Brief ReportsKnee Extensor and Flexor Torque Variability During Maximal Strength Testing and Change in Knee Pain and Physical Function at 60-Mo Follow-Up The Multicenter Osteoarthritis Study (MOST)Schroeder, Allison MD; Wang, Na MA; Felson, David T. MD; Lewis, Cora E. MD, MSPH; Nevitt, Michael C. PhD, MPH; Segal, Neil A. MDAuthor Information From the Department of PM&R, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (AS); Biostatistics and Epidemiology Data Analytics Center (BEDAC), Boston University School of Public Health, Boston, Massachusetts (NW); Boston University, Boston, Massachusetts (DTF); University of Alabama at Birmingham, Birmingham, Alabama (CEL); University of California, San Francisco, San Francisco, California (MCN); University of Kansas Medical Center, Kansas City, Kansas (NAS); and The University of Iowa, Iowa City, Iowa (NAS). All correspondence should be addressed to: Allison Schroeder, MD, 600 Hennepin Ave, Suite 310, Minneapolis, MN 55403. Presented at the AAP Annual Meeting in 2019 in Puerto Rico. The Multicenter Osteoarthritis Study was funded by the National Institutes of Health (U01-AG18820, U01-AG18832, U01-AG18947, and U01-AG19069). Allison Schroeder is in training. Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.ajpmr.com). American Journal of Physical Medicine & Rehabilitation: February 2021 - Volume 100 - Issue 2 - p 196-201 doi: 10.1097/PHM.0000000000001587 Buy SDC Metrics Abstract As the population ages, there is a growing burden owing to musculoskeletal diseases, such as knee osteoarthritis, and subsequent functional decline. In the absence of a cure, there is a need to identify factors amenable to intervention to prevent or slow this process. The Multicenter Osteoarthritis Study cohort was developed for this purpose. In this study, associations between variability in peak knee flexor and extensor torque at baseline and worsening of pain and physical function over the subsequent 60 mos were assessed in a cohort of 2680 participants. The highest quartile of baseline knee flexor torque variability was found to be associated longitudinally with worsening pain (fourth quartile ß estimate, mean ± SE, 0.49 ± 0.19; P = 0.0115; with R2 = 0.28 and P for trend across quartiles = 0.0370) and physical function scores (fourth quartile ß estimate, mean ± SE, 1.39 ± 0.64; P = 0.0296; with R2 = 0.25 and P for trend across quartiles = 0.0371), after adjusting for baseline knee osteoarthritis and maximum knee flexor torque. There were no associations between baseline knee extensor torque and worsening pain or physical function by 60 mos. The presence of greater variability in maximum knee flexor strength may identify patients who may benefit from therapies aimed at preventing worsening knee pain and physical function. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.