DERMATOMAL SEPS - A COMPLEMENTARY STUDY IN EVALUATING PATIENTS WITH LUMBOSACRAL DISC PROLAPSE

We investigated the value of Dermatomal Somatosensory Evoked Potential s in 24 patients with unilateral radiculopathy due to lumbosacral disk prolapse. All patients had clinical signs and symptoms of disk prolap se and positive findings on neuroradiologic testing. We assessed the l atency and the amplitude of the first positive waveform of Dermatomal SEPs, as well as conducting peripheral nerve conduction studies and el ectromyography. Our studies showed a clear correlation of Dermatomal S EP abnormalities and radiculopathy in up to 83.3% of subjects studied. Use of electromyography testing provided this correlation in about 62 .5% of the same subjects. On the basis of these results, we propose th at Dermatomal SEPs have value in complementing the routine electrophys iological testing of the patients with radiculopathy and provide a sen sitive non-invasive technique for defining the level of disk prolapse. (C) 1997 Elsevier Science B.V.