Chronic joint pain in the lower body is associated with gait differences independent from radiographic osteoarthritis

Gait is an important indicator of health. Chronic lower body pain may impair gait and lead to morbidity and mortality. We investigated the associations between lower body pain and gait in community-dwelling individuals, independent from osteoarthritis (OA). This population based cohort study included 2304 Rotterdam Study participants who underwent electronic walkway gait assessment. Thirty different variables resulting from gait assessment were summarized into seven gait domains using principle components analysis: i.e. Rhythm, Variability, Phases, Pace, Tandem, Turning, and Base of Support. Chronic lower body pain was assessed using pain drawings. OA was defined as a Kellgren & Lawrence score of 2 or higher on radiographs of the hip and/or knee. Linear regression analysis was used to study associations. Participants with chronic pain in the leg and hip, had lower Rhythm, Phases, and Pace, independent from OA. Additionally, we found unilateral pain to associate with larger gait asymmetry. No associations were found between chronic pain and the other gait domains, including gait variability. However, within individuals with hip pain, gait variability was higher in individuals with radiographic OA compared to those without OA. This is the first population based study showing chronic lower body pain associates with gait differences independent from OA. Participants with pain were found to walk with slower and smaller steps, longer double support and more asymmetry. Proper care and treatment of chronic pain could be a way of reducing gait problems and thereby fall risk and associated mortality. In addition, gait assessment may help identifying individuals with OA from those having pain due to other causes.