Intra-articular, single-shot co-injection of hyaluronic acid and corticosteroids in knee osteoarthritis: A randomized controlled trial

The aim of the present study was to investigate whether the co-injection of hyaluronic acid (HA) and corticosteroids (CS) was superior to HA alone in the treatment of knee OA. A total of 120 participants with symptomatic knee OA were recruited and formed the intention-to-treat population for a 6-month follow-up. In the HA group, patients received a single-shot injection of 4 ml HA. In the HA&CS group, patients received a co-injection of 3 ml compound betamethasone solution and 4 ml HA. Visual analog scale (VAS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and knee flexion motion were assessed as primary outcomes. Patients in the HA&CS group exhibited better pain relief and knee function at the time points of week 1, month 1 and month 3 (P<0.05). For the last follow-up at month 6, the values did not differ significantly between these two groups. Patients in both groups exhibited improvement in pain, knee function, and range of motion following injection. For the final follow-up at month 6, the mean VAS score, WOMAC score and knee flexion motion were still superior to that prior to treatment, but the values did not differ significantly. The co-injection of HA and CS provided a rapid improvement in pain relief, knee function, and range of motion, but did not differ significantly from that of HA alone in the long term effect.