Infantile scoli (0-3)
Approach to Infantile Idiopathic Scoliosis
Traditionally, idiopathic scoliosis has been divided into 3 categories based on age of onset:
– infantile (0-3 years) – juvenile (4-9 years) – adolescent (10 years -maturity)
– arguably, growth velocity is increased in infancy and adolescence, but remains constant during the juvenile period, and so it is probably not worth assigning a category to the juveniles. Thus, it may make more sense to conceptually break it down into two groups: early onset, referring to those in which the deformity arises before age 5, and late onset referring to those in which the deformity arises after age 5.
– the key is that if significant thoracic deformity is present before age 5, the patient is in the category where he/she is at real risk of subsequent cardiopulmonary compromise down the road.
Characteristics of “infantile” or “early onset” idiopathic scoliosis
– males more commonly affected than females
– three quarters are convex to the LEFT, unlike adolescent idiopathics where the vast majority are convex right.
– thoracic and thoracolumbar curves tend to resolve, but double structural curves with a thoracic component have a definite progressive potential.
– initial curve size and amount of associated rotation are prognostic factors
– in general, most curves resolve spontaneously
Mehta Rib Vertebral Angle Difference – a measure of rotation
– at the apical vertebrae, measure the angle of the neck of the rib against vertical on both sides (on the convexity, the angle is more acute; one the concavity, the angle is more obtuse). The difference between these two angles is the rib vertebral angle difference (RVAD). If the RVAD exceeds 20, the curve is likely to be progressive.
The RVAD greater than 20 is the single most important factor predicting progression.
– start searching for other reasons for the deformity
– tethered cord?
– congenital failure of formation or segmentation.
– look for other visceral abnormalities
– x-rays to see if this is a congenital curve
– then measure the RVAD
– if any suspicion that this is not an “idiopathic” curve, get an MRI!
– most resolve on their own
– serial casting (elongation derotation flexion casting) is the conservative treatment of choice
– the indications for casting are unclear, but any low-weight floppy child with a big curve and an RVAD over 20 should be casted.
– casting is usually done in the OR under GA
– no point in casting past 5 years of age (growth velocity has plateaued.) Can be braced after this
– surgery when serial casting has failed to halt progression – requires anterior discectomy over four or five apical segments, then growing rod posteriorly.