[Optimal cut-off value of phalangeal radiographic absorptiometry to identify osteoporosis in postmenopausal women].

Objective To study the optimal cut-off value of phalangeal radiographic absorptiometry(RA)to identify osteoporosis in postmenopausal women.Methods A total of 650postmenopausal women were recruited in this study.Bone mineral density(BMD)at lumbar spine and left proximal femur neck was measured by dual-energy X-ray absorptiometry(DXA)as the standard method to identify postmenopausal osteoprosis.Phalangeal bone density was estimated by the use of RA.Optimal cut-off value of phalangeal RA was determined using a ROC curve for screening the ostreoporosis cases.Results When the cut-off value of phalangeal RA was T score≤-2.5,the sensitivity was 74.2%,the specificity was 72.9%.When the cut-off value was T score≤-2.21,the sensitivity was 81.4%,the specificity was 62.0%.Conclusion The cut-off value of phalangeal RA as T score≤-2.21.which has higher sensitivity could be optimal to identify postmenopausal osteoporosis.