Central somatosensory conduction in normal Nigerians and patients with spinal cord disorders

ABSTRACT

Spinal and scalp somatosensory evoked potentials obtained by tibial nerve stimulation were recorded in 24 normal adult Nigerians and 11 patients with non-traumatic spinal cord disorders. The morphology and means of latencies of the major somatosensory evoked potential (SEP) components in the normal subjects (N21 22.6 + 1.4 msec; P40 39.1 + 2.5 msec; N50 48.3 + 2.3 msec and P60 62.4 + 3.9 msec) were similar to those reported in other populations. Seven of the 11 patients had abnormal central somatosensory conduction (CSC) as judged by a weighted scoring scheme. This was abnormal in all four patients with impaired proprioception and in three of seven patients with normal proprioception. This preliminary report shows that SEP studies are useful in detecting sub-clinical posterior column dysfunction in Nigerian patients with spinal cord disorders and the severity of this could be graded with the CSC scoring scheme