Reference voluntary jitter values using disposable monopolar needle electrodes in the extensor digitorum communis muscle.

OBJECTIVE: To measure normal variability in neuromuscular transmission in the extensor digitorum communis (EDC) muscle voluntarily activated using a disposable monopolar needle electrode (MNPE).

METHODS: We examined the EDC muscle using MNPE in 50 healthy volunteers (12 male and 38 female, mean age: 41.5+/-12.9 years, age range: 18-74 years). The high-pass filter setting was 3 kHz.

RESULTS: Jitter values are expressed as the mean consecutive difference (MCD) of 20 potential pairs. Mean MCD (n=50) was 21.3+/-3 micros (upper 95% confidence limit (CL): 27.3 micros). Mean MCD in all potential pairs (n=1000) was 21.3+/-6.6 micros (upper 95% CL: 34 micros). Mean MCD for the 18th highest value was 28+/-4.7 micros (upper 95% CL: 37.5 micros).

CONCLUSION: The suggested practical upper limit for mean MCD was set to 28 micros; for outliers it was 38 micros.

SIGNIFICANCE: The present study defines the normative value for jitter recorded with disposable MNPE, which is a low-cost alternative for the evaluation of neuromuscular transmission, although certain precautions must be taken.