Efficacy of intra-articular hyaluronic acid injections in hip osteoarthritis: a meta-analysis of randomized controlled trials

There is less credible evidence of using of intra-articular injections of hyaluronic acid (HA) to treat hip osteoarthritis (OA). This study is to determine the therapeutic effects and risk of adverse events of HA administration for hip OA. The MEDLINE, Cochrane of Systematic Reviews, Cochrane Clinical Trial Register and EMBASE, were searched for articles published. Eligible studies were limited to trials of HA with a randomized design. A total of six studies were included in this the meta-analysis. The pooled effect size of improved pain scores from pretreatment was -0.72 (95%CI; -1.06 to -0.39; P < 0.05). The standardized mean difference (SMD) of improved Lequesne's index and McMaster Universities Osteoarthritis Index (WOMAC) was -0.74 (95%CI, -1.42 to -0.51; P < 0.05) and -7.75 (95%CI, -14.28 to -1.21; P < 0.05), respectively. The pooled effect size of improved pain scores compared HA with different controls was 0.03 (95%CI; -0.20 to 0.26; P < 0.05). The SMD of improved Lequesne's index and WOMAC was -0.24 (95%CI, -0.50 to 0.02; P > 0.05) and -0.13 (95%CI, 0.64 to 0.37; P > 0.05). There were no significant differences between HA and control group in adverse events (RR: 0.94; 95%CI, 0.41 to 2.20; P > 0.05). Intra-articular HA in hip OA can significantly reduce pain and improve functional recovery when compared with the condition before treatment. However, there seems no significant difference between HA and saline or other treatments. Currently, available evidence indicated that intra-articular HA in hip OA would not be increased risk of adverse events.