Bone density and size in ambulatory children with cerebral palsy

Abstract

Children with cerebral palsy (CP) have deficient bone growth and, consequently, an increased propensity for non-traumatic fractures.1 However, most studies of bone in children with CP have been limited to individuals with moderate to severe involvement (Gross Motor Function Classification System [GMFCS] level III–V). These children have low bone mass in both the lumbar spine2–4 and the lower extremities,5,6 with the level of deficiency being related to ambulatory ability and severity of involvement.4,7 The deficiencies in bone are associated with a high rate of fragility fractures.2,8 Thus bone acquisition and fractures are clearly a problem for children with moderate to severe CP. Much less is known about the bone health of higher-functioning children with CP. These children may also be at risk for deficient bone acquisition due to muscle weakness and mobility limitations. In recent years, bone acquisition has become an issue even for children and adolescents without disability owing to the increased awareness that insufficient bone accrual during childhood is likely a precursor to the early onset of osteoporosis later in life.9 As care improves and the lifespan of persons with CP increases, identifying antecedents to adult diseases will become increasingly important. The aim of this study was to examine axial and appendicular bone properties in ambulatory children with CP to determine the relation between bone properties and functional level. We hypothesized that even highly functional children with CP would have diminished bone size and density, and that the deficits would increase at higher GMFCS levels.