II. Definitions
- Adolescent Idiopathic Scoliosis
- Spine with lateral curvature >10 degrees with Vertebral rotation in teens age 10 to 18 years
III. Epidemiology
- Prevalence: 1-3% of adolescent population
- Age
- Girls: After 9-10 years old
- Boys: After 11-12 years old
- Gender
- Boys and girls affected equally
- Girls are much more likely to significantly progress (by factor of 5-10 fold)
IV. Causes
- Idiopathic Scoliosis (85%)
- Congenital Causes
- Neuromuscular disorders
- Neurofibromatosis
- Syringomyelia
- Diastematomyelia (congenital spinal cord splitting)
- Cerebral Palsy
- Muscular Dystrophy
- Myelomeningocele
- Spinal muscular atrophy
- Friedreich Ataxia
- Tethered Cord
- Syrinx
- Connective Tissue Disease
- Miscellaneous Causes
- Asymmetric Pelvis (Leg Length Discrepancy)
- Spinal cord or Vertebral tumor
- Vertebral infection
- Spondylolysis
- Spondylolisthesis
- Scheuermann's Kyphosis
- Disc Herniation
V. Pathophysiology
- Lateral curvature of the spine
- Rotation of Vertebrae about vertical axis
- Idiopathic Scoliosis is inherited
- Autosomal Dominant inheritance (variable penetrance)
- Both parents with Idiopathic Scoliosis confers 50 fold increased risk of children with Scoliosis requiring treatment
- Concordance in monozygotic twins: 73%
- Risk in first degree relatives: 11%
VI. History
- Age of onset, progression and prior management
- Back pain or stiffness symptoms
VII. Exam
- Typical lateral curvature shape is a backwards "S" (approaches 90% of cases)
- Right thoracic curve (convex to the right)
- Left lumbar curve (convex to the left)
- Landmarks
- Shoulder height
- Scapular prominence
- Flank crease
- Pelvic symmetry
- Leg Length Discrepancy
- Scoliosis-specific Exam
- See Scoliosis Examination
- Forward Bending Test
- Scoliometer (measures trunk rotation)
- Adam's Test
- Determine growth spurt
- Assessment Tools
- Measure Sitting Height (Truncal Height) q3 months
- Obtain Risser Grading (Iliac XRay)
- Functional exam
VIII. Precautions: Red Flags
- Left thoracic curve (S curve)
- Thoracic curve convex to the left and lumbar convex to the right
- Normally Scoliosis thoracic curve is convex to the right (see signs above)
- Spinal cord tumor
- Arnold-Chiari Malformation
- Occult Spinal Dysraphism (Spina Bifida Occulta)
- Thoracic curve convex to the left and lumbar convex to the right
- Severe back pain
- Scoliosis rarely causes significant pain
- Evaluate for other causes of back pain
- Neurologic deficits
- Spinal Dysraphism signs (see Cutaneous Signs of Dysraphism)
- Neurofibromatosis stigmata (e.g. Cafe Au Lait spots)
- Other syndromes associated with Scoliosis secondary cause
IX. Evaluation: Screening
- Universal school screening is no longer routinely performed in the United States
- Screening recommendations are controversial and vary by guideline organizations
- Screening is recommended by AAOS and AAP as of 2007
- Screening is a low risk procedure and plain film Spine XRays have minimal radiation
- Scoliosis Screening is recommended at age 10 and age 12 years in girls, and at age 13-14 years in boys
- http://www.aaos.org/about/papers/position/1122.asp
- Screening is not recommended by USPTF or AAFP as of 2004
- Screening has a very low yield for identifying Scoliosis requiring management
- Screening has a high False Positive Rate and results in unnecessary exams and xrays
- http://www.uspreventiveservicestaskforce.org/uspstf/uspsaisc.htm
X. Imaging: Scoliosis
-
Thoracic Spine XRay (may require full spine)
- See Scoliosis XRay (Cobb Angle)
- Indications
- See Scoliosis Examination (Forward Bending Test, Scoliometer)
- BMI <85%: Scoliometer measurement 7 degrees or more of trunk rotation (~20 degree Cobb Angle)
- BMI >85%: Scoliometer measurement 5 degrees or more of trunk rotation (~10 degree Cobb Angle)
- Images
- Spine MRI for atypical Scoliosis
- Left thoracic curve
- Onset of Scoliosis before age 8 years
- Rapid curve progression >1 degree per month
- Neurologic deficit or pain
- Skeletal maturity evaluation
