I come from a large African American family. Several of my nephews have been told they have Blount disease. What are the chances my boys will have this problem, too?

Blount disease is an excessive bowing of the lower leg in some children. The condition can occur early on in life (before age three) or later in the teen years. Being overweight seems to be a risk factor for this condition.

Male African-American children seem to be the most likely to develop Blount disease. More than 90 per cent of the children and adolescents with this condition in the U.S. are obese, African-American males. Large-sized parents seem to contribute to the risk for Blount disease. A specific genetic trait hasn't been linked with this problem yet.

Obesity and poor nutrition are two modifiable risk factors. This means you can do something about them. Maintaining a normal weight for height is the first step to possibly preventing Blount disease. Your pediatrician can help track this by calculating your child's BMI or body-mass index.

A good diet with healthy nutrition will help your child maintain his BMI within a normal range for his age. An active lifestyle is also helpful. Working closely with your pediatrician and a nutritionist will give your sons the best means to avoid this condition.