A comparative study of the efficacy of ultrasonics and extracorporeal shock wave in the treatment of tennis elbow: a meta-analysis of randomized controlled trials

BACKGROUND: Tennis elbow or lateral epicondylitis is a common source of pain among craftsmen. Although it cannot be completely resolved, extracorporeal shock wave therapy (ESWT) and ultrasonics (US) have been found to be effective for tennis elbow as highlighted in previously published randomized controlled trials (RCTs) and reviews. However, the efficacy of these two therapies in treating tennis elbow is unknown. This meta-analysis compares the effectiveness of ESWT and US in relieving pain and restoring the functions of tennis elbow following tendinopathy. METHODS: RCTs published in the PubMed, Embase, Cochrane Library, and SpringerLink databases comparing ESWT and US in treating tennis elbow were identified by a software and manual search. The risk of bias and clinical relevance of the included studies were assessed. Publication bias was explored using funnel plot and statistical tests (Egger’s test and Begg’s test). The major outcomes of the studies were analyzed using the Review Manager 5.3. RESULTS: Five RCTs comprising five patients were included in the present meta-analysis. The results revealed a significantly lower VAS score of pain in the ESWT group (1 month: MD = 4.47, p = 0.0001; 3 months: MD = 20.32, p < 0.00001; and 6 months: MD = 4.32, p < 0.0001) compared to US. Besides, the grip strength was markedly higher 3 months after the intervention in ESWT (MD = 8.87, p < 0.00001) than in the US group. Although no significant difference was observed in the scores of the elbow function after 3 months of treatment (SMD = 1.51, p = 0.13), the subjective scores of elbow functions were found to be better in the ESWT group (SMD = 3.34; p = 0.0008) compared to the US group. CONCLUSIONS: Although there was no significant difference in the elbow function evaluation scores between ESWT and US, the superiority of the ESWT group in the VAS of pain (both at 1 month, 3 months, and 6 months follow-ups) raised grip strength in ESWT group and the scores for subjective evaluation of efficacy indicated that ESWT offers more effective therapy for lateral epicondylitis than US therapy. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13018-019-1290-y) contains supplementary material, which is available to authorized users.