The investigation of traumatic lesions of the brachial plexus by electromyography and short latency somatosensory potentials evoked by stimulation of multiple peripheral nerves.

Abstract

SUMMARY A study of 10 patients with brachial plexus trauma was performed to determine whether the diagnostic accuracy of sensory evoked potentials (SEPs) may be improved by using stimulation of multiple peripheral nerves (median, radial, musculocutaneous and ulnar peripheral nerves: median (C6-T1), radial (C6), musculocutaneous (C5), and ulnar (C8-Tl). In addition, the relative advantages of SEPs and peripheral electrophysiological studies were considered. MethodsThe median, ulnar and superficial radial nerves were stimulated at the wrist on both sides and in two patients the musculocutaneous nerve was stimulated in the forearm.Stimuli were delivered at 2Hz by a TECA constant voltage isolated nerve stimulator with a pulse duration of 0-1 ms. The stimulus intensity was adjusted to produce a small twitch in the thenar or hypothenar muscles (median and ulnar) or to be three times sensory threshold in the case of superficial radial and musculocutaneous nerves.Gold disc 9 mm recording electrodes were attached to the skin using Grass electrode paste and tape. Electrodes were placed over Erb's point, the spinous process of the second and seventh cervical vertebrae, and the contralateral somatosensory cortex. These were referred to a common mid-frontal site (Fz). Signals were amplified and averaged by a DISA (model 1500) system with the high and low pass filters set at 2 Hz and 2 kHz for the scalp responses and 20 Hz and 2 kHz for the cervical and Erb's 1014 Protected by copyright. on 11 May 2018 by guest.

Spatiotemporal integration of sensory stimuli in complex regional pain syndrome and dystonia

“…Median nerve SSEP amplitudes appeared to be larger than ulnar nerve SSEP amplitudes, a finding that was reported by others (Yiannikas et al 1983) and may be explained by that fact that the ulnar nerve, innervating fewer fingers than the median nerve, simply contains fewer sensory fibres. An alternative explanation resides in stimulus intensity: this was set on the basis of a motor response, and thresholds for sensory and motor responses might differ between the two nerves, perhaps because of different localization of sensory and motor fibres in the nerves.…”

Dermatomal Somatosensory Evoked Potentials in Brachial Plexus Injuries

“…After cleaning and lightly abrading the areas of contact, gold cup electrodes were prepared with conductive paste, and placed at the scalp at C3' and C4' (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) International System) with Fpz as the reference site. Recording surface electrodes were also placed over C2 (Cervical-2), Erb's point (supraclavicular fossa), and on the medial aspect of the upper arm in the axillary region; reference site for these areas was at the ipsilatera1 tips of the shoulders.…”

Lesão medular: estudo do potencial evocado como recurso prognóstico e comparação entre o tratamento de estimulação elétrica neuromuscular e fisioterapia convencional

“…Essa resposta tem origem nos nervos periféricos, percorrendo a medula espinhal, o tronco cerebral, em nível subcortical e o córtex sensitivo primário, na dependência do estímulo empregado e da escolha dos parâmetros para registro [2]. Sendo assim o PESS vem sendo usado como método de avaliação para registro de estímulos dos nervos desde a extremidade dos nervos na extremidade inferior até o cérebro de sujeitos normais e pacientes com patologias da medula espinhal [3][4][5][6][7][8][9][10][11][12].…”