T-Spine

Scoliosis

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Scoliosis, Idiopathic Scoliosis, Adolescent Scoliosis, Adolescent Idiopathic Scoliosis

  • Definitions
  1. Adolescent Idiopathic Scoliosis
    1. Spine with lateral curvature >10 degrees with Vertebral rotation in teens age 10 to 18 years
  • Epidemiology
  1. Prevalence: 1-3% 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 (by factor of 5-10 fold)
  • 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. Connective Tissue Disease
    1. Marfan Syndrome
    2. Ehlers-Danlos Syndrome
    3. Homocystinuria
  5. Miscellaneous Causes
    1. Asymmetric Pelvis (Leg Length Discrepancy)
    2. Spinal cord or Vertebral tumor
    3. Vertebral infection
    4. Spondylolysis
    5. Spondylolisthesis
    6. Scheuermann's Kyphosis
    7. Disc Herniation
  • 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. Both parents with Idiopathic Scoliosis confers 50 fold increased risk of children with Scoliosis requiring treatment
    3. Concordance in monozygotic twins: 73%
    4. Risk in first degree relatives: 11%
  • History
  1. Age of onset, progression and prior management
  2. Back pain or stiffness symptoms
  • Exam
  1. Typical lateral curvature shape is a backwards "S" (approaches 90% of cases)
    1. Right thoracic curve (convex to the right)
    2. Left lumbar curve (convex to the left)
  2. Landmarks
    1. Shoulder height
    2. Scapular prominence
    3. Flank crease
    4. Pelvic symmetry
    5. Leg Length Discrepancy
  3. Scoliosis-specific Exam
    1. See Scoliosis Examination
    2. Forward Bending Test
    3. Scoliometer (measures trunk rotation)
    4. Adam's Test
  4. Determine growth spurt
    1. Assessment Tools
    2. Measure Sitting Height (Truncal Height) q3 months
    3. Obtain Risser Grading (Iliac XRay)
  5. Functional exam
    1. Neurologic Exam
    2. Gait
  • Precautions
  • Red Flags
  1. Left thoracic curve (S curve)
    1. Thoracic curve convex to the left and lumbar convex to the right
      1. Normally Scoliosis thoracic curve is convex to the right (see signs above)
    2. Spinal cord tumor
    3. Arnold-Chiari Malformation
    4. Occult Spinal Dysraphism (Spina Bifida Occulta)
  2. Severe back pain
    1. Scoliosis rarely causes significant pain
    2. Evaluate for other causes of back pain
  3. Neurologic deficits
    1. Spinal Dysraphism signs (see Cutaneous Signs of Dysraphism)
    2. Neurofibromatosis stigmata (e.g. Cafe Au Lait spots)
  4. Other syndromes associated with Scoliosis secondary cause
    1. Marfan's Syndrome
  • Evaluation
  • Screening
  1. Universal school screening is no longer routinely performed in the United States
    1. Screening recommendations are controversial and vary by guideline organizations
  2. Screening is recommended by AAOS and AAP as of 2007
    1. Screening is a low risk procedure and plain film Spine XRays have minimal radiation
    2. Scoliosis Screening is recommended at age 10 and age 12 years in girls, and at age 13-14 years in boys
    3. http://www.aaos.org/about/papers/position/1122.asp
  3. Screening is not recommended by USPTF or AAFP as of 2004
    1. Screening has a very low yield for identifying Scoliosis requiring management
    2. Screening has a high False Positive Rate and results in unnecessary exams and xrays
    3. http://www.uspreventiveservicestaskforce.org/uspstf/uspsaisc.htm
  • Imaging
  • Scoliosis
  1. Thoracic Spine XRay (may require full spine)
    1. See Scoliosis XRay (Cobb Angle)
    2. Indications
      1. See Scoliosis Examination (Forward Bending Test, Scoliometer)
      2. BMI <85%: Scoliometer measurement 7 degrees or more of trunk rotation (~20 degree Cobb Angle)
      3. BMI >85%: Scoliometer measurement 5 degrees or more of trunk rotation (~10 degree Cobb Angle)
    3. Images
      1. BackScoliosisXRay.gif
  2. Spine 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
  3. Skeletal maturity evaluation
    1. Risser Grade
