The central conduction time in posterior tibial and pudendal nerve somatosensory evoked potentials

The somatosensory evoked potentials (SEPs), following stimulation of both t he posterior tibial nerve (PTSEP) and pudendal nerve (PNSEP), comprise of t he lumbar negative, subcortical and cortical potential. These can be used t o assess the long somatosensory pathway, including peripheral, intraspinal and intracranial conduction along the entire length. This study aimed to co mpare the central conduction time between the PTSEP and the PNSEP, and to i nvestigate the relationship between the intraspinal and intracranial conduc tion time in the SEP pathway. The SEPs following stimulation of the posteri or tibial nerve at the ankle and the pudendal nerve at the shaft of the pen is were analyzed in 20 normal male subjects. The central conduction of the PNSEP was found to be slower than that of the PTSEP (p <0.05). This differe nce is due to a delay in conduction rather than that of intracranial conduc tion.