Decreasing pain in electrical nerve stimulation.
OBJECTIVE: Do large stimulation electrodes reduce pain in nerve conduction testing? METHODS: Fourteen healthy subjects (6 men, 22-42 years) blinded for study design underwent 8 H-reflex studies, using a large (36 x 36 mm) or a small (6 x 6 mm) electrode, placed on either the patella or the popliteal fossa; either site could be used for the cathode or the anode. Stimulation intensity was adjusted to obtain M- and H-waves. Intensity and other characteristics of pain were noted, as were M- and H-wave parameters. RESULTS: Pain was felt strongest near the smaller electrode when two sizes were used. Large electrodes reduced pain without compromising H- or M-waves. CONCLUSIONS: Large stimulation electrodes reduce pain. SIGNIFICANCE: The results apply for tests relying on amplitude measurements.