Extracorporeal Shock Wave Therapy Versus Local Corticosteroid Injection for Chronic Lateral Epicondylitis: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

Chronic lateral epicondylitis (LE), normally known as tennis elbow, is often managed by conservative treatments. Extracorporeal shock wave therapy (ESWT) and local corticosteroid injection (LCI) are among the most commonly used conservative treatments. However, the comparison between these two interventions remains controversial. This study aimed to compare the effectiveness and safety of ESWT and LCI for chronic LE. A systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. PubMed, EMBASE, Cochrane Library, and Web of Science were searched for eligible studies until April 20, 2024. Meta-analyses were conducted using Manager V.5.4.1. Pooled effect sizes were expressed as the weighted mean difference (WMD) or odds ratio (OR), with 95% confidence intervals (CIs). A total of six randomized controlled trials (RCTs) were included. Compared with LCI, ESWT had inferior change in visual analogue scale (Delta VAS) (WMD, 1.14; 95% CI, 0.80 to 1.48; I-2 = 20%; p < 0.001), Delta grip strength (WMD, -4.01; 95% CI, -5.57 to -2.44; I-2 = 36%; p < 0.001), change in patient-rated tennis elbow evaluation (Delta PRTEE) score (WMD, 8.64; 95% CI, 4.70 to 12.58; I-2 = 0%; p < 0.001) at 1-month follow-up, but superior Delta VAS (WMD, -1.15; 95% CI, -1.51 to -0.80; I-2 = 6%; p < 0.001), Delta grip strength (WMD, 2.04; 95% CI, 0.90 to 3.18; I-2 = 3%; p = 0.0005), Delta PRTEE score (WMD, -9.50; 95% CI, -14.05 to -4.95; I-2 = 58%; p < 0.001) at 3-month follow-up, and superior Delta VAS (WMD, -1.81; 95% CI, -2.52 to -1.10; I-2 = 33%; p < 0.001), Delta grip strength (WMD, 3.06; 95% CI, 0.90 to 5.21; I-2 = 0%; p = 0.005) at 6-month follow-up. The two groups had a similarly low rate of adverse events (OR, 0.69; 95% CI, 0.05 to 8.60; I-2 = 67%; p = 0.77), all of which were mild. Both ESWT and LCI are effective and safe in treating chronic LE. Compared with LCI, ESWT showed inferior short-term (1-month) but superior long-term (3-month and 6-month) outcomes regarding pain relief and function recovery, with a similar rate of mild adverse events.