This study investigated 54 patients with cervical spondylosis (CS) with or without symptoms caused by cervical spondylotic myelopathy. Cervical MRI, somatosensory evoked potentials (SEPs) and motor evoked potentials (MEP) from upper and lower limbs of all of these patients were examined retrospectively. Were MRI findings the gold standard and the patients were classified in three groups. Group 1 (absence of spinal cord compression ); Group 2 ( presence of spinal cord indentation); Group 3 (spinal cord compression with alteration of intraspinal sign). The sensitivity of SEP of four limbs was 61.9%, the same one as the SEP of lower limbs. The sensitivity of MEP of four limbs was 71.4%, of the upper limbs alone was 66.7% and of the lower limbs alone 52.4%, thus showing the importance of using this method in all four limbs when cervical spondylotic myelopathy is suspected. The results shown by the study of the tibial nerve in SEP and of the abductor digiti minimi muscle in MEP were more frequently abnormals than the results shown by the study of the median nerve and extensor digitorum brevis muscle in the three groups, suggesting that exists a onset compromising of them.
motor evoked potentials; somatosensory evoked potentials; cervical spondylosis; spondylotic myelopathy
