Congenital Scoliosis

Congenital Scoliosis is an abnormal lateral curvature of the spine, resulting from disruption of normal vertebral development.

Although there are many types of defects observed in Congenital Scoliosis, all result from abnormal formation and segmentation of the vertebral precursors, called somites. Developmental studies in animal models have identified many genes regulating somite formation and segmentation. The interaction of environmental factors and these genes, is thought to be disrupted resulting in deformities such as congenital scoliosis.

A basic science research program and a large, multi-centre clinical genetic study of Congenital Scoliosis and Kyphosis have been established at our institution. Studying the developmental mechanisms in vertebral patterning may aid in the identification of some protective factors for normal spinal development, towards the prevention of disfiguring Congenital Scoliosis.

While Congenital Scoliosis is often recognised at birth, more subtle spinal defects can remain undetected. A key feature of Congenital Scoliosis is the presence of one or more abnormally formed vertebrae. When these anomalies are identified, the curve should be classified as Congenital, even if the deformity is not apparent until adolescence.

The vertebrae of the spine are formed during development by segmentation of the precursor spine tissue, in a process called somitogenesis. In this process, segments of tissue called somites are formed in pairs surrounding what will eventually become the spinal cord. When somitogenesis is disrupted even slightly, as has been done in animal models, Congenital vertebral defects identical to those in Congenital Scoliosis have resulted. Developmental studies in animal models have identified many genes regulating somite formation and segmentation. Recently, genes in the "notch" family have been shown to regulate development of vertebral precursors in the mouse and defects in human notch genes have been associated with Congenital vertebral defects.

Congenital vertebral anomalies have been produced in newborn animals experimentally by transient hypoxia and transient exposure to toxic elements during fatal period. In these studies, many gross vertebral and associated skeletal defects have been induced, including hemi vertebrae, vertebral fusions, fragmented vertebral bodies, bifid ribs or junctions of two or more ribs. The nature and extent of skeletal malformations induced have been dependent upon the precise stage of somite differentiation at the time when maternal stress has been induced.

Currently, researchers hypothesise that the environmental factors affect the delivery of the genetic instructions during development, so it is the close interaction of genes and environment that produce the normal spine. This interaction is thought to be disrupted in deformities such as Congenital Scoliosis.