Bone mineral density in children with myelomeningocele.

The aim of the present study was to document bone mineral density (BMD) in children with myelomeningocele and to identify variables that contribute to reduced BMD. The study included 24 children with myelomeningocele (nine males, 15 females; age range 4-18y), who had varied levels of neurological impairment (thoracic/high-lumbar, n=6; mid-lumbar, n=9; sacral, n=9) and ambulatory status (non-ambulators, n=12; part-time ambulators n=2; full-time ambulators, n=10). BMD measurements of the femoral neck and whole body using dual energy X-ray absorptiometry assessments of dietary calcium intake, and serum markers of bone metabolism were obtained. BMD is presented as standardized scores (z-scores) which are age- and sex-matched to normally developing children. The mean femoral-neck z-score was -2.41. Femoral-neck z-scores differed significantly according to ambulatory status, with lower z-scores in children who were wheelchair-dependent (p=0.03). The mean z-score at the femoral neck demonstrated a trend toward lower z-scores in children with higher levels of lesions. Almost all children met their recommended daily intake of calcium. Markers of bone metabolism were normal in all patients. This study demonstrates that reduced BMD is a major complication in children with myelomeningocele. There is a significant relationship with low BMD in children who are wheelchair-dependent, a trend in those with higher neurological levels, and no relationship between fractures and reduced BMD.