Combined application of multiple electrophysiological examinations for diagnosis of root injuries of the brachial plexus

Objective To investigate the value of combined use of multiple electrophysiological examinations in the diagnosis of brachial plexus root injuries. Methods 200 cases of brachial plexus root injuries were reviewed about the preoperative electrophysiologic diagnosis and the surgical findings. 82 cases were treated before 1997. Preoperative examinations included electromyogram(EMG), compound muscle action potential(CMAP) of the muscles of shoulder girdle and the representing muscles of the five major nerves in the upper extremity, motor nerve conducting velocity(MNCV), sensory nerve action potential(SNAP), sensory nerve conducting velocity(SNCV), and somatosensory evoked potential(SEP). EMG of cervical paraspinal muscles, CMAP of bilateral diaphragms, and EMG and CMAP of trapezius muscle were also tested in addition to the above mentioned examinations for the 118 cases treated since 1997. Results According to intraoperative exploration, the completely correct diagnostic rate of electrophysiologic examination was 80Electrophysiologic examination of cervical paraspinal muscles and the functional assessment of phrenic nerve and accessory nerve could raise the diagnostic rate of brachial plexus root injuries, in particular postganglionic lesion of C 5 nerve root.