To have or not to have (knee arthroplasty) two years after a simple home-based exercise program in patients with severe knee osteoarthritis eligible for knee arthroplasty: A 2-year exploratory follow-up of the QUADX-1 randomized trial

Background and purposeIn the QUADX-1 trial, we randomized 140 patients with severe knee osteoarthritis (OA) eligible for a knee arthroplasty to home-based exercise for 12 weeks. Seventy-nine (68%) of the 117 patients, who completed the exercise intervention, postponed surgery. Here, we report how many patients, who completed the 12-week exercise intervention, had received a knee arthroplasty at 2 years and describe their initial exercise response. MethodsFrom the QUADX-1 trial, we had the following: isometric knee-extensor strength, Oxford Knee Score (OKS), Knee Osteoarthritis Outcome Score (KOOS), average knee pain last week (0-10 numeric rating scale [NRS]), 6-minute walk test, stair climbing test, and self-reported exercise behaviour. ResultsAt the 2-year follow-up, 50 (43%) of the 117 patients had received a knee arthroplasty (KA group) and 67 (57%) had not (NO-KA group). Compared with the KA group, the NO-KA group had less severe radiographic OA at baseline (KL grade 4: 38% vs 55%) and showed greater-- and often clinically relevant--improvements after the 12-week exercise intervention, including knee pain (-2.1 vs -0.1 NRS points), OKS (+6.9 vs +0.5 points), and KOOS ADL (+13.9 vs +1.3 points). ConclusionTwo years after completing the initial 12-week QUADX-1 exercise intervention, more than half the cohort had not received a knee arthroplasty despite initially being considered eligible. Those who had not received a knee arthroplasty at two years had less severe radiographic OA at baseline and generally responded better to 12-week exercise two years earlier, compared to those who had. ClinicalTrials.gov-IDNCT02931058.