Factors that may mediate the relationship between physical activity and the risk for developing knee osteoarthritis

Abstract

Studies investigating the effect of physical activity on risk for developing osteoarthritis at weight-bearing joints have reported conflicting results. We examine evidence to suggest that this may be due to the existence of subgroups of individuals who differ in their response to physical activity, as well as methodological issues associated with the assessment of knee joint structure and physical activity. Recommendations for future studies of physical activity and the development of knee osteoarthritis are discussed. IntroductionIt is widely accepted that participation in physical activity is associated with physical, psychological and social benefits [1]. Physical activity not only reduces the risk for cardiovascular disease [2] (a major cause of mortality in developed countries) but is also recommended for the management of obesity and the treatment of mental illness [3]. Globally, a vast number of large-scale public health campaigns is aimed at promoting physical activity. Exercise is also widely recommended by health care professionals in the prevention and management of chronic health conditions such as osteoarthritis (OA). However, our knowledge of the effect of physical activity on risk for developing OA is limited.OA is the most common joint disorder affecting the elderly. In particular, radiographic knee OA affects at least 30% of people aged over 60 years [4] and is a major cause of functional disability [5]. With our population ageing, the prevalence of OA in the developed world is expected to increase and it is anticipated that OA will become the fourth leading cause of disability in the coming decades [6]. A population-wide initiative, such as promotion of physical activity, has the potential to contribute inadvertently to the growing burden of this disease.Epidemiological studies that have investigated the effect of physical activity on the knee joint have reported conflicting findings. Although some studies have reported that physical activity is associated with risk for knee OA [7][8][9], other studies have shown that physical activity may have no effect [10,11] or may even protect the knee joint from degenerative changes [12,13]. These conflicting findings may be a result of individual variation in response to exercise and/or different methodology employed by studies to measure knee structure and physical activity.We propose that there may be subgroups of individuals who differ in their response to physical activity within our community. Although some individuals may have specific characteristics that enable them to exercise without increasing their risk for knee OA, others may require these individual factors and/or their exercise programme to be modified before they can commence or continue to exercise safely. In this review, we examine the roles played by a number of parameters that may mediate the relationship between physical activity and knee OA. We focus on the role of physical activity in the risk for developing OA, and do not consider its effect on those individuals with estab...

Until it hurts? Epidemiology of musculoskeletal pain in youth sports

“…4). These results were contrary to our hypothesis that the combined effect of excess body weight and sports activity might be more harmful to the lower limb joints (because of a higher physical load) than to the joints of the upper limb 24,26) . In a previous study, overweight was considered to be a risk factor for repeated forearm fractures 27) .…”

“…To identify a high risk population, we also assessed whether excess sports activity was particularly associated with musculoskeletal pain among students with high body mass index (BMI). Overweight adolescents may experience greater impacts of physical activity on musculoskeletal pain than lean adolescents [24][25][26] . In our study, the interaction between BMI and sports activity was not significantly associated with the overall pain prevalence (P = 0.95); however, this interaction was significant for upper limb pain (P = 0.048), but not for pain at other locations (P > 0.5).…”

Patellar Cartilage: T2 Values and Morphologic Abnormalities at 3.0-T MR Imaging in Relation to Physical Activity in Asymptomatic Subjects from the Osteoarthritis Initiative

“…Knowledge of the relationship of physical activity and the evolution of OA is limited, as researchers ( 39,(41)(42)(43) investigating the effect of physical activity on weight-bearing joints have reported confl icting results. Investigators in a number of studies (12)(13)(14)(15)(16) examined OA risk factors in relation to quantitative and qualitative cartilage loss determined with MR imaging.…”

“…Multiple risk factors have been linked to OA in epidemiologic studies (38)(39)(40), including age, female sex, obesity, sports activities, previous injury, proprioceptive defi cits, and genetic elements. Knowledge of the relationship of physical activity and the evolution of OA is limited, as researchers ( 39,(41)(42)(43) investigating the effect of physical activity on weight-bearing joints have reported confl icting results.…”

Protective Effect of Sinomenine on Cartilage Degradation and Chondrocytes Apoptosis

“…With worldwide population ageing, the incidence of OA is rapidly increasing, and it is anticipated that OA will become the fourth leading cause of disability in the coming decades. 1) OA is characterized by progressive degradation of articular cartilage and chondrocytes apoptosis and death. 2) Chondrocytes apoptosis has been identiˆed as a vital reason for cell loss and is now considered as an important factor contributing to degradation of extracellular matrix (ECM) in OA cartilage.…”