Features of the nervous system damage in the registration of somatosensory-evoked potentials in patients with vibration disease

Abstract

Introduction. Objective data necessary for acquiring information about the localization and severity of the pathological process in afferent conductive structures can be obtained by registering somatosensory evoked potentials (SSEP). The goal is to identify neurophysiological features during the registration of SSEPs during stimulation of the median and tibial nerves in patients with the vibrational disease (VD). Material and methods. 140 people were examined: group 1 - 50 patients with VD associated with the combined effects of local and general vibration (aged 48.7 ± 3.1 years); Group 2 - 50 patients with VD associated with exposure to local vibration (aged 48.9 ± 2.8 years); Group 3 - control, including 40 relatively healthy men without the exposure to vibration (aged 49.1 ± 2.5 years). Registration of SSEP was carried out with stimulation of the median and tibial nerves. Statistical processing of the results is “Statistica 10.0” (StatSoft, USA, 2011). The differences in the mean values in the samples were estimated using the Wilcoxon criterion. The differences were considered statistically significant at p <0.05 and 0.01. Results. When the median nerve was stimulated, the latency of the SSVP components increased: for group 1 - indices N9, N10, N11, N13, N20, P25, N30, for group 2 - components N10, N11, N13, N30. A marked increase in latency and intervals was found in group 1. When the tibial nerve was stimulated in group 1, a statistically significant increase in the latency of components N18, N22, N30, characterizing the conduction from the popliteal fossa to the lumbar and then to the cervical level of the spine was revealed. Discussion. The results of the study are consistent with data from previous studies on SSEPs with stimulation of the median nerve. For the first time, it was revealed that in patients of group 1, the registration of SSEP during stimulation of the tibial nerve gives an increase in the time of the impulse at the peripheral level in the popliteal fossa. Conclusion. The SSVP registration method expands the state of afferent pathways. Changes in the state of neurons of the central afferent conducting structures in patients of groups 1 and 2 consisted of more pronounced functional changes at the level of the cervical spinal cord and somatosensory cortex in group 1. During stimulation of the tibial nerve, a slowing down of the afferent excitation wave from the distal sections and further along the ascending paths of the spinal cord to the posterior pillars of the cervical region was noted.