Measurement of Equine Bone Mineral Content by Radiographic Absorptiometry Using CR and Ortho Systems

Abstract

The purpose of this investigation was to establish the accuracy and precision of bone mineral content (BMC) measurements made by the total radiographic bone aluminum equivalence (RBAE) method in the evaluation of the horse skeleton. To study the accuracies and precisions of the total RBAE method, the analogue ortho system and the digital computed radiography (CR) system were used. For investigation of the correlation with the bone ash weight and total RBAE value, the clinically healthy left third metacarpal bone (McIII) of 30 post-mortem horses were used. In the evaluation of the accuracies and precisions of total RBAE method, three different values were measured using an aluminum stepwedge. A high positive correlation was noted between the bone ash weight of the measured region and the total RBAE value. The precisions of the total RBAE method were high when measurements with a low total RBAE value by the ortho system and a high total RBAE value by the CR system were excluded, use of the development-fixing solution was limited to within 3 days in the ortho system. The RBAE value changed when the X-ray irradiation angle was altered in the horizontal and vertical directions in both systems, thus an accurate dorsopalmar view is demanded. Based on these findings, the total RBAE method of McIII in horses using the ortho and CR systems had high precision, suggesting it is a reliable tool for the measurement of BMC in horses.