A Study of F Wave Latencies, Chronodispersion and Persistence in Healthy Medical Undergraduates at BPKIHS

Background The F wave is a CMAP (compound muscle action potential) evoked by a supramaximal stimulation of a motor nerve. F waves are particularly useful for the diagnoses of polyneuropathies at a very early stage and proximal nerve lesions. F waves have a very high diagnostic role in neurophysiology; we would like to study different F wave parameters and effect of anthropometric variables on F wave parameters in normal healthy individuals. Objective To study the effect of anthropometric variables on F wave latencies, chronodispersion and persistence Method Healthy males (n=64) and females (n=26) medical students of BPKIHS with age 21.64±1.19 years were enrolled in the study. Anthropometric parameters and maximum and minimum F wave latencies, F persistence and chronodispersion of bilateral median, ulnar and tibial nerves were recorded in Neurophysiology Lab II of BPKIHS. Descriptive analysis was done for anthropometric and F wave parameters. Unpaired t test was applied for comparing anthropometric and F wave variables between males and females. Pearson correlation was applied between anthropometric variables and F wave parameters. Result Age, height and weight of the subjects were 21.64±1.19 years, 165.61±5.4 cms and 64.07±5.5 kg respectively. Minimum F wave latencies (ms) of right median, ulnar and tibial nerves were 24.09±1.95, 24.02±1.76 and 44.34±3.02 while on the left side were 23.92±1.96, 24.11±1.92 and 44.07±2.83 respectively. Anthropometric variables of male and females were statistically significant. Also, F wave latencies between groups were different which were statistically significant. F persistence was above 80% for all tested peripheral nerves. Height and weight showed a significant effect on F wave latencies (p<0.001). However, age did not show any significant effect on F wave parameters. Conclusion Males have prolonged latencies as compared to females. Height and weight showed a significant relationship with the F wave latencies of the tested peripheral nerves.