- Risser Grade
- Iliac Apophysis Ossification grading from Grade 1-5 (25% to 100% ossification)
- Simplified Tanner-Whitehouse 3 Skeletal Maturity Assessment (Digital Age Score)
- Based on small hand bone imaging findings
- Stages 1-8 (with stage 8 correlating with Risser Grade 5)
- Risser Grade
XI. Differential Diagnosis
- Nonstructural Scoliosis
- Leg Length Discrepancy
- Local inflammation
- Structural Scoliosis
- See Causes above
XII. Prognosis: Natural Course
- Skeletal Curve before skeletal maturity (highest risk for progression)
- Cobb Angle 20-29 degrees
- Risser Grade 0 to 1: 68% probability of progression
- Risser Grade 2 to 4: 23% probability of progression
- Cobb Angle 20-29 degrees
- Skeletal curves at skeletal maturity
- Cobb Angle <20 degrees
- Resolve spontaneously 50% of cases
- Cobb Angle <30 degrees
- Progress minimally
- Cobb Angle 40-50 degrees
- Progress 10-15 degree lifetime
- Cobb Angle >50 degrees
- Progress 1-2 degrees/year
- Cobb Angle <20 degrees
XIII. Risk factors: Scoliosis severity and progression
- Larger curves (25 degrees or more) progress more severely
- Initial Cobb Angle measurement is the most important predictor of Scoliosis requiring formal management
- Skeletal maturity determines
- Skeletal maturity (by Riser Grade or Digital skeletal age score) best predicts the likelihood of Scoliosis progression
- Early adolescence is associated with the greatest risk of curve change
- Other factors impacting Scoliosis severity and progression
- Female gender
- Higher apex Vertebral level
- Thoracic or thoracolumbar curve (70% progression)
- Double major curves (70% progression)
XIV. Management: Immature Risser Grade 0-4
-
Cobb Angle 10-19 degrees
- Scoliosis XRay every 6 months
-
Cobb Angle 20-29 degrees
- Scoliosis XRay with Risser Grading XRay of the Pelvis every 6 months
- Spine referral unless knowledgeable about monitoring and Scoliosis bracing
- Scoliosis bracing for Cobb Angle >25 degrees and Risser Grades 0-3
-
Cobb Angle 30-40 degrees
- Spine referral
- Bracing
-
Cobb Angle >40 degrees
- Spine referral
- Surgery may be indicated
XV. Management: Specific protocols
- Protocol based on progression risk (Cobb Angle and Risser Score)
- See Progression risk factors and protocol above
- Overall trend in U.S. is for less imaging and less formal management (bracing or surgery)
- Observation protocol
- Observe for progression until stable or maturity
- Examine every 3-6 months
- Imaging, bracing and referral indications as above
- Spine referral indications
- Cobb Angle >20-25 degrees (or Scoliometer angle >7 degrees)
- Unless primary provider is comfortable with observation, Scoliosis bracing and monitoring
- Cobb Angle >30 degrees
- All patients with Scoliosis of this severity
- Atypical findings (see red flags above)
- Cobb Angle >20-25 degrees (or Scoliometer angle >7 degrees)
- Physical Therapy
- Mixed study results for benefit
- May prevent progression of Scoliosis in Cobb Angle <25 degrees
- Romano (2012) Cochrane Database Syst Rev (8):CD007837 [PubMed]
- Monticone (2014) Eur Spine J 23(6): 1204-14 [PubMed]
- Spine bracing
- Typically indicated for Cobb Angle >25 degrees with Risser Grade 0-3
- Bracing is controversial and noncompliance is high
- Appears to slow moderate Scoliosis progression
- Thoracolumbar-Sacral Orthosis (TLSO)
- Cervicothoracolumbar-Sacral Orthosis (CTLSO)
- Surgery (rod placement, bone grafting)
- Typically indicated for Cobb Angle >40 degrees with Risser Grade 0-3
XVI. Complications
- Most Scoliosis is asymptomatic (esp. Cobb Angle <40 degrees)
- Symptomatic Scoliosis may occur with Cobb Angles >40-50 degrees
- Musculoskeletal pain
- Cosmetic deformity of the back or trunk
- Restrictive Lung Disease
XVII. References
- Greene (2001) Musculoskeletal Care, AAOS, p. 696-9
- Greiner (2002) Am Fam Physician 65(9):1817-22 [PubMed]
- Horne (2014) Am Fam Physician 89(3):193-8 [PubMed]
- Kuznia (2020) Am Fam Physician 101(1):19-23 [PubMed]
- Skaggs (1996) Am Fam Physician 53(7): 2327-34 [PubMed]