Electrophysiological contribution of both sensory branches of the superficial peroneal nerve in the diagnosis of peripheral neuropathy.

The aim of this study is to evaluate the simultaneous recording of the medial dorsal cutaneous nerve (MDCN) and the intermediate dorsal cutaneous nerve (IDCN) in the investigation of peripheral neuropathy. We obtained MDCN and IDCN recordings in 35 patients with peripheral neuropathy and in 41 healthy subjects to determine the specificity of the sensory nerve action potential (SNAP) amplitude of each branch separately and of both simultaneously by using the maximal amplitude of either branch. The patients with peripheral neuropathy had low MDCN and IDCN SNAP amplitude in 60% and 14.3% respectively. Though, when recording both MDCN and IDCN simultaneously, the maximum peroneal SNAP amplitude was abnormally low in 68.6%. All the healthy individuals had normal IDCN SNAP amplitude; whereas in 9.7% the MDCN SNAP amplitude was lower than normal. In case of simultaneous recording of both branches the maximum SNAP amplitude was normal in all healthy subjects. Conclusively, the simultaneous amplitude recording of the terminal sensory peroneal branches can better detect abnormal responses in patients with peripheral neuropathy.