Electrophysiological studies in children with paralytic poliomyelitis.

H-reflex latency (H-RL) and H/M ratio were measured in normal children and children with paralytic poliomyelitis of 1-3 years of age. The H-RL was considerably increased in both the involved and uninvolved limbs of the patients, whereas the H/M ratio did not differ. The Mmax value in the involved limb was very low, and therefore, a corrected H/M ratio was calculated for that side only. The corrected H/M ratio was significantly less than the H/M ratio observed in the uninvolved and control limbs. The distal motor latency was also increased in the involved side.