ABSTRACT
The aim of this chapter is to present two aspects of ambulatory problems in children with spastic cerebral palsy (CP). The first aspect concerns the identification of criteria for long-term prognosis with respect to walking in the young child with cerebral palsy. The second aspect concerns gait analysis and the difficulty in identifying the primary causes of gait abnormalities in children with CP who can walk. Cerebral palsy is a condition caused by non-progressive brain damage that usually occurs before, during or shortly after birth. The effect on the body can result in progressive deformities and disabilities that develop in a variety of different forms and degrees of severity depending upon the location and the extent of the damage. Despite the variety of the consequences there are certain common features including:
Abnormal muscle tone (e.g. dystonia and spasticity). Spasticity refers to increased tone or tension in a muscle whereas dystonia corresponds to sustained involuntary muscle contractions and spasms. Spastic cerebral palsy occurs with varying degrees of spasticity and is the most frequent form of CP. In spastic CP, the tone imbalance between agonist and antagonist muscle groups can lead to contractures of the shortened muscles;
Déficient recruitment of motor units (paretic component);
Unselective muscle control (e.g. co-activation);
Changes in the properties of the muscles (non-neural component), like the transformation of motor units that takes place following a supraspinal lesion (Dietz and Berger, 1995).
