Digital nerve somatosensory evoked potentials and MRI. Correlation analysis in patients with symptomatic cervical spine disorders.

OBJECTIVES

Analysis of the relationship between the symptoms, digital nerve somatosensory evoked potentials (D-SEP) and MRI, in patients with symptomatic cervical spine disorders (CSD).

MATERIALS AND

METHODS

MRI and D-SEP following electrical stimulation of digits I, III and V in 44 patients.

RESULTS

Symptoms in the fingers correlated significantly with disk herniation at the corresponding cervical level and with spinal cord impingement at one or two adjacent rostral segments on MRI. D-SEP was abnormal in 52% of all patients. Among them, the groups with multiple and single level involved on MRI had 62% and 30% of abnormal somatosensory evoked potentials (SEP), respectively. Digit I-SEP abnormality was more often localized at the root level, while digit V-SEP at the spinal cord level above the dorsal nucleus. D-SEP correlated best with compression of the spinal cord at adjacent upper and especially the most rostral (C3-5) levels on MRI.

CONCLUSIONS

Accurate correlation of D-SEP and symptoms with MRI is essential for correct localization of lesions in patients with CSD.