Proximal Sensory Nerve Conduction Velocity Is Correlated With Conduction Time of H-Reflex in Healthy Individuals
Introduction: Nerve conduction velocity is the typical clinical examination of nerves function for people with peripheral neuropathy, but a measure of only a segment of a reflexive arc. H-index, as the time course measurement of the H-reflex, is influenced by the conduction times of both sensory and motor nerves involved, as well as the central delay in the spinal cord. Therefore, H-index would provide a more comprehensive picture of a spinal reflexive arc. However, there is no report in regarding the relationship between nerve conduction velocity and H-index.
Purpose: This study was aimed at the understanding of the relationship between H-index, outcomes of H-reflex, and nerve conduction velocity in healthy elderly adults.
Methods: Six participants (1 male, 5 female) were recruited. Body mass, height and age were recorded. Skin temperature was above 31°C before testing. H-reflex was tested at the soleus muscle (Zhang, Holmes, & Li, 2014); proximal sural nerve conduction velocity was tested to represent sensory nerve conduction velocity (SCV) (Burke, Skuse, & Lethlean, 1974); and tibial nerve conduction velocity was tested as a representation of the motor nerve conduction velocity (MCV) (Buschbacher, 1999). The H-index, Hpeak, Mpeak, H/M ratio (ratio of Hpeak / Mpeak), SCV and MCV were recorded and pooled into Pearson correlation test.
Results: The average age (71 ± 8 years old), height (163 ± 8 cm), body mass (82 ± 25 kg), H-index (76 ± 17), Mpeak (4 ± 2 mv), Hpeak (1.0 ± 0.7 mv), H/M ration (0.3 ± 0.2), SCV (23 ± 3 m/s) and MCV (29 ± 2 m/s) were observed. Significant positive correlations were observed between H-index and SCV (r = .8) as well as Mpeak (r = .8). Significant negative correlation was observed between H-index and H/M ratio (r = -.7). No other significant correlation was observed between H-index and MCV as well as Hpeak.
Conclusions: Conduction time of sensory nerve is an influential component of H-index. The faster conduction time of the H-reflex loop, the less H/M ratio due to increased Mpeak.
American College of Sports Medicine Annual Conference (ACSM)
San Diego, CA
Zhang, Shuqi, Li Li.
"Proximal Sensory Nerve Conduction Velocity Is Correlated With Conduction Time of H-Reflex in Healthy Individuals."
Health and Kinesiology Faculty Presentations.