Analysis of Factors Affecting Bone Mineral Density in Males with Motor Disability

Abstract

  In previous studies, we have suggested that limitations in long-term physical activity are the cause of the lower bone mineral density (BMD) observed in people with motor disability compared to those without motor disability. The present study aimed to investigate the factors related to fracture risk and thus help reduce the incidence of fractures in people with motor disability. The subjects were 19 males with motor disability. We obtained the following data from all subjects: age; height; weight; body mass index (BMI) ; BMD of the whole body, the whole body excluding the head, the lumbar spine, and total hip; and tissue weight percentage of fat, muscle, and bone. We conducted principal component analysis of each subject's data. The first principal component was interpreted as physique because the factor loadings for weight, body fat percentage, and BMI were high; and the second principal component was interpreted as BMD because the factor loadings for lumbar spine and total hip were high. The results of the present study suggest that height and weight stimuli are involved in BMD even in people with motor disability.