Comparison of Extracorporeal Shock Wave Therapy and Ultrasound-Guided Shoulder Injection Therapy in Patients with Supraspinatus Tendinitis

BACKGROUND: The present study compared the clinical effect of extracorporeal shock wave therapy (ESWT) with that of ultrasound (US)-guided shoulder steroid injection therapy in patients with supraspinatus tendinitis. We hypothesized that the two treatments would show comparable results. METHODS: The inclusion criteria were age over 20 years and diagnosis of supraspinatus tendinitis using US. Ultimately, 26 patients were assigned using blocked randomization: 13 in the US-guided shoulder injection group and 13 in the ESWT group. Treatment outcomes were evaluated using the pain visual analog scale (pVAS), the American Shoulder and Elbow Society (ASES) score, and the Constant score at baseline and at 1 and 3 months after the procedure. RESULTS: At 1 month after the intervention, pVAS, ASES, and constant score were significantly higher in the US-guided shoulder injection group than in the ESWT group, but not at 3 months after the intervention. Both groups showed clinically significant treatment effects at 3 months after the intervention compared to baseline. No significance was shown using equivalence testing. CONCLUSIONS: US-guided shoulder injection therapy was not superior to ESWT therapy. Considering the complications and rebound phenomenon of steroid injections, interventions using ESWT may be a good alternative to treat patients with supraspinatus tendinitis.