Median nerve F-wave latencies recorded from the abductor pollicis brevis

This study was performed to create a normative database for median nerve F-wave responses for a large subject population so normal ranges could be created for subsets of the general population and the effect of various physical characteristics on F-wave results could be determined. One hundred ninety-five asymptomatic subjects without risk factors for neuropathy were recruited. Ten consecutive supramaximal stimuli were applied to the wrists of each arm to obtain median nerve F-wave results. The shortest F-wave latency (F-min), mean latency (F-mean), range of latencies (F-range) and number of stimuli that resulted in F-wave recordings (F-persist) were recorded. An analysis of variance revealed that age, gender, and height were associated with different results for F-min and F-mean. For all subjects taken together, the mean F-min was 26.8 +/- 2.4 ms. The mean F-mean was 28.3 +/- 2.6 ms, and the mean F-range was 3.4 +/- 1.9 ms. Five or more F-waves were elicited in 94% of the subjects. The mean side-to-side difference in F-min was 0.2 +/- 1.2 ms. Additional findings are presented in the article.