      1. Iliac Apophysis Ossification grading from Grade 1-5 (25% to 100% ossification)
    2. Simplified Tanner-Whitehouse 3 Skeletal Maturity Assessment (Digital Age Score)
      1. Based on small hand bone imaging findings
      2. Stages 1-8 (with stage 8 correlating with Risser Grade 5)
  • Differential Diagnosis
  1. Nonstructural Scoliosis
    1. Leg Length Discrepancy
    2. Local inflammation
  2. Structural Scoliosis
    1. See Causes above
  • Prognosis
  • Natural Course
  1. Skeletal Curve before skeletal maturity (highest risk for progression)
    1. Cobb Angle 20-29 degrees
      1. Risser Grade 0 to 1: 68% probability of progression
      2. Risser Grade 2 to 4: 23% probability of progression
  2. Skeletal curves at skeletal maturity
    1. Cobb Angle <20 degrees
      1. Resolve spontaneously 50% of cases
    2. Cobb Angle <30 degrees
      1. Progress minimally
    3. Cobb Angle 40-50 degrees
      1. Progress 10-15 degree lifetime
    4. Cobb Angle >50 degrees
      1. Progress 1-2 degrees/year
  • Risk factors
  • Scoliosis severity and progression
  1. Larger curves (25 degrees or more) progress more severely
    1. Initial Cobb Angle measurement is the most important predictor of Scoliosis requiring formal management
  2. Skeletal maturity determines
    1. Skeletal maturity (by Riser Grade or Digital skeletal age score) best predicts the likelihood of Scoliosis progression
    2. Early adolescence is associated with the greatest risk of curve change
  3. Other factors impacting Scoliosis severity and progression
    1. Female gender
    2. Higher apex Vertebral level
    3. Thoracic or thoracolumbar curve (70% progression)
    4. Double major curves (70% progression)
  1. Cobb Angle 10-19 degrees
    1. Scoliosis XRay every 6 months
  2. Cobb Angle 20-29 degrees
    1. Scoliosis XRay with Risser Grading XRay of the Pelvis every 6 months
    2. Spine referral unless knowledgeable about monitoring and Scoliosis bracing
    3. Scoliosis bracing for Cobb Angle >25 degrees and Risser Grades 0-3
  3. Cobb Angle 30-40 degrees
    1. Spine referral
    2. Bracing
  4. Cobb Angle >40 degrees
    1. Spine referral
    2. Surgery may be indicated
  • Management
  • Specific protocols
  1. Protocol based on progression risk (Cobb Angle and Risser Score)
    1. See Progression risk factors and protocol above
    2. Overall trend in U.S. is for less imaging and less formal management (bracing or surgery)
  2. Observation protocol
    1. Observe for progression until stable or maturity
    2. Examine every 3-6 months
    3. Imaging, bracing and referral indications as above
  3. Spine referral indications
    1. Cobb Angle >20-25 degrees (or Scoliometer angle >7 degrees)
      1. Unless primary provider is comfortable with observation, Scoliosis bracing and monitoring
    2. Cobb Angle >30 degrees
      1. All patients with Scoliosis of this severity
    3. Atypical findings (see red flags above)
  4. Physical Therapy
    1. Mixed study results for benefit
    2. May prevent progression of Scoliosis in Cobb Angle <25 degrees
    3. Romano (2012) Cochrane Database Syst Rev (8):CD007837 [PubMed]
    4. Monticone (2014) Eur Spine J 23(6): 1204-14 [PubMed]
  5. Spine bracing
    1. Typically indicated for Cobb Angle >25 degrees with Risser Grade 0-3
    2. Bracing is controversial and noncompliance is high
    3. Appears to slow moderate Scoliosis progression
      1. Weinstein (2013) N Engl J Med 369(16): 1512-21 [PubMed]
    4. Thoracolumbar-Sacral Orthosis (TLSO)
    5. Cervicothoracolumbar-Sacral Orthosis (CTLSO)
  6. Surgery (rod placement, bone grafting)
    1. Typically indicated for Cobb Angle >40 degrees with Risser Grade 0-3
  • Complications
  1. Most Scoliosis is asymptomatic (esp. Cobb Angle <40 degrees)
  2. Symptomatic Scoliosis may occur with Cobb Angles >40-50 degrees
    1. Musculoskeletal pain
    2. Cosmetic deformity of the back or trunk
    3. Restrictive Lung Disease