Platform Session – Electromyography: Evaluation of motor fiber functions at an early stage of diabetic peripheral neuropathy

Introduction To evaluate the functions of the myelin and axons of motor fibers during the early stages of diabetic peripheral neuropathy (DPN), using single-fiber conduction study (SF-CS) and motor unit number estimation (MUNE). Methods Eighty patients with type 2 diabetes mellitus were divided into three groups according to the results of common peroneal nerve conduction study (NCS): the DM normal group (normal sensory and motor conduction); DM abnormal sensation group (abnormal sensory conduction); and DM mixed abnormal group (abnormal sensory and motor conduction). The control group was from the general population. The common peroneal nerve SF-CS and MUNE of the extensor digitorum brevis were performed in all subjects. Correlations between SF-CS and MUNE results and DM duration, fasting plasma glucose levels and glycosylated hemoglobin A1c (HbA1c) levels were evaluated. Results No significant difference was observed in the single-fiber conduction velocity (SF-CV), single-fiber distal motor latency (SF-DML) or MUNE between the DM normal and the control group. In the DM abnormal sensation group, the SF-CV and MUNE were significantly lower (P  Conclusion SF-CV and MUNE detected motor nerve dysfunction in patients with DM much earlier than conventional nerve conduction studies.