Abstract
Several workers consider that the aetiology of adolescent idiopathic scoliosis (AIS) involves undetected neu-romuscular dysfunction. During normal development the central nervous system (CNS) has to adapt to the rapidly growing skeleton of adolescence, and in AIS also to developing spinal asymmetry from whatever cause. A new etiologic concept is proposed after examining the following evidence:
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anomalous extra-spinal left-right skeletal length asymmetries of upper arms, ribs, ilia and lower limbs suggesting that asymmetries may also involve vertebral body and costal growth plates;
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growth velocity and curve progression in relation to scoliosis curve expression;
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the CNS body schema, parietal lobe and temporoparietal junction in relation to postural mechanisms; and
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human upright posture and movements of spine and trunk.
The central of four requirements is maturational delay of the CNS body schema relative to skeletal maturation during the adolescent growth spurt that disturbs the normal neuro-osseous timing of maturation. With the development of an early AIS deformity at a time of rapid spinal growth the association of CNS maturational delay results in postural mechanisms failing to balance a lateral spinal deformity in an upright moving trunk that is larger than the information on personal space (self) established in the brain by that time of development. It is postulated that CNS maturational delay allows scoliosis curve progression to occur – unless the delay is temporary when curve progression would cease. The concept brings together many findings relating AIS to the nervous and musculoskeletal systems and suggests brain morphometric studies in subjects with progressive AIS.
Correspondence should be addressed to: Dr Caroline Goldberg, The Research Centre, Our Lady’s Children’s Hospital Crumlin, Dublin 12, Ireland.
