Single-Blinded, Randomized Preliminary Study Evaluating the Effect of Transcutaneous Electrical Nerve Stimulation on Postoperative Pain in Patients with Colles' Fracture

Objective: Transcutaneous electrical nerve stimulation (TENS) has been widely used for pain relief; however, the effect remains controversial. The authors hypothesized that TENS can relieve acute pain. Therefore, a single-blinded, randomized, controlled preliminary study was designed on postoperative pain in patients with Colles' fracture. Methods: In total, 36 patients were assigned to a real TENS or sham TENS group (18 patients in each group). TENS (50Hz, 15min/day) was applied near the Quchi (LI11) and Waiguan (TE5) surfaces of the operative side continuously for 5 days after surgical treatment. Results: The visual analog scale (VAS) scores did not differ significantly between the real and sham TENS groups before the TENS period, from the first to fifth day after surgical treatment (all p>0.05), whereas the VAS scores were lower for the real TENS group than for the sham TENS group in the post-TENS period, on the first, third, fourth, and fifth days after surgical treatment (all p0.01). Conclusion: TENS might be valuable as a treatment of postoperative pain, but clinicians and researchers should know that it is no different than a treatment with placebo. Especially, since this form of treatment and sham treatment has a great chance of working under the mechanism of the placebo effect due to its single-blindedness.