Aetiological pathways to spastic cerebral palsy.

An aetiological pathway is a sequence of interdependent events culminating in disease. Recognition of such pathways can be clinically useful if it suggests more effective methods of disease prevention. Kernicterus arising from feto-maternal Rhesus incompatibility and resulting in choreoathetosis comprises an aetiological pathway to cerebral palsy. The failure to recognise sufficient causes or to intervene effectively when a sufficient cause is suspected in the majority of cerebral palsy cases suggests that there may be other aetiological pathways. Evidence for other pathways was sought in the data from the Western Australian case-control study of 183 children with spastic cerebral palsy. Two or more factors likely to be of aetiological significance were recognised for nearly one-third of cases. As anticipated, the numbers with any specific combination of factors were small, pointing to the need for collaborative studies to obtain larger numbers to confirm their aetiological significance. The implications for the true proportion of cases with multifactorial aetiology and the problems inherent in such an investigation are discussed.