Bone Mineral Density of the Hip Measured with Dual-energy X-ray Absorptiometry in Normal Elderly Women and in Patients with Hip Fracture

Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DEXA) in 133 normal females on five regions of the femoral site: neck, trochanteric, intertrochanteric, Ward's triangle, and total area of the proximal femur. One hundred and twenty-five women (56 older than 65, range 65-97, and 69 with an age range of 21-65) were also examined for spinal bone mineral density. The mean in vivo precision (CV%) of the measurements with repositioning assessed on five young and eight elderly patients was ranged from 0.7% to 1.7% but lower for Ward's triangle (CV = 2.95% and 3.87%). Between 30 and 90 years, a linear age-related bone mineral decrease was found at all sites with a similar magnitude of bone loss for the femoral neck, total or intertrochanteric regions (-33% to -39%). A greater decrease was found for the Ward's triangle region (-61%). In the subgroup of elderly women (65-97 years old), the lumbar BMD measured with an anteroposterior incidence did not decrease significantly with age, contrasting with an average 27% decrease of the BMD of the hip between 65 and 90 years of age. In addition, 31 patients suffering either from a cervical (n = 12) or pertrochanteric (n = 19) fracture were measured on their contralateral femur 15 to 30 days after the fracture event. The mean calculated BMD values were, depending on the measured area, from 14% to 21% lower than those reported for age-matched controls (z-score from -1.11 to -0.65). A fracture threshold was determined for each site from this population and the elderly controls.(ABSTRACT TRUNCATED AT 250 WORDS)