A systematic review and meta-analysis of the effect of phonophoresis on patients with knee osteoarthritis

Yang FA, Chen HL, Peng CW, Liou TH, Escorpizo R, Chen HC · Scientific Reports

Pain improved with an NSAID gel (SMD -0.53, 95% CI -1.02 to -0.05, I2 73%) and WOMAC function with a corticosteroid gel (SMD -0.96, 95% CI -1.47 to -0.44, I2 20%). Overall risk of bias was low in three of the nine trials and uncertain in six. No adverse event was reported. Nothing structural was measured.

Population

Patients with knee osteoarthritis in nine randomised trials, searched to June 2021 with no language restriction

Intervention

Phonophoresis — the same ultrasound head used to drive a drug through the skin, with an NSAID, corticosteroid or herbal gel

Comparator

The same therapeutic ultrasound with a placebo gel containing no drug, so the comparison isolates the drug rather than the sound

Limitations

Author-reported: heterogeneity moderate to high on some outcomes, short follow-up throughout, blinding unstated in some trials, and the NSAID pain result moved when single studies were removed in the sensitivity analysis, which the authors say may compromise its stability. Both arms received ultrasound, so this measures what the gel adds and not what the ultrasound does. No specific grant funding; the authors declare no competing interests.