TENS for Low Back Pain
TENS should be used as part of a multimodal approach for chronic low back pain, but evidence does not support its routine use as a standalone therapy for acute or subacute low back pain. 1
Chronic Low Back Pain
The American Society of Anesthesiologists recommends TENS as part of multimodal pain management for chronic back pain, with additional consideration for neck and phantom limb pain. 1 This represents the most definitive guideline-based recommendation for TENS use.
Evidence Quality and Limitations
The evidence base reveals important contradictions:
Insufficient evidence exists to determine TENS effectiveness for acute or subacute low back pain according to the 2017 American College of Physicians guidelines. 1
A 2001 Cochrane meta-analysis of 5 trials (421 patients) found no statistically significant differences between active TENS and sham-TENS for any outcome measures in chronic low back pain. 2
However, a more recent 2016 meta-analysis of 13 studies (267 patients) demonstrated a standardized mean difference of 0.844 for pain reduction, showing significant improvement with TENS. 3
Individual RCTs show mixed results: one 1990 trial found no clinically significant benefit over sham-TENS (47% vs 42% improvement, P=NS), 4 while a 1993 study showed TENS was significantly more effective than placebo for pain intensity (though not pain unpleasantness) immediately post-treatment. 5
Critical Implementation Details
When TENS is used for chronic low back pain, specific parameters matter:
Treatment duration under 5 weeks shows significant pain effects, while treatment exceeding 5 weeks does not demonstrate sustained benefit. 3
Maximal tolerable intensity with modulating frequency (2-125 Hz) should be used, not the low intensities employed in many negative trials. 6
Short-term effects are more reliable than long-term outcomes: benefits at 1 week post-treatment diminish by 3-6 months. 5
TENS must be combined with other interventions (exercise, physical therapy, medications) rather than used as monotherapy. 1, 7
Acute and Subacute Low Back Pain
Do not use TENS for acute or subacute low back pain due to insufficient evidence of effectiveness. 1 The 2017 American College of Physicians guidelines explicitly state evidence is inadequate to determine TENS effectiveness in these populations.
Practical Clinical Algorithm
For chronic low back pain patients:
Ensure failure of conventional therapies first (medications, physical therapy) before initiating TENS. 7
Conduct a trial period (2-4 weeks) with proper parameters: maximal tolerable intensity, modulating frequency 2-125 Hz, 30-60 minute sessions. 6, 7
Assess response during peak analgesic period (immediately post-treatment and at 1 week), measuring both pain intensity and functional improvement. 6, 7
Discontinue if no benefit by 5 weeks, as longer treatment durations show diminishing returns. 3
Always combine with exercise or other active interventions rather than using TENS alone. 1, 4
Common Pitfalls
Approximately one-third of patients experience mild skin irritation at electrode sites. 8
Using inadequate current intensity is a major reason for treatment failure in many studies—intensity must be maximal tolerable, not just perceptible. 6
Expecting long-term sustained benefit without ongoing multimodal treatment leads to disappointment, as effects diminish after treatment cessation. 5, 4
Relying on TENS as monotherapy contradicts guideline recommendations and research showing exercise provides superior benefit. 1, 4