Randomized Double-Blind Sham-Controlled Crossover Study of Short-Term Effect of Percutaneous Electrical Nerve Stimulation in Neuropathic Pain
Pain Medicine, 08/24/2011
Raphael JH et al. – Percutaneous electrical nerve stimulation (PENS) therapy appears to be effective in providing short–term pain relief in chronic pain conditions. Studies, involving larger sample sizes and longer follow–up are recommended.
Methods- A randomized double–blind sham–controlled crossover trial.
- 31 patients with chronic pain with surface hyperalgesia to investigate the efficacy of PENS.
- For the active PENS therapies, the median numerical rating scale (NRS) for pain changed from 7.5 (standard deviation [SD] ± 1) (range 6–10) before therapy to 0.5 (range 0–8.5) after therapy (Z = –4.206, P < 0.0005 [two–tailed]).
- The mean pain pressure threshold (PPT) measured with the von Frey aesthesiometer changed from 202 gm (SD ± 137 gm) (range 55–800 gm) before therapy to 626 gm (SD ± 228 gm) (range 45–800 gm) after therapy (Z = –4.373, P < 0.0005 [two–tailed]).
- There was a statistically significant difference between the changes in NRS for the active (3.9 [±3.2][0–8]) compared with the sham (0.1 [±0.4][0–1.5]) therapies, U = 40, Z = –3.484, P < 0.0001 (two–tailed).
- There was a statistically significant difference between the changes in PPT for the active (310 gm [±267 gm][0–670 gm]) compared with the sham (8 gm [±4 gm][0–15 gm]) therapies, U = 48.5, Z = –2.699, P = 0.007 (two–tailed).
