Percutaneous Electrical Nerve Stimulation: A novel analgesic therapy for diabetic neuropathic pain

Compared with the pain VAS scores before active (6.2 ± 1.0) and sham (6.4 ± 0.9) treatments, pain scores after treatment were reduced to 2.5 ± 0.8 and 6.3 ± 1.1, respectively.
60% reduction in pain noted with TENS.
Active PENS treatments produced significant pain relief, increased levels of mood and physical activity, and improved quality of sleep compared with the sham treatments during the course of the 3-week treatment period.
Although the precise mechanism of PENS-induced analgesia is not known at this time, it appears to be related to both neural modulation and an increase in endogenous opioid-like substances (e.g., dynorphins, endorphins, enkephalins) within the central nervous system.
Interestingly, both Cameron et al. and Mo et al. have reported that peripheral electrical stimulation can normalize the changes in nerve conduction velocity when using an experimental diabetic rat model.
Walsh et al. also observed a decrease in nerve conduction latency and mechanical pain threshold when TENS was applied directly over the nerve.
In addition, clinical studies have suggested that the use of electrotherapy in diabetic patients produces decreases in mechanical pain threshold, a local vasodilatory effect, and enhanced wound healing.