Obesity is a risk factor for patellar tendinopathy in middle-aged adults without clinical knee osteoarthritis — ASN Events

Obesity is a risk factor for patellar tendinopathy in middle-aged adults without clinical knee osteoarthritis (#215)

Jesssica Fairley 1 , Jason Toppi 1 , Flavia M Cicuttini 1 , Anita E Wluka 1 , Graham G Giles 1 2 3 , Jill Cook 4 , Richard O'Sullivan 5 , Yuanyuan Wang 1
  1. School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
  2. Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, School of Population Health, The University of Melbourne, Carlton, Victoria, Australia
  3. Cancer Epidemiology Centre, The Cancer Council Victoria, Carlton, Victoria , Australia
  4. Department of Physiotherapy, School of Primary Health Care, Faculty of Medicine, Nursing and Health Sciences, Monash University, Frankston, Victoria, Australia
  5. Department of Medicine, Monash University Medical School, Epworth Hospital, Melbourne, Victoria , Australia

Objectives: Patellar tendinopathy is a common cause of activity-related anterior knee pain. Data is conflicting as to whether obesity is a risk factor. The aim of this study was to determine the relationship between obesity and patellar tendinopathy in asymptomatic middle-aged adults.

Methods: 296 participants aged 50-79 years with no significant knee pain or injury were recruited from an existing cohort. Measures of obesity included measured body mass index (BMI), self-reported weight at age 18-21 years and heaviest weight. Fat-free mass and fat mass were measured using bioelectrical impedance. Participants underwent magnetic resonance imaging of the dominant knee. Patellar tendinopathy was defined as hyperintense regions of characteristic pattern, size and distribution on at least 2 consecutive slices on both T1- and T2-weighted images.

Results: The prevalence of patellar tendinopathy was 50.3%. Current weight (OR 1.03, 95% CI 1.01-1.05), BMI (OR 1.09, 95% CI 1.03-1.15), weight at age of 18-21 years (OR 1.06, 95% CI 1.03-1.10) and heaviest weight (OR 1.04, 95% CI 1.02-1.06) were all positively associated with the prevalence of patellar tendinopathy. Neither fat mass nor fat-free mass were associated with patellar tendinopathy when they were included in the same regression model.

Conclusion: Patellar tendinopathy is common in asymptomatic older individuals and associated with both a current and past history of obesity assessed by BMI or body weight, but not body fat mass. The findings suggest a mechanical pathogenesis of patellar tendinopathy and highlight the importance of avoiding weight gain from early adulthood in reducing the risk of patellar tendinopathy.