Juvenile Idiopathic Scoliosis - Spine

summary
- Juvenile Idiopathic Scoliosis is a coronal plane spinal deformity which most commonly presents in children between ages 4 and 10.
- Diagnosis is made with full-length standing PA and lateral spine radiographs. MRI studies are indicated in children <10 years old with a curve > 20°.
- Treatment can be observation, bracing, or surgical management depending on the skeletal maturity of the patient, magnitude of deformity, and curve progression.

Epidemiology
- Incidence
  - 15% of all idiopathic scoliosis cases
- Demographics
  - females > males
- Anatomic location
  - most commonly appear as a right main thoracic curve

Etiology
- Associated conditions
  - high incidence of neural axis abnormalities (18-25%)
    
    syringomyelia
    
    cyst or tubular cavity within spinal cord
    
    can be seen in a scoliotic curve without rotation
    
    can manifest as an asymmetric umbilicus reflex
    
    Arnold-Chiari syndrome
    
    cerebellar tonsil are elongated and protruding through the opening of the base of the skull and blocking CSF flow)
    
    tethered cord
    
    dysraphism
    
    spinal cord tumor

Classification
- Early onset scoliosis (EOS)
  - early-onset scoliosis is a broader category including scoliosis in children <10 years old. It includes
    
    infantile idiopathic scoliosis
    
    juvenile idiopathic scoliosis
    
    congenital scoliosis
    
    neurogenic scoliosis
    
    syndromic scoliosis
    
    Marfan's
    
    Down's syndrome

Presentation
- History
  - important to determine when deformity was first noticed and any observed progression
  - get perinatal history
- Presentation
  - failure to develop bowel and bladder control by age ~ 3 or 4 may indicate neurologic involvement
  - patients often referred from school screening where a 7° curve on scoliometer during Adams forward bending test is considered abnormal
    
    7° correlates with 20° coronal plane curve
- Physical exam
  - general inspection
    
    cafe-au-lait spots (neurofibromatosis)
    
    leg length inequality
    
    shoulder height differences
    
    truncal shift
    
    waist asymmetry and pelvic tilt
    
    foot deformities (cavovarus)
    
    can suggest neural axis abnormalities and warrant a MRI
  - spine inspection
    
    midline skin defects
    
    hairy patches
    
    dimples (signs of spinal dysraphism)
    
    nevi
    
    rib rotational deformity (rib prominence)
    
    Adams forward bending test
    
    axial plane deformity indicates structural curve
    
    forward bending sitting test
    
    can eliminate leg length inequality as cause of scoliosis
  - neurologic
    
    motor
    
    upper and lower extremities exam
    
    reflexes
    
    abnormal abdominal reflexes
    
    associated with the presence of a syrinx
    
    gently stroking each abdominal quadrant should cause contraction of the abdominal muscles
    
    clonus
    
    Hoffman sign
    
    Babinski
  - gait analysis

Imaging
- Radiographs
  - PA and lateral upright images are used to assess curve severity
    
    treatment based on Cobb angle
  - Cobb angle
    
    > 10° defined as scoliosis
    
    intra-interobserver error of 3-5°
    
    bending radiographs can help determine which curves require fusion
- MRI
  - indicated in children <10 years old with a curve > 20°
    
    even in the absence of neurologic symptoms
    
    must rule out neural axis abnormalities (e.g., syringomyelia)
    
    presence of left-sided thoracic curve

Treatment
- Nonoperative
  - observation
    
    indications
    
    curves < 20°
    
    technique
    
    frequent radiographs to observe for curve progression
  - bracing
    
    indications
    
    curves 20 - 50°
    
    designed to prevent curve progression, not correct the curve
    
    relative contraindication to bracing is thoracic hypokyphosis
    
    technique
    
    16-23h/day until skeletal growth completed or surgery indicated
- Operative
  - non-fusion procedures (growing rods, VEPTR)
    
    indications
    
    curves > 50° in small children with significant growth remaining
    
    allows continued spinal growth over unfused segments
    
    definitive PSF + ASF performed when the child has grown and is closer skeletal maturity
    
    traditional growing rods associated with greater curve correction and truncal height gain than VEPTR constructs
  - anterior / posterior spinal fusion
    
    indications
    
    curves > 50° in younger patients
    
    required in order to prevent crankshaft phenomenon
  - posterior spinal fusion
    
    indications
    
    curve > 50° in older patients near skeletal maturity
    
    remains gold standard for thoracic and double major curves (most cases)
  - anterior spinal fusion
    
    indications
    
    curve > 50°
    
    best for thoracolumbar and lumbar cases with a normal sagittal profile

Complications
- Crankshaft phenomenon

Prognosis
- High risk of progression
  - 70% require treatment (50% bracing, 50% surgery)
- Very few experience spontaneous resolution
- Can be fatal if not treated appropriately

Action	Numeric Key	Letter Key	Function Key
Show Bullets		S	Enter (frontside only)
20%	1	N
40%	2	H
60%	3	F	Enter (backside only)
80%	4	E
100%	5	M
Toss	0	T