Estimating bone change in patients with severe disability

To evaluate bone change in severely disabled patients, bone density was assessed on X-ray pictures by the microdensitometry (MD) method, and urinary hydroxyproline (U-HYP), urinary glycosaminoglycans (U-GAG) serum calcium (S-Ca) and serum alkaline phosphatase (S-AP) were assessed in 43 patients (mean age 16 years) at the National Sanatrium Ehime Hospital. On division of the severity of bone change into grades 0 to 3 using the MD method. U-HYP was found to be significantly higher in grades 2 and 3 than in controls. Tendencies were similar for U-GAG and S-AP. U-HYP in immobile patients was significantly higher than in mobile patients. Immobilisation was one of the most important contributors to the development of bone change and results obtained using the MD method, U-HYP and U-GAG were valuable-indices of the bone change in severely disabled patients.