Evaluation of an External Vibrating and Cold Device on Patient Pain Perception During Needle Electromyography.

Introduction/aims: Previously tested interventions to reduce pain with needle electromyography (EMG) reported limited benefit. A topical cold and vibrating device has reported benefit in interventional procedures. We aimed to evaluate the effect of this device with EMG.

Methods: This was a two-part, prospective controlled study of a cold and vibrating device. In part one, 50 patients undergoing EMG testing on the upper extremity were randomized to EMG with or without the device and reported pain scores for each muscle. In the second part, 25 patients having EMG of both upper extremities reported pain scores, one side with the device and the other without.

Results: In part one, there was no significant difference in average pain scores for patients with use of the device as compared to those without (average pain score 4.1 versus 3.7, p = 0.61). In the second part, there was no significant difference in pain scores in muscles tested with the device as compared those without (average pain score 4.3 versus 4.6, p = 0.47). In both parts, a wide range of pain scores were reported (0-10). In comparing device-to-control pain scores for each patient, 27% had a lower score, 15% had a higher score, and 58% had equal scores. There were no adverse events.

Discussion: This study did not show pain reducing benefits from a cold and vibrating device that have been described in other interventional procedures. This may relate to different study populations, wide range of pain scores and study sample size.