Childhood physical performance measures are significantly associated with knee bone area and cartilage volume in adulthood, concluded researchers who presented at the American College of Rheumatology Annual Meeting in Washington, DC. The associations with cartilage volume appear to be mediated by tibial bone area, suggesting that physical activity in childhood can influence adult knee joint health independently, possibly through adaptive mechanisms during growth.
Physical activity in childhood often is recommended as a means to improve adult joint health and function, but there is little evidence to illustrate the correlation between childhood physical performance measures and bone structure in adulthood, the researchers noted. They used real-time data gathered in 1985 on childhood physical performance in a diverse group of 298 persons to determine whether physical activity in youth is associated with more knee cartilage and tibial bone area 25 years later. Knee cartilage and tibial bone area were measured using T1-weighted, fat-suppressed MRI. Adjustments were made for age, sex, body mass index (BMI), and past joint injuries that may affect the cartilage or bone area.
A significant, consistent association was found between greater tibial bone area and childhood physical activity, including physical work capacity, leg and hand muscle strength, and performance of sit-ups and long and short runs. Higher childhood physical work capacity measures were associated with greater tibial cartilage area.
The findings lend support to the effort in many developed countries to encourage children to be more physically active, the researchers noted, but cartilage and bone are still vulnerable to damage that could contribute to osteoarthritis, suggesting a need for injury prevention. They also noted that physical activity helps young patients avoid a high BMI.