Bone Health of Subjects with Down Syndrome: Is there a Link with the Stabilometric Characteristics Measured as a Surrogate for Body Tonicity?

AbstractOsteoporosis represents one of the main factors contributing to premature morbidity in individuals with Down Syndrome (DS) who are characterized by muscle hypotonia. The purpose of this study was to assess bone ultrasound properties in a cohort of subjects with DS with reference to age and body tonicity. A number of 193 subjects with DS and 246 healthy subjects participated in this study. Broadband Ultrasound Attenuation (BUA) was measured. Stabilometric performances were obtained from a force platform. Subjects were divided into four age groups (mean age 10.8 yrs, 15.2 yrs, 20.5 yrs, 33.4 yrs respectively) using a decision tree procedure. Subjects with DS differed from controls for BUA in the two older age groups. Stabilometric performances of the controls were higher for each age group, showing an improvement of stability and tonicity with age. Results of this study showed the bone degradation that occurs at the end of adolescence and in adulthood in individuals with DS. BUA values and stabilometric performances were able to distinguish DS from controls in the two older age groups whose low bone status may be explained by a deficient postural tone