O2172 EFFECT OF FRACTURE AND IMMOBILIZATION IN BONE MINERAL DENSITY AND BONE MECHANICAL PARAMETERS IN POSTMENOPAUSAL WOMEN WITH DISTAL RADIUS FRACTURE. PRELIMINARY REPORT OF AN ONGOING PROSPECTIVE ANALYSIS

Abstract

Aims: To determine the effect of fracture and immobilization on bone mineral density and mechanical parameters in postemenopausal women with a distal radius fracture. Methods: Seventeen postmenopausal women with a distal radius fracture with an indication for conservative treatment were included in the study. pQCT measurements of the fractured forearm were performed 2–3 days after the fracture, at 10 days after the fracture and at cast removal (35–45 days). All measurements were performed at a 10mm, 20mm and 40mm distance from a reference line set at the most proximal part of the distal radioulnar joint. Cortical, trabecular and total density and SSIx, SSIy and SSIpolar parameters were assessed. Results: At the fractured forearm, a high statistically signiþcant decrease of cortical density was observed only between second measurement and cast removal at 10 and 20mm (p< 0.01) Total density was not signiþcantly altered and trabecular density at 10mm was signiþcantly increased at cast removal compared to values at the time of the fracture (p< 0.01). Subcortical bone density at 10mm was also signiþcantly decreased at cast removal (p< 0.01). At cast removal, SSIx and SSI-polar parameters of the fractured forearm were also statistically signiþcantly decreased at distances of 10 and 20mm (p< 0.05). Conclusions: Distal radius fractures in postmenopausal women treated conservatively lead to a decrease of cortical density and an increase of trabecular density near the fracture site. They also aggravate bending and torsional mechanical properties. The shift from cortical bone to trabecular bone seems to be time-dependent and is signiþcant at cast removal.