Normative Values of Whole Plantar Nerve Conduction Study in Healthy Individuals

Abstract

Introduction:Whole plantar nerve conduction study (WPNCS) is the method, in which medial and lateral plantar nerves are stimulated simultaneously with appropriate surface electrodes, and compound nerve action potentials (CNAPs) are recorded with bipolar surface electrodes proximal to the flexor retinaculum. Our aim was to determine normative values of nerve conduction study results.Methods:The study included 90 healthy volunteers of both sexes aged between 18 and 60 years. To record CNAPs, a bipolar disc electrode was placed in a proximal position near the flexor retinaculum on the ankle. Medial and lateral plantar nerves were stimulated simultaneously from the anterior transverse arch of the sole.Results:The mean CNAP amplitude was 22.82 +/- 8.16 (95% confidence interval [CI]: 21.62-24.02) mu V, with a lower limit of 10.1 and a 5th percentile value of 11.69. The mean CNAP maximum nerve conduction velocity (NCV) was 58.33 +/- 5.47 (95% CI: 57.52-59.13) m/s, with a lower limit of 45.2 and a 5th percentile value of 50.0. The mean CNAP negative peak NCV was 42.95 +/- 3.67 (95% CI: 42.41-43.49) m/s, with a lower limit of 34.6 and a 5th percentile value of 37.0.Conclusion:This study represents an electrophysiology investigation to determine normative values in a large number of volunteers with a slight technical modification after the description of the WPNCS method in 2015. It is anticipated that these limit values will be employed in the future for the diagnosis of peripheral nervous system pathologies.