The spinal SEPs can be used to evaluate conduction along the somatosensory pathway and, in particular, the transit time from the arrival at the spinal cord to the initiation of the cortical potentials.

In this study, we have recorded cervical spinal evoked potentials over the upper, middle, and lower cervical spine and the scalp in normal adults using the median, ulnar, and musculocutaneous nerve stimulation.

The latencies and the amplitudes of spinal evoked potentials over the upper, middle, and lower cervical spine are 12.92±0.93msec & 1.19±0.58μV, 12.86±0.86msec & 1.18±0.44μV,12.86±0.80msec & 1.21±0.50μV for the median nerve, 13.63±1.33msec & 0.71±0.26μV, 13.53±1.17msec & 0.86±0.43μV, 13.51±1.13msec & 0.90±0.49μV for the ulnar nerve, and 12.41±1.10msec & 0.88±0.30μV, 12.37±1.06msec & 0.97±0.43μV, 12.36±1.08msec & 1.02±0.49μV for the musculocutaneous nerve. We established average values for the cervical spinal evoked potentials in normal Korean adults, and these will be a data base for the further studies about it.

There are no statistically significant differences in the latency and amplitude of cervical evoked potentials between the upper, middle, and lower levels.