Radial Extracorporeal Shock Wave Therapy in Knee Osteoarthritis: A Meta-Analysis and Meta-regression of Randomized Controlled Trials
C.L. Lopes, A.V.S.L. Lopes, F.T. De SouzaObjective:
To evaluate the efficacy of radial extracorporeal shock wave therapy (rESWT) for pain and functional limitation in adults with knee osteoarthritis (KOA).
Methods:
A systematic review and meta-analysis were conducted following PRISMA 2020 and registered in PROSPERO (CRD420251084852). Randomized controlled trials comparing rESWT with sham, no intervention, or other conservative treatments were identified through PubMed (MEDLINE), Embase, and Cochrane Library (last search August 2025). Two reviewers independently screened studies, extracted data, and assessed risk of bias using the Cochrane RoB 2.0 tool. Random-effects models were applied for continuous outcomes (mean difference [MD] with 95% CI). Heterogeneity was assessed with I², and meta-regression explored the effect of energy level and number of sessions.
Results:
Fourteen RCTs involving 968 participants with symptomatic KOA were included. Compared with controls, rESWT significantly reduced pain (VAS MD = -1.50; 95% CI = -2.21, -0.78; P < 0.0001; I2 = 94%) and improved function (WOMAC MD = -8.11; 95% CI = -13.72, -2.50; P = 0.005; I2 = 94%). Effects remained evident at 3 months in studies with extended follow-up. Meta-regression indicated that protocols using moderate energy densities (≈ 1.5–2.5 bar; 0.10–0.25 mJ/mm²) and ≥ 4 sessions yielded greater improvements in WOMAC function (p < 0.05). No serious adverse events occurred; transient local discomfort was the most common reaction.
Conclusions:
rESWT provides clinically relevant short-term improvements in pain and physical function with minimal adverse effects in KOA. Treatment effectiveness appears dose-dependent, supporting moderate-intensity, multi-session protocols as optimal regimens.