Electromyography and MRI in the Diagnosis of Brachial Plexus Injury

To evaluate the value of electromyography (EMG), MRI and the combination of the two in diagnosis of brachial plexus injury. EMG and MRI of 27 cases were examined before operation and some of the cases were examined with EMG during the process of operation The results were compared with the findings of surgery And the usefulness of EMG, MRI in the diagnosis of complete injury of brachial plexus before operation was compared with that of somatosensory evoked potential (SEP) during surgery EMG before surgery could diagnose brachial plexus with total accurate rate of 70 4% and partial accurate rate of 96 3% The accurate rates of EMG and MRI in the diagnosis of tearing of nerve roots of brachial plexus before surgery were 55 6% and 68 5% respectively, and the combination of the two could increase the rate to 85 2% SEP had higher accurate rate than EMG and MRI in the diagnosis of complete injury of brachial plexus, but the difference was not significant.[Conclusion] The combination of EMG and MRI can improve the accurate rate of diagnosis. It is a promising adjuvant method for making diagnosis of brachial plexus injury and guiding treatment. SEP during operation is helpful in choosing approaches of surgery.