Compared to limb pain of other origin, ultrasonographic osteodensitometry reveals loss of bone density in complex regional pain syndrome.

Local osteopenia and altered bone metabolism are major complications of complex regional pain syndrome (CRPS), but quantitative assessment is difficult unless using X-ray or dual-energy X-ray absorptiometry. Ultrasound-based measurement of bone density (UBD) is a possible alternative but has never been used to detect unilateral disease such as CRPS. Therefore, the main outcome measure of this prospective study was the diagnostic utility of UBD in patients with lower-limb CRPS.