Comparing the Efficacy and Safety of Intra-articular Injection Treatments for Hip Osteoarthritis: A Systematic Review and Network Meta-analysis

Background: Hip osteoarthritis is a debilitating condition that leads to progressive joint pain and stiffness. While total hip arthroplasty provides definitive treatment, intra-articular injections offer a less invasive alternative for patients. Several injection options are available, including corticosteroids (CS), hyaluronic acid (HA), and platelet-rich plasma (PRP). Previous reviews and network meta-analyses have compared the short-term efficacy of these injections, but it remains unclear if a particular injection provides superior symptom relief for up to 12 months. Purpose: To provide an updated summary of the current hip intra-articular injection literature and compare the efficacy of all injection types at 3 months, 6 months, and 12 months. Study Design: Systematic review; Level of evidence, 1. Methods: Four databases were queried: Web of Science, Embase, MEDLINE, and Cochrane Central Register of Controlled Trials. The primary outcome measures were the Western Ontario and McMaster Universities Osteoarthritis Index Total Score (WOMAC-Total) and the visual analog scale (VAS) at 3, 6, and 12 months. The Cochrane risk-of-bias tool was used to assess study quality. Treatment effects were expressed as mean differences for the WOMAC-Total and standardized mean differences for the VAS. Results: A total of 14 studies were included in the final analysis with 1254 participants. Eight unique intra-articular injection types were identified: CS, HA of varying molecular weights (low, high, and ultra-high), PRP, CS + high molecular weight HA, PRP + HA, and standard of care/placebo (SOC/PBO) group. When compared with SOC/PBO, no statistically significant differences in WOMAC-Total and VAS outcomes were observed between any injections at 3, 6, or 12 months. Conclusion: There were no statistically significant differences in WOMAC-Total and VAS outcomes at any time point between all injection types to baseline. Future studies should compare the long-term efficacy of various intra-articular injections with a control and examine the efficacy of combined injections. Registration: CRD42024574937 (PROSPERO identifier).