title: Third metacarpal bone mineral density assessment in the standing horse by dual X-ray absorptiometry: suitability, precision and accuracy.
abstract: Bone mineral density (BMD) is correlated to mechanical properties of bone. In the horse, dual energy X-ray absorptiometry (DXA) has yet only been performed ex-vivo, but a new portable DXA device would be ideal for in-vivo BMD measurement. We explored field suitability, precision and accuracy of this device for in-vivo third metacarpal density assessment. Precision was analysed by calculating measurement variation under repeated measurement tests with (reproducibility) and without (repeatability) limb repositioning. Repeatability and reproducibility were tested ex-vivo, at the same time that intra- and inter-operator reproducibility were assessed in-vivo. In order to test accuracy, bone mineral content (BMC) of several bone samples determined by DXA and ashing were compared. Repeatability was 1.47% and reproducibility 1.69% ex-vivo. In-vivo reproducibility varied between 2.91 and 4.06% for intra-operator test and between 3.13 and 5.53% for inter-operator test. BMC measured by DXA and ash weight were highly correlated (R2>0.99). In conclusion, under described conditions this DXA device is usable, accurate and precise. Its sensitiveness reaches 8.23% in an individual longitudinal monitoring. Using the third metacarpal bone as an example, we have shown that this device is suitable for experimental or clinical monitoring.
authors.affiliation: Department of Human Nutrition and Food Safety, INRA, St Genes-Champanelle, France. michael.donabedian@clermont.inra.fr
authors.forename: M
authors.initials: M
authors.lastname: Donabedian
authors.forename: C
authors.initials: C
authors.lastname: Delguste
authors.forename: G
authors.initials: G
authors.lastname: Perona
authors.forename: P
authors.initials: P
authors.lastname: Lebecque
authors.forename: F
authors.initials: F
authors.lastname: Duboeuf
authors.forename: O
authors.initials: O
authors.lastname: Lepaga
authors.forename: W
authors.initials: W
authors.lastname: Martin-Rosset
mesh_terms: D015502:Absorptiometry, Photon / Q000662:veterinary*; D000818:Animals; D015519:Bone Density; D006736:Horses; D008663:Metacarpus / Q000000981:diagnostic imaging*; D011187:Posture; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity