[Mineral content of the spongiosa of the lumbar spine determined by computer tomography. Normal values for healthy perimenopausal women and their relation to mechanical stress of the vertebral column].

Healthy perimenopausal women (152) were examined by QCT to quantify the mineral content of the axial skeleton. The density was measured in the spongiosa of the L2-4, using single energy technique and the Cann-Genant calibration phantom. The women, aged 37 to 64, had no history of pathological fractures, ovariectomy, metabolic disease, or hormone therapy. The age-related mean values were 25 mg K2HP04/cm3 lower than the normal values reported by Genant et al. for 203 healthy American women. The 95% confidence interval was distinctly narrower (+/- 40 mg/cm3) than the American confidence interval (+/- 60 mg/cm3). To evaluate the relationship of the BMC to mechanical stress, the BMC was compared with body weight, body mass index (weight/height2), and the lumbar muscle mass estimated from cross sections of the paravertebral muscles in the CT images. The assumption that higher mechanical stress results in higher bone mineralization could not be confirmed.