Fractures and joint and muscle pain all increase in the face of overweight

A recent study concludes that children and adolescents who are overweight are more likely than normal-weight counterparts to suffer bone fractures and have joint and muscle pain. The study, sponsored by The National Institutes of Health, also found that overweight youth were more likely than non-overweight youth to develop changes in the knee joint that make movement more difficult.

Participants included 355 African American and Caucasian children and adolescents from Washington, D.C. Of these, 227 were classified as overweight. Participants were classified as "overweight" if they had a body mass index (BMI) above the 95th percentile for height and weight or as "non-overweight" if they had a BMI above the 5th percentile but no higher than the 95th percentile for height and weight.

At entry, the children underwent physical examination and were queried about joint-, bone-, or muscle-related problems. Participants also responded to a questionnaire that gauged the impact that their weight has had on quality of life by ranking, on a five-point scale, how statements about impaired mobility applied to them. The researchers used dual energy x-ray absorptiometry (DXA) to detect effects of overweight on feet, ankles, and knees.

Results suggest that overweight youth are more likely than non-overweight children to have fractures and muscle and joint pain.

The most common self-reported joint complaint was knee pain (21.4% of overweight youth, 16.7% of non-overweight youth). Overweight youth were also more likely than non-overweight youth to report impaired mobility. DXA scanning showed that overweight youth were more likely than non-overweight youth to exhibit changes in thigh- and leg-bone union at the knee.

Lead researcher Jack A. Yanovski, MD, PhD, head of the Unit on Growth and Obesity at NIH's National Institute of Child Health and Human Development, and his coworkers noted that, although overweight children and adults have a greater bone density than their non-overweight counterparts, the increase in density did not protect youth in the study from fractures.

The study was published in the June 2006 issue of Pediatrics.