Efficacy of single intra-articular 2% sodium hyaluronate versus corticosteroid injection in isolated patellofemoral osteoarthritis: A double-blind, randomized controlled trial

Abstract

Introduction/objective: Patellofemoral osteoarthritis (PFOA) is unicompartmental arthritis with a hallmark of anterior knee pain, disturbing quality of life. Unlike tibiofemoral osteoarthritis, there is still a lack of evidence regarding intra-articular injection for isolated PFOA patients. This study aims to evaluate the efficacy of intra-articular hyaluronic acid (HA) in comparison to corticosteroid (CS) injections for pain reduction and improvement in knee function in isolated PFOA patients. Methods: This was a prospective, double-blind, randomized controlled trial. Patients with isolated PFOA based on clinical and radiographic features were randomized 1:1 to receive a single-shot, 2 ​ml intra-articular 2% sodium hyaluronate plus 0.5% mannitol or a 2 ​ml solution comprising 1 ​ml of 40 ​mg triamcinolone acetonide and 1% lidocaine. The visual analog scale (VAS) for anterior knee pain, Kujala score, pain during injection, and adverse events were assessed during a 6-month follow-up. Results: A total of 60 patients were included. Both groups demonstrated statistically significant improvements in VAS pain and Kujala scores from 48 ​h post-injection to 6 months compared to baseline (p ​< ​0.05). At the 6-month follow-up, there were no significant between-group differences in VAS pain (mean difference [95% CI]: −4.46 [-11.2, 2.28]; p ​= ​0.270) or Kujala scores (2.56 [-4.08, 9.2]; p ​= ​0.45). However, at 48 ​h, 72 ​h, and 1 week post-injection, the CS group reported statistically significantly greater pain relief compared to the HA group (mean differences: 10.33, 9.67, and 7.67; p ​= ​0.002, 0.003, and 0.013, respectively). No significant differences were observed in pain during injection or adverse events. Conclusion: Intra-articular HA and CS injections provide comparable pain reduction and functional score improvement at 6-month follow-up in patients with PFOA, with better pain relief in the first week for the CS group. Intra-articular HA may be an alternative to CS, with equivalent results but without increasing the risk of chondrotoxicity and cartilage volume loss, especially in isolated PFOA patients whose tibiofemoral compartment cartilage is relatively preserved. Clinical Trial Registration: TCTR20200709009. Level of Evidence: Level I.