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

French HP, Cunningham J, Galvin R, Almousa S · Osteoarthritis and Cartilage Open

Added to exercise and against a placebo device, only laser reached a pain effect the authors call possibly clinically important (SMD -0.60, 95% CI -0.89 to -0.31; 12 trials). Ultrasound reached statistical significance on physical function (SMD -0.52, 95% CI -0.86 to -0.17, two trials, I2 0%) and the authors judge it clinically unimportant because the interval excludes their 6-point WOMAC threshold. Against exercise alone, no modality separated from exercise on pain (overall SMD -0.08, 95% CI -0.42 to 0.26, 21 trials, I2 86%) or function (SMD -0.17, 95% CI -0.43 to 0.09). Two NMES trials found no quality-of-life difference against exercise alone (SMD -0.76, 95% CI -1.64 to 0.11). Certainty was low or very low for every ultrasound, shockwave and NMES comparison. Radiographic joint structure was not reported in any of the 40 trials.

Population

Adults with knee osteoarthritis in 40 randomised or quasi-randomised trials; no trial of hip osteoarthritis was found, so the results apply to the knee only

Intervention

Nine electrophysical therapies added to land-based exercise: laser, therapeutic ultrasound, TENS, interferential current, shortwave, shockwave, heat, EMG biofeedback and neuromuscular electrical stimulation

Comparator

The same exercise with a placebo version of the device, or the same exercise alone

Limitations

Author-reported: high or unclear risk of selection, performance, detection or attrition bias across most trials, small samples, considerable heterogeneity (I2 up to 86%), and only six trials measuring beyond the end of treatment with one beyond six months. The abstract's phrasing that no modality other than laser showed clinically significant effects is looser than the results, where ultrasound is statistically significant on function and judged below the clinical threshold. No external funding; the authors report no conflict of interest.