Effect of Steroid Injections in a Knee With Osteoarthritis

This study was a two-year stratified and block-randomized double-blind, placebo controlled clinical trial of the effect of intra-articular triamcinolone 40 mg injectable suspension, administered every 3 months over two years (for a total of 8 doses). The randomization was stratified by the baseline radiographic severity of knee OA (Kellgren and Lawrence grade of 2 or 3) and gender. An interim analysis would have been conducted after the first half of participants has completed the trial. This interim analysis would have allowed the trial to be stopped early for either success or futility, or allow the trial to continue if neither success nor futility has been established. However, the plan for interim analysis was eliminated with the support of the DSMB because of feasibility issues for completing cartilage measurements contemporaneously and because early trial cessation would preclude analysis of informative secondary outcomes. The primary structural outcome objective in this study was cartilage volume loss; secondary structural outcomes included peri-articular bone marrow lesions (BML), tibial peri-articular bone density ratio (paBMD). The primary clinical outcome objective was the pain domain of the WOMAC© LK3.1; secondary clinical outcomes included WOMAC© LK3.1 stiffness and function scores and physical function tests.