Effects of cooling on the amplitude of vibration-induced sensory nerve action potentials / 中华物理医学与康复杂志

ABSTRACT

Objective:To observe any effect of cooling on the amplitude of vibration-induced sensory nerve action potentials (SNAPs) in human digits.Methods:The middle fingers of 15 healthy adults were either cooled to about 22℃ using an ice pack or kept at about 32℃. A vibrator was applied to the joint connecting the middle finger and the palm vibrating with an amplitude of 2mm at a frequency of 60Hz. The amplitudes of middle finger SNAPs before, during and right after the vibration were recorded.Results:The SNAP amplitude at a given temperature was lower during vibration than before it, but it immediately returned to the pre-vibration level after the vibration ceased. The middle finger SNAP amplitudes at 22℃ were significantly higher than those at 32℃ throughout. The decrease in amplitude at 32℃ (61.7±15.1%) was significantly greater than that at 22℃ (24.1±7.0%).Conclusions:Cooling significantly reduces the effect of vibration on the amplitude of digital SNAPs. That suggests a way to protect the sensory nerves in hand-arm vibration syndrome.