Combined transcutaneous electrical nerve stimulation and low-level laser photobiomodulation for postoperative pain after cesarean section: A randomized controlled trial.

INTRODUCTION

Postoperative pain after cesarean section may delay recovery and impair function. Transcutaneous electrical nerve stimulation (TENS) and low-level laser photobiomodulation (PBM) are used for pain control, but the additional effect of combining these therapies remains unclear. This study investigated this effect.

METHODS

A randomized clinical trial with four groups: combined TENS + low-level laser photobiomodulation (PBM), TENS alone, placebo, and control. Assessments were performed at 8-12 h (t1), 20-24 h (t2), and 44-48 h postpartum (t3). Outcomes included pain intensity, functional independence, functional capacity assessed by the Two-Minute Walk Test (2MWT), and cardiorespiratory variables. Two intervention sessions were applied after t1 and t2, except in the control group. Data were analyzed using mixed ANOVA and nonparametric equivalents when appropriate. Statistical significance was set at p < 0.05.

RESULTS

A total of 88 women were included. Pain intensity decreased significantly over time in the combined TENS + PBM group (1.82 ± 1.18 at t2 vs 1.30 ± 0.86 at t3; p = 0.008) and in the TENS group (1.59 ± 1.05 at t2 vs 0.95 ± 1.05 at t3; p = 0.025). Functional independence increased in the combined therapy group (14.9 ± 3.3 at t1 vs 17.1 ± 3.6 at t3; p = 0.034) and in the TENS group (15.2 ± 3.0 at t1 vs 17.5 ± 3.4 at t3; p = 0.028). Functional capacity improved in all groups between t2 and t3 in the Two-Minute Walk Test (Control: 63.5 vs 76.8 m, p = 0.002; Placebo: 50.3 vs 63.9 m, p = 0.002; Combined: 48.3 vs 65.2 m, p = 0.0006; TENS: 61.1 vs 72.2 m, p = 0.005). No significant differences were observed between groups (p > 0.05). A significant time effect was found for pain (p < 0.05) and functional independence (p < 0.001).

CONCLUSION

Pain decreased and functional independence improved during the postoperative period. However, the combination of TENS and low-level laser photobiomodulation did not provide additional benefits compared with the other groups.