[Measurement of bone density in the wrist using X-ray absorptiometry: comparison with measurements of other sites]

Abstract

In order to validate a new technique to measure bone mineral density (BMD) of the forearm with a single X-ray absorptiometry device (DTX 100), we have measured the BMD of 195 women, aged 32 to 83 years, free of metabolic bone disease, simultaneously on two devices: 1. BMD of the ultradistal radius and of the distal radius and ulna on DTX 100, Osteometer, 2. BMD of the lumbar spine, of the proximal femur, of the whole body and of the distal and ultradistal radius by dual X-ray absorptiometry (DXA) on an Hologic 2000 device. The precision of DTX, assessed by 5 repeated measurements on 9 volunteers, was 1% for the distal site and 2% for the ultradistal site. There was a high correlation (r = 0.93) between radial BMD measurement by DTX and Hologic 2000. Correlations between forearm BMDs measured by DTX and whole body BMD were as high (r = 0.80-0.82) as between whole body BMD and lumbar spine (r = 0.82), femoral neck (r = 0.77) and femoral trochanter (r = 0.76). Age-related bone loss measured by DTX was 27% and 31% at the distal and ultra distal radius respectively, as compared to 17% for the lumbar spine, 21% for the femoral neck and 16% for the whole body BMD. In a group of 20 untreated osteoporotic women with vertebral fractures, forearm BMD was as sensitive (T score of -3.1 and -2.9 for distal and ultra distal) as was lumbar spine (T = -2.9) and femoral neck (T = -2.5).(ABSTRACT TRUNCATED AT 250 WORDS)