Adjunctive electrophysical therapies used in addition to land-based exercise therapy for osteoarthritis of the hip or knee: A systematic review and meta-analysis

Objectives: To review evidence for effectiveness of electrophysical therapies (EPTs), used adjunctively with land-based exercise therapy, for hip or knee osteoarthritis (OA), compared with 1) placebo EPTs delivered with land-based exercise therapy or 2) land-based exercise therapy only. Methods: Six databases were searched up to October 2023 for randomised controlled trials (RCTs)/quasi-RCTs comparing adjunctive EPTs alongside land-based exercise therapy versus 1) placebo EPTs alongside land-based exercise, or 2) land-based exercise in hip or knee OA. Outcomes included pain, function, quality of life, global assessment and adverse events. Risk of bias and overall certainty of evidence were assessed. We back-translated significant Standardised Mean Differences (SMDs) to common scales: 2 points/15% on a 0–10 Numerical Pain Rating Scale and 6 points/15% on the WOMAC physical function subscale. Results: Forty studies (2831 patients) evaluated nine different EPTs for knee OA. Medium-term effects (up to 6 months) were evaluated in seven trials, and one evaluated long-term effects (>6 months). Adverse events were reported in one trial. Adjunctive laser therapy may confer short-term effects on pain (SMD -0.68, 95%CI -1.03 to -0.34; mean difference (MD) 1.18 points (95% CI -1.78 to -0.59) and physical function (SMD -0.60, 95%CI -0.88 to -0.34; MD 12.95 (95%CI -20.05 to -5.86)) compared to placebo EPTs, based on very low-certainty evidence. No other EPTs (TENS, interferential, heat, shockwave, shortwave, ultrasound, EMG biofeedback, NMES) showed clinically significant effects compared to placebo/exercise, or exercise only. Conclusions: Very low-certainty evidence supports laser therapy used adjunctively with exercise for short-term improvement in pain and function. No other EPTs demonstrated clinically meaningful effects.