The long-term efficacy and tolerability of hyaluronic acid in adult patients with Kashin–Beck disease of the knee

The aim of this study was to prospectively evaluate the long-term efficacy and tolerability of hyaluronic acid (HA) for the treatment of knee pain due to Kashin–Beck disease (KBD). A total of 113 patients with KBD-based knee pain were treated with a 3-week course of HA. Clinical assessments were performed for each patient at 0 (baseline), 1, 2, 4, 8, 12, 24, and 52 weeks. The primary efficacy measure was the visual analog scale (VAS) pain score. The secondary efficacy measures included the WOMAC A (pain), B (stiffness), and C (function) scores; the total WOMAC score; and the global assessments by patients and physicians. Tolerability was evaluated based on adverse events (AEs) and physician reporting. The VAS was significantly reduced within the first 4 weeks of treatment, and the reduction was maintained over 52 weeks (p < 0.001 at each endpoint). These data were supported by the secondary variables WOMAC A (all p < 0.001), WOMAC B (p = 0.002, 0.003, and 0.019, respectively), WOMAC C (all p < 0.001), total WOMAC (all p < 0.001), and the global assessments by patients and physicians at weeks 12, 24, and 52. No serious AEs were reported, and the overall incidence of AEs was 10.6 %. This study suggests that the intra-articular injection of HA is effective and well tolerated for the treatment of knee pain due to KBD as HA therapy resulted in an improvement of symptoms for at least 52 weeks. Additional randomized double-blind studies are needed to confirm our findings.