Safety of Intra-Articular Hyaluronic Acid for Knee Osteoarthritis: Systematic Review and Meta-Analysis of Randomized Trials Involving More than 8,000 Patients

The objective of this systematic review and meta-analysis was to report the safety of intra-articular hyaluronic acid (IAHA) in patients with symptomatic knee osteoarthritis (OA).We identified randomized controlled trials reporting the safety of IAHA versus IA saline in adults with symptomatic knee OA. Main safety outcomes were adverse events (AEs), local AEs, serious adverse events (SAEs), study withdrawals, and AE-related study withdrawals.A total of 35 randomized controlled trials with 38 group comparisons comprising 8,078 unique patients (IAHA: 4,295, IA saline: 3,783) were included in the meta-analysis. Comparing IAHA with IA saline over a median of 6 months follow-up, there were no differences in the risk of AEs (42.4% vs. 39.7%, risk ratio [RR] = 1.01, 95% CI = 0.96-1.07, P = 0.61), SAEs (1.8% vs. 1.2%, RR = 1.44, 95% CI = 0.91-2.26, P=0.12), study withdrawals (12.3% vs. 12.7%, RR = 0.99, 95% CI = 0.87-1.12, P = 0.83), or AE-related study withdrawals (2.7% vs. 2.1%, RR = 1.37, 95% CI = 0.97-1.93, P = 0.08). Local AEs, all of which were nonserious, were more common with IAHA vs. IA saline (14.5% vs. 11.7%, RR = 1.21, 95% CI = 1.07-1.36, P = 0.003) and typically resolved within days.IAHA was shown to be safe for use in patients with symptomatic knee OA. Compared with IA saline, IAHA is associated with an increased risk of nonserious, transient local reactions. There was no evidence to suggest any additional safety risks of IAHA.