A Sequenced Strategy for Improving Outcomes in People with Knee Osteoarthritis Pain (SKOAP): Study Protocol for an Effectiveness Trial

Guidelines from different organizations for knee osteoarthritis (KOA), one of the leading causes of disability worldwide, are inconsistent in their recommendations for psychological management; pharmacologic treatments, including opioids; and interventional therapies. SKOAP is a Phase III, multisite, randomized, comparative effectiveness clinical trial that includes a pragmatic, 2-phase sequential design to assess the effectiveness of several interventions in participants with KOA. It has three overall objectives: 1. Determine the extent to which conservative treatments, including the effects of duloxetine and its combination with painTrainer (an online, 8-session program teaching pain coping skills), improve pain and function in participants with KOA; 2. Among Phase 1 participants interested in additional treatment following conservative treatment and those inappropriate for Phase 1, determine whether nonsurgical procedural interventions improve pain and function; and 3. Identify clinical and psychosocial phenotypes that predict short- and long-term outcomes. Phase 1 compares (a) Best Practices (e.g. physical therapy, weight loss, NSAIDS, etc.), (b) Best Practices + Duloxetine, and (c) Best Practices + Duloxetine + painTrainer. Phase 2 compares (a) Intra-Articular Injection (Hyaluronic Acid, Steroid + Bupivacaine), (b) Genicular Nerve Block (Liposomal Bupivacaine, Sham RFA + Steroid Injection), and (c) Genicular Nerve Radiofrequency Ablation (+ Steroid Injection). In addition to comparing treatments, SKOAP will identify clinical and patient-level factors associated with treatment response. These results will inform evidence-based guidelines by offering well-tested, effective, non-opioid alternatives and lead to improved patient selection for treatment. Funded by National Institutes of Arthritis and Musculoskeletal and Skin Diseases (UH3 AR077360).