Abstract
Determinants that affect bone density in disabled children and adolescents with neuromuscular
disorders have not been differentially investigated well. We performed dual-energy
X-ray absorptiometry of the lumbar spine in three groups (Duchenne muscular dystrophy,
n = 16; other neuromuscular diseases, n = 11; and cerebral palsy, n = 18) providing height-age- and sex-adjusted z scores. Mobility was assessed by functional tests. Seven Duchenne patients were taking
glucocorticoids; two reported previous treatment. We documented vitamin D blood levels
and markers of bone turnover. Many patients presented low bone density for height-age
(mean z score = − 0.86 ± 1.47). Areal bone density increased with age in the cerebral palsy
and “other neuromuscular disease” groups, however, the Duchenne group demonstrated
a decrease of z scores (r = − 0.622, p = 0.010). Tanner stage, body mass index, and mobility were independent variables
affecting bone density. Vitamin D levels were low, but similar to those reported in
healthy children. We conclude that bone mineral density in disabled children is mainly
determined by their level of physical maturity, thriving, and mobility.
Keywords
Duchenne muscular dystrophy - cerebral palsy - bone mineral density - ambulatory ability
