Application of electromyography combined with magnetic resonance imaging in the diagnosis of brachial plexus injury in newborns

Objective To investigate the characteristics of electromyography(EMG) and MRI in the diagnosis of brachial plexus injury in newborns. Methods First, the EMG examination was conducted in 30 newborns with brachial plexus injury, where the brachial plexus of the five major nerve conduction and muscle EMG activity were measured.Second, the brachial plexus MRI was conducted to compare with the first examination. Results EMG revealed that 25 cases of upper and middle trunk palsy(83.3%), 4 cases of total plexus palsy(13.3%) and 1 case of lower trunk palsy(3.3%) in the 30 cases, as well as 6 cases of plexus pre-ganglionic injury(20.0%), 7 cases of complete injury(23.3%), 23 cases of incomplete injury(76.7%). MRI showed that 5 cases of upper and middle trunk palsy(16.7%), 1 case of total plexus palsy(3.3%), 1 case of lower trunk palsy(3.3%), and 7 cases of plexus pre-ganglionic injury(23.3%)in the whole 30 cases. Conclusion EMG and MRI are both helpful to localize the brachial plexus injury.But EMG performs better compared with MRI towards the slight incomplete injury.Therefore, the combination of both methods can provide an accurate guidance for diagnosis. Key words: Newborn; Brachial plexus injury; Electromyography; Magnetic resonance imaging