Analysis Of Electromyogram Of Acute Flaccid Paralysis In Children's Hand-foot-mouth Disease

Objective:To study the characteristics of electromyogram in the children with acute flaccid paralysis(AFP) caused by hand-foot-mouth disease(HFMD). To analyse the characteristics of electroneurogram and needle electromyogram of AFP caused by HFMD, in order to understanding the relationship between the abnormal manifestations of electroneurogram and needle electromyogram and the common central nervous system infections of the children with HFMD such as viral encephalitis, brain stem encephalitis and encephalomyelitis etc. To explore the application value of EMG in the diagnosis, treatment and rehabilitation of the children with HFMD.Methods:The apparatus we used is the Keypoint-W 4-channel EMG instrument that was made in Danmark. The operation parameters are band-pass/2-10kHz, stimulating time/0.2ms, stimulation frequency/1 Hz, and the stimulating intensity is powerful stimulus. The room temperature is 24℃to 26℃and the skin temperature is 30℃to 32℃. From May 2008 to August 2011, conventional electroneurogram and needle electromyogram have been performed to study abnormalities in 157 children with AFP caused by HFMD. To analyse abnormalities and characteristics of the electroneurogram and needle electromyogram. Electromyogram measurements were carried out on children respectively, according to different clinical manifestations. The items are as follows:motor never conduction velocity(MCV), sensory never conduction velocity(SCV), femoral nerve motor latency(FML) and concentric needle electromyogram. We used the disposable adhesive surface electrodes as the recording electrode, and the saddle-shaped electrode as stimulating electrodes in the determination of MCV, FML and SCV of superficial. The ring electrodes are used as stimulating electrodes in all the determination of SCV, and the disposable adhesive surface electrodes as stimulating electrodes, in addition to the SCV of superficial peroneal nerve. Abnormal standard is:more than twice the standard deviation of normal, or clear differences between the uninjured side and affected side. We analysed the types and characteristics of abnormal manifestation of electroneurogram and needle electromyogram in children with AFP caused by HFMD. Comparison and analysis were made among the electroneurogram and needle electromyogram results from different CNS infection childrenResults:Among 157 cases of AFP caused by HFMD,105 cases were male,52 cases were female. Of the children tested,66.88% were male, with a remarkable proportional difference between the male and female. The result showed that the electromyography abnormalities in the cases were 64.33%(101/157). Of the total 157 cases of AFT, lesions affected limbs in 12 cases (7.64%), upper limb 11 cases (7.01%), lower limb 134 cases (85.35%), and the abnormal rates were 58.33%, 100%and 61.94%. In this group, the electromyogram abnormalities in the non-central system infection group, viral encephalitis group, brainstem encephalitis group and encephalomyelitis group were 75%(12/16),56.44%(57 /101),70%(14/20)and 100%(18/18) respectively. According to the involved area, corresponding examination was given to each groups. A total of 1094 motor nerves,718 sensory nerves and 685 muscles were measured, and the results were analysed. The common findings were that the amplitude of the compound muscle action potential(CMAP) reduced. Prolongation of the distal latency and slight reduction of MCV was found in individuals. All of SCV tests came back with normal results. The main abnormalities of concentric needle electromyogram was that the recruitment potential reduced. Detection of KMG displayed that duration of MUP was prologed, amplitude of MUP was increased and spontaneous potential appeared in part of the cases in this report. Conclusion:The results showed obviously that more males than females were affected in AFP caused by HFMD. Most children showed flaccid paralysis of lower limbs, and that the number of children showed flaccid paralysis of upper limb or limbs was less. In the 157 cases, there was no significant difference among the abnormal rates of electromyogram of the children with viral encephalitis or brain stem encephalitis and the children without CNS infection. The abnormal rate of children with encephalomyelitis were higher than others. The main parts of the lesions involving the motor neurons of cornu anterius medullae spinalis, and axonal degeneration was the main types of neuropathy.