Electrophysiologic correlates of peripheral nervous system maturation in infancy and childhood.

Peripheral nervous system maturation in infancy and childhood varies with age, especially during the first 2 years of life. Electrophysiologic values therefore changes significantly between different age groups within these first 2 years and are different from adult values. Normal values of motor and sensory nerve conduction, distal motor latency, F-wave latency, and evoked response amplitude of peripheral nerves commonly tested are reported in 155 healthy children in seven age groups from 1 week to 14 years. Interval changes are clearly shown, and in comparison with adult values, the whole group has significantly slower nerve conduction velocities, with reduced muscle and nerve evoked response amplitudes. These differences are important to recognize when evaluating the peripheral nervous system of children.