression during growth spurts in adolescents

Essentials of Diagnosis

• Adam’s forward bending test
  • Patient stands with back to the clinician and then actively bends forward towards the floor.
  • Exam reveals a rib hump, which represents the posteriorly displaced rib angles due to vertebral rotation on the convex side of the curve.
    • Functional: During forward bending, the rib hump disappears with ipsilateral side-bending.
    • Structural: During forward bending, the rib hump persists with ipsilateral side-bending.
  • Inclinometer measuring device may be utilized to clinically document progression or regression of curve without radiation exposure.
• X-rays (occiput to sacrum) used to define severity of curve
  • Anteroposterior view with Cobb angle measurements
    • A perpendicular line at the top of the vertebral body of the superior most acutely angles vertebral segment intersecting a similar line at the inferior most acutely angles segment
    • The angle of intersection of two lines placed perpendicular to the above two lines is considered the Cobb angle for that lateral spine curvature
  • Lateral view to identify hyperkyphosis and/or lordosis
  • Also used to rule out primary structural or mass deformities causing a secondary scoliotic curvature
  • Cobb angle measurements: limited in ability to determine spinal flexibility and the three-dimensional aspect of the condition. Tends to overestimate the curve.
  • Cobb Angle measurements
    • <10 degrees is a normal variation and unlikely to progress
    • 10 to 35 degrees often treated conservatively, depending on rate of progression
    • >35 degrees considered for surgical intervention but guidelines and outcomes vary
    • >50 degrees considered surgical to prevent cardiopulmonary compromise, rib motion restriction, pain, cosmetic deformity
• Skeletal maturity
• MRI
  • Used to identify spinal cord and brain stem abnormalities
• Three-dimensional computerized modeling techniques
  • Advanced computer modeling able to create three-dimensional images can reduce the number of x-rays needed to monitor scoliosis over time

General Considerations

• Occurs frequently in the general population