Scoliosis

1. Epidemiology
   1. Prevalence: 2% of adolescent population
   2. Age
      1. Girls: After 9-10 years old
      2. Boys: After 11-12 years old
   3. Gender
      1. Boys and girls affected equally
      2. Girls are much more likely to significantly progress
2. Causes
   1. Idiopathic Scoliosis (85%)
   2. Congenital Causes
      1. Failed Vertebral development (e.g. Hemivertebra)
      2. Developmental failure of Vertebrae to segment
   3. Neuromuscular disorders
      1. Neurofibromatosis
      2. Syringomyelia
      3. Diastematomyelia (congenital spinal cord splitting)
      4. Cerebral Palsy
      5. Muscular Dystrophy
      6. Myelomeningocele
      7. Spinal muscular atrophy
      8. Friedreich ataxia
      9. Tethered cord
      10. Syrinx
   4. Miscellaneous Causes
      1. Asymmetric Pelvis
      2. Spinal cord or Vertebral tumor
      3. Vertebral infection
   5. Connective Tissue Disease
      1. Marfan Syndrome
      2. Ehlers-Danlos Syndrome
      3. Homocystinuria
3. Pathophysiology
   1. Lateral curvature of the spine
      1. Rotation of Vertebrae about vertical axis
   2. Idiopathic Scoliosis is inherited
      1. Autosomal dominant inheritance (variable penetrance)
      2. Concordance in monozygotic twins: 73%
      3. Risk in first degree relatives: 11%
4. History
   1. Age of onset, progression and prior management
   2. Back pain or stiffness symptoms
5. Signs
   1. Scoliosis screening should begin at age 6 years
   2. Right thoracic and left lumbar curvature is the norm
   3. Landmarks
      1. Shoulder height
      2. Scapular prominence
      3. Flank crease
      4. Pelvic symmetry
      5. Leg Length Discrepancy
   4. See Scoliosis Examination
      1. Forward Bending Test
      2. Scoliometer (measures trunk rotation)
      3. Adam's Test
   5. Determine growth spurt
      1. Assessment Tools
      2. Measure Sitting Height (Truncal Height) q3 months
      3. Obtain Risser Grading (Iliac XRay)
   6. Functional exam
      1. Neurologic Exam
      2. Gait
   7. Red Flags
      1. Left thoracic curve (possible spinal cord lesion)
      2. Neurofibromatosis stigmata
      3. Marfan's Syndrome stigmata
6. Radiology
   1. Thoracic Spine XRay (may require full spine)
      1. See Scoliosis XRay (Cobb Angle)
      2. Images
         1. 
   2. Spine CT or MRI for atypical Scoliosis
      1. Left thoracic curve
      2. Onset of Scoliosis before age 8 years
      3. Rapid curve progression >1 degree per month
      4. Neurologic deficit or pain
7. Differential Diagnosis
   1. Nonstructural Scoliosis
      1. Leg Length Discrepancy
      2. Local inflammation
   2. Structural Scoliosis
      1. See Causes above
8. Course: Curves at skeletal maturity
   1. Curves <20 degrees: Resolve spontaneously 50% of cases
   2. Curves <30 degrees: Progress minimally
   3. Curve 40-50 degrees: 10-15 degree lifetime progression
   4. Curve >50 degrees: Progresses 1-2 degrees per year
9. Course: Curves before skeletal maturity
   1. Spinal Curvature 20-29 degrees
      1. Risser Grade 0 to 1: 68% probability of progression
      2. Risser Grade 2 to 4: 23% probability of progression
10. Progression risk factors
    1. Females
    2. Higher apex Vertebral level
    3. Thoracic or thoracolumbar curve (70% progression)
    4. Double major curves (70% progression)
    5. Young children at beginning of growth curve
    6. Larger curves progress more severely
11. Management
    1. Treatment based on progression risk
       1. See Progression risk factors above
    2. Orthopedic referral indications
       1. Cobb Angle
          1. Angle exceeds 20 degrees
       2. Scoliometer
          1. Angle of trunk rotation exceeds 7 degrees
    3. Observation protocol (curves <10 to 15 degrees)
       1. Observe for progression until stable or maturity
       2. Examine every 3-4 months
       3. Indications to Repeat Thoracic XRay every 6 months
          1. Curve increasing
          2. Child has growth spurt
    4. Management Strategies
       1. Cobb Angle greater than 20 degrees
          1. Bracing is controversial and noncompliance is high
          2. Bracing options
             1. Thoracolumbar-Sacral Orthosis (TLSO)
             2. Cervicothoracolumbar-Sacral Orthosis (CTLSO)
       2. Cobb Angle greater than 45 to 50 degrees
          1. Surgery (rod placement, bone grafting)
12. References
    1. Greene (2001) Musculoskeletal Care, AAOS, p. 696-9
    2. Greiner (2002) Am Fam Physician 65(9):1817-22
    3. Skaggs (1996) Am Fam Physician 53(7): 2327-34