Impact of adding distal forearm DXA to hip and spine measurements on DXA report

Abstract

Dual energy X-ray absorptiometry (DXA) is the gold standard modality for non-invasive diagnosis of osteoporosis but controversy exists about the optimal site (s) for bone mineral density (BMD) measurement. The objective was to find out impact of adding distal forearm BMD to hip and spine measurements on final diagnosis of a DXA study. This prospective study recruited 279 consecutive patients [female 256 (92%); male 23 (8%)] with a mean age of 63.25 ± 10.62 years from April 2011 to April 2012. The BMD was measured over hip (total hip and femoral neck), spine and distal forearm in all patients. Based on T-Score values of hip and spine (2 sites), diagnosis was normal in 34%, low bone mass in 40% and osteoporosis in 26% patients. However, adding distal forearm BMD and T-score (3 sites), diagnosis was normal in 28%, low bone mass in 37% and osteoporosis in 35%. Therefore, distal forearm BMD has upstaged the diagnosis from normal to low bone mass in 14%, from normal to osteoporosis in 2% and from low bone mass to osteoporosis in 18% patients. We conclude that combining distal forearm BMD with spine and hip can identify more patients with low bone mass or osteoporosis.