Botulinum toxin injection versus steroid injection in tennis elbow: a systematic review and meta-analysis

Abstract

INTRODUCTION: Tennis elbow has a prevalence of 1-3% of population. A previous systematic review published in 2018 found that steroid injection may be more effective than botulinum toxin injection (BTX) patients with tennis elbow. However, the analysis included different injection sites of BTX. This systematic review aimed to compare the outcomes of BTX versus steroid injection in patients with tennis elbow by using the same injection site. EVIDENCE ACQUISITION: The inclusion criteria were randomized controlled trials that compared BTX versus steroid injection at the same injection site in adult patients with tennis elbow. There were four databases used for searching including PubMed, Cochrane library, Scopus, and CINAHL. The last search was performed on April 18, 2023. The outcomes of the study were Visual Analog Scale (VAS) and grip strength at 4, 8, and 12 weeks after the treatment. These outcomes were compared between the BTX and steroid injection. EVIDENCE SYNTHESIS: There were 161 articles from four databases search. Of those, 85 articles remaining after removing duplicated articles. In total, two studies compared BTX versus steroid injection in patients with tennis elbow. For VAS, there was only significantly different of pain reduction between the BTX and steroid injection at week 4 after treatment. The steroid injection group had significantly higher VAS reduction than the BTX group by 25.75 (95% confidence interval of 8.51, 42.99). For grip strength, there were significantly different grip strengths between both groups at week 4 and 8 after treatment. The BTX group had significantly lower grip strengths than the steroid injection group by -7.11 and -4.77 at week 4 and 8 after treatment. CONCLUSIONS: Steroid injection may be more beneficial than botulinum injection in patients with tennis elbow who received the injection at the epicondyle.