Ability in walking is a predictor of bone mineral density and body composition in prepubertal children with myelomeningocele

This study investigates the relationship in myelomeningocele patients between body composition and bone mineral density in 18 nonambulatory and 23 ambulatory prepubertal children. Fat mass (FM) and fat-free-mass (FFM) were calculated by anthropometry. The bone mineral content (BMC) and density (BMD) were evaluated by dual-energy X-ray absorptiometry. A scattergram of weight and height for age in females and males showed a significant reduction, which was more evident in the nonambulatory group. Percentage body fat was greater than expected, without a difference between groups. The BMD (as the Z-score) was low, but was lower in nonwalking patients. Multivariate analysis indicated that the best predictor for BMD in the nonwalking group was height and forearm circumference. In the walking children, only mid-thigh circumference and weight explained the BMD variation. In conclusion, the ability to walk was a highly significant determinant of bone density, and the development of muscle mass was important in promoting bone and body growth.