Current concepts of surgical management of deformities of the lower extremities in cerebral palsy.

In cerebral palsy, principles involved in proper selection of orthopedic management of the lower limbs include diagnosis, timing, goals, degree of involvement, linkage, kinetic electromyography, retention of neonatal automatisms, and dynamic versus fixed deformity, as well as the physical plant and professional skills. Specific lower extremity problems in the hip, knee, ankle, and foot must be analyzed and management for each should be approached on a rational basis. Unsolved enigmatic problems of etiology, pathways of neonatal automatisms that impose abnormal posturing, neurophysiologic mechanisms of spasticity, athetosis, rigidity and ataxia, pathogenesis of contracture, linkage biomechanics, and the neurologic, including the biomechanical effects of surgical intervention, require special research programs.