OBJECTIVE: The aim of our study was to evaluate the diagnostic agreement of quantitative sonography of the radius and proximal phalanx and dual-energy X-ray absorptiometry (DXA) of the radius, lumbar spine, and femoral neck for the detection of osteoporosis. MATERIALS AND METHODS: In 95 women (mean age, 53 +/- 13 years) and 26 men (mean age, 53 +/- 13 years), DXA measurements of the lumbar spine (posterior-anterior, L1-L4) and the femoral neck, as well as quantitative sonography of the radius and proximal phalanx of the third finger were obtained. The percentage of patients below a given threshold was calculated for each imaging technique. A T score of less than -2.5 indicated presence of osteoporosis. Diagnostic agreement in identifying individuals with osteoporosis was assessed using kappa scores. RESULTS: Between 14% and 22% of the patients were classified as osteoporotic after DXA of the various regions of interest of the radius, 31% after DXA of the spine, 43% after DXA of the femoral neck, 32% after quantitative sonography of the distal radius, and 34% after quantitative sonography of the phalanx of the third finger. Correlation coefficients between T values for quantitative sonography and those for DXA varied between not significant and 0.54 at the different regions. Kappa analysis showed the diagnostic agreement among quantitative sonography and DXA to be fair to moderate (kappa = 0.38-0.48). The highest agreement was between quantitative sonography of the proximal phalanx of the third finger and DXA of the total radius (kappa 0.48; p < 0.05). CONCLUSION: Considerable diagnostic disagreement exists between quantitative sonography and DXA of the forearm, as is true for most quantitative techniques in the assessment of skeletal status. The lack of correlation makes quantitative sonography impractical for routine diagnostic use but might characterize different parameters related to bone quality.
OBJECTIVE: The aim of our study was to evaluate the diagnostic agreement of quantitative sonography of the radius and proximal phalanx and dual-energy X-ray absorptiometry (DXA) of the radius, lumbar spine, and femoral neck for the detection of osteoporosis. MATERIALS AND METHODS: In 95 women (mean age, 53 +/- 13 years) and 26 men (mean age, 53 +/- 13 years), DXA measurements of the lumbar spine (posterior-anterior, L1-L4) and the femoral neck, as well as quantitative sonography of the radius and proximal phalanx of the third finger were obtained. The percentage of patients below a given threshold was calculated for each imaging technique. A T score of less than -2.5 indicated presence of osteoporosis. Diagnostic agreement in identifying individuals with osteoporosis was assessed using kappa scores. RESULTS: Between 14% and 22% of the patients were classified as osteoporotic after DXA of the various regions of interest of the radius, 31% after DXA of the spine, 43% after DXA of the femoral neck, 32% after quantitative sonography of the distal radius, and 34% after quantitative sonography of the phalanx of the third finger. Correlation coefficients between T values for quantitative sonography and those for DXA varied between not significant and 0.54 at the different regions. Kappa analysis showed the diagnostic agreement among quantitative sonography and DXA to be fair to moderate (kappa = 0.38-0.48). The highest agreement was between quantitative sonography of the proximal phalanx of the third finger and DXA of the total radius (kappa 0.48; p < 0.05). CONCLUSION: Considerable diagnostic disagreement exists between quantitative sonography and DXA of the forearm, as is true for most quantitative techniques in the assessment of skeletal status. The lack of correlation makes quantitative sonography impractical for routine diagnostic use but might characterize different parameters related to bone quality.