OBJECTIVE: Back pain is one of the most common complaints in the emergency department (ED). Since current pharmacological treatments for back pain are often suboptimal, a multimodal approach that includes nonpharmacological modalities has promise to improve pain management. The objective of the current study was to test the hypothesis that transcutaneous electrical nerve stimulation (TENS) would be more effective at relieving back pain than sham TENS.
METHODS: We conducted a patient- and observer-blinded, randomized controlled trial that included adult (=18 years) ED patients with lumbar or thoracic back pain of at least moderate pain severity. Participants were randomly assigned (1:1) to TENS or sham TENS. The primary outcome was absolute reduction in pain severity at 30 min after treatment measured with a verbal numeric scale from 0 to 10 (none to worst). A sample of 80 patients had 80% power to detect a 1.5-point between-group difference in pain severity. The trial was registered with ClinicalTrials.gov (NCT04227067).
RESULTS: We enrolled 80 subjects (40 to the TENS group, 40 to the sham group). Mean (±SD) age was 46 (±16) years, and 51% were female. Mean (±SD) pain scores before and after treatment were 8.4 (±1.6) and 6.8 (±2.4) in patients treated with TENS. Mean (±SD) pain scores before and after treatment were 8.0 (±1.7) and 7.5 (±2.1) in patients treated with sham TENS. The mean (±SD) reduction in pain score was significantly greater in TENS versus sham patients, 1.7 (±2.0) versus 0.5 (±1.0; p = 0.002). Rescue medication was administered to fewer patients treated with TENS than with sham (45% vs. 73%, p = 0.02) and patient satisfaction was higher in the TENS than in the sham group (78% vs. 50%, p = 0.02).
CONCLUSIONS: TENS was more effective than sham TENS at reducing pain severity in adult ED patients with back pain.
| Discipline Area | Score |
|---|---|
| Physician |  |
Physician rater
Small sample size.
Physician rater
TENS has been shown to have potential to relieve acute back pain in emergency settings. However, the authors in the "Limitations" section acknowledge the sub-optimal methodological quality of the trial, which reduces the certainty of the conclusions. Further multicentre studies with larger sample sizes and longer follow-up periods are required to confirm the efficacy and broader applicability of these preliminary results.
Physician rater
This study is highly relevant. Many hospitals advocate being pain free and most of the time the oral/parental routes of analgesia are used. TENS has mostly been used in rehab/sports medicine/physiotherapy sessions, but not as a choice of analgesia in Emergency Depts. This is worth exploring.
Physician rater
This is a decently good RCT, however, I do agree with the limitations discussed. Given that a large number of people in the sham group were able to guess which group they were in may have affected results.
Prof. Mike Poling (4/13/2025 7:07 AM)
Sham TENS? How was this done? You would still have to provide some sort of electrical stimulus which may still have a clinical effect. TENS can be placed anywhere and still be effective. So how was sham TENS provided without introducing a clinical effect?
, McMaster University