Infantile scoliosis

Early onset scoliosis (EOS) includes all forms of scoliosis that present within the first 10 years of life

• in contrast to adolescent scoliosis, EOS is mostly of non-idiopathic origin and can be caused by congenital vertebral anomalies and neuromuscular or syndromic diseases
• growth rate within the first 12 months of life is the most rapid in a human’s lifetime
  • major spinal deformity might lead to a thoracic insufficiency syndrome (1)
    • a 33% prevalence of obstructive lung disease was observed in children with syndromic or congenital scoliosis (2)

By definition, early-onset scoliosis occurs before the age of 10 and is host to a heterogeneous spectrum of causes

• includes congenital scoliosis, structural scoliosis, neuromuscular scoliosis, syndromic scoliosis, and idiopathic scoliosis
  • congenital scoliosis results from a congenital disability in vertebral formation and segmentation
  • structural scoliosis results from a resulting body problem such as fused ribs, diaphragmatic hernia, or chest wall abnormalities
  • neuromuscular scoliosis is driven by neuromuscular disorders such as cerebral palsy or muscular dystrophy
  • syndromic scoliosis is associated with VACTERL (vertebral, anal atresia, cardiac defects, tracheoesophageal fistula, renal abnormalities, and limb defects) and neurofibromatosis
    
    
• infantile scoliosis, by nomenclature, includes those patients younger than the age of 3 at the time of presentation

• juvenile scoliosis includes those from ages 3 to 10
  
  
• early-onset scoliosis, from all causes, accounts for approximately 10% of all pediatric scoliosis cases

Patients will present with obvious spinal deformity with or without a known syndromic pathology. It is important to recognize that the initial presentation of a syndrome may be a spinal abnormality (1).

Management requires specialist review - may involve observation, bracing or surgery (4)

• general treatment and management aim to halt the progression of the spinal deformity. The goal is to increase thoracic volume to improve pulmonary and cardiac function
• spinal bracing is largely ineffective in this population and is poorly tolerated (3)
• surgery - various surgical options are available and there is innovation in this treatment area
  • growing rods can be inserted to allow for initial placement of proximal and distal anchors (hooks or pedicle screws) - these can be lengthened via surgical intervention but there are also magnetic growing rods which can be manipulated via magnetic control

Early-onset scoliosis is a heterogeneous constellation of diseases

• prognosis is linked largely to the co-morbidities and deformity at the time of presentation. This can be linked to the syndromic nature of the presentation, or more importantly, to the curve’s impact on thoracic growth and function
• progress of deformity can impact on lung development (2,3)
  • during the first 2 years, lung development is significant. By year 8, alveolar maturation will level off
  • children with limited thoracic function due to scoliosis development can see alveolar hypoplasia, abnormal ventilation, and decreased lung compliance
    • cardiac issues such as cor pulmonale and pulmonary hypertension can also present
    • the inability of the thoracic to appropriately lung growth and function are known as thoracic insufficiency syndrome

Prognosis of the deformity is related heavily to the skeletal maturity of the patient as well as a degree of deformity

• thoracic to sacral spine grows at approximately 2 cm per year for the first 5 years of life and then 1 cm per year from ages 5 to 10 with 1.8 cm per year until maturity. Rapid growth is seen in the first 5 years and then during the adolescent phase
• the rib-vertebral angle (RVAD) at the apical vertebrae is prognostic for the progression of early-onset scoliosis from idiopathic conditions (3)
  • an RVAD of greater than 20 degrees an initial presentation is more likely to progress

Reference:

• Akbarnia BA. Management themes in early onset scoliosis. J Bone Joint Surg Am. 2007;89(Suppl 1):42–54. doi: 10.2106/JBJS.F.01256.
• McPhail GL, Howells SA, Boesch RP, Wood RE, Ednick M, Chini BA, Jain V, Agabegi S, Sturm P, Wall E, Crawford A, Redding G. Obstructive lung disease is common in children with syndromic and congenital scoliosis: a preliminary study. J Pediatr Orthop. 2013;33(8):781–785. doi: 10.1097/BPO.0000000000000078.
• LeFever D, Menger RP. Infantile and Juvenile Scoliosis.StatPearls [Internet] January 2020
• https://www.nhs.uk/conditions/scoliosis/(accessed 17/6/2020)