Study Summary

Six randomized controlled trials containing a total of 446 patients with knee osteoarthritis were included in this systematic review and meta-analysis comparing intra-articular botulinum toxin A injections vs. control (placebo injection; education only). The pooled outcomes of interest were pain on a Visual Analog Scale (VAS) and the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC), assessed at early and late time intervals (<=4 and >4 weeks). Meta-analysis results demonstrated significantly better improvements in VAS pain scores and WOMAC scores with botulinum toxin A injections vs. control. Meta-regression results suggest the association between botulinum toxin A injections and improved outcomes may be modulated by age and BMI.