title: Precision of periprosthetic bone mineral density measurements using Hologic Windows versus DOS-based analysis software.
abstract: Dual energy X-ray absorptiometry (DXA) is a precise tool for measuring bone mineral density (BMD) around total joint prostheses. The Hologic "metal-removal hip" analysis package (Hologic Inc., Waltham, MA) is a Microsoft DOS-based analysis platform that has undergone a change in the operating platform to a Microsoft Windows-based system that has also incorporated changes to DXA image manipulation on-screen. We evaluated the impact of these changes on instrument precision by analysis of sequential DXA scans taken on the same day using the Hologic QDR-4500A fan beam densitometer (Hologic Inc.) in 29 subjects after total hip arthroplasty. The coefficient of variation percentage (CV%) for the net pelvic region was 3.04 for Windows versus 2.36 for DOS (p>0.05). The CV% for the net femoral region was 1.75 for Windows versus 1.51 for DOS (p>0.05). Absolute BMD values for the net pelvic and net femoral regions were similar (Bland-Altman, Windows minus DOS; pelvic region mean=-1.0%; femoral region mean=1.3%; p>0.05 for both comparisons). Our results suggest that scans analyzed using each platform may be used interchangeably without the need for a calibration correction.
authors.affiliation: Department of Orthopaedics, Northern General Hospital, Sheffield, United Kingdom.
authors.forename: Nitin R
authors.initials: NR
authors.lastname: Shetty
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Hamer
authors.forename: Ian
authors.initials: I
authors.lastname: Stockley
authors.forename: Richard
authors.initials: R
authors.lastname: Eastell
authors.forename: J Mark
authors.initials: JM
authors.lastname: Wilkinson
mesh_terms: D015502:Absorptiometry, Photon / Q000706:statistics & numerical data*; D000328:Adult; D015519:Bone Density; D005260:Female; D006622:Hip Prosthesis / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012984:Software