Longitudinal Changes in Adiposity after a Youth Sport-Related Knee Injury: Informing Post-Traumatic Osteoarthritis Prevention.

Abstract

Youth who experience a sport-related knee injury have elevated odds of overweight or obesity in 3-10 years, compounding their risk for post-traumatic osteoarthritis (PTOA). To inform prevention strategies, this study compared patterns of adiposity change between youth with a sport-related knee injury and uninjured youth in the 2-year period following injury. This was a primary analysis of the Alberta Youth Prevention of Early Osteoarthritis Cohort (PrEOA) prospective cohort study. Fat mass (FM; bioelectrical impedance) of 186 youth (106 injured, 80 uninjured, 62% female, mean age 16±2 years) was assessed at baseline (≤4-months from injury) and 6-, 12-, 18-, and 24-month follow-ups. Linear mixed models examined the association between knee injury and FM change over time after adjusting for confounders. Missing data was addressed with multiple imputation. The injured and uninjured groups did not experience differences in FM gain over the 24-month follow-up (0.1 kg, 95%CI: -0.6, 0.9), and minimal to no between group differences in FM were observed at any time point (6-months: 0.9, 95%CI: -0.2 to 2.0; 12-months: 0.7, 95%CI: -0.4 to 1.9; 18-months: -0.1, 95%CI: -1.4 to 1.1; 24-months -0.9 95%CI: -2.3 to 0.6) or between individuals with ACL tear injuries versus other knee injuries, or female versus male sex. Adiposity gains of youth with a sport-related knee injury over the initial 2-years post-injury may not differ from uninjured youth. Due to similar adiposity gains, the initial post-injury period is a potential window of opportunity to prevent future overweight and obesity, and knee PTOA.