Drum Martha G, Kawcak Christopher E, Norrdin Robert W, Park Richard D, McIlwraith C Wayne, Les Clifford M
Department of Clinical Sciences, Equine Orthopaedic Research Center, Colorado State University, Fort Collins, CO 80523, USA.
Vet Radiol Ultrasound. 2007 Nov-Dec;48(6):518-27. doi: 10.1111/j.1740-8261.2007.00289.x.
Comparison of subchondral bone density determined by quantitative computed tomography (CT) with gross and histopathologic changes have not been made in horses. The goal of this study was to determine if mean quantitative CT density and mean voxel standard deviation are associated with the presence and severity of osteochondral lesions in the palmar aspect of the distal third metacarpal bone in racing horses. Metacarpophalangeal joints from nine racehorses were imaged using CT and scored for gross damage. Four-millimeter-thick sagittal and 30 degrees palmar dorsal plane sections were cut, decalcified and stained with hematoxylin and eosin from the distal third metacarpal bone. Microscopic osteochondral lesions and subchondral remodeling were scored on a scale of 0-3. Percent subchondral bone, expressed as the ratio of bone volume to tissue volume, was also measured. Mean quantitative CT density and mean voxel standard deviation were measured from three-dimensional models of CT images comparable with histologic sections. Mean quantitative CT density was not associated with lesion severity or number of lesions. A weak correlation between mean quantitative CT density and gross score was found, but mean quantitative CT density was not predictive for gross score. Mean voxel standard deviation was not correlated with gross or histopathologic measures, but was predictive of mild osteochondral lesions. Results support the association of subchondral remodeling with the development of palmar metacarpal lesions. However, there was not a strong correlation between mean quantitative CT density or mean voxel standard deviation and histopathologic lesions of the distal third metacarpal bone.
尚未对马匹进行定量计算机断层扫描（CT）测定的软骨下骨密度与大体及组织病理学变化的比较。本研究的目的是确定平均定量CT密度和平均体素标准差是否与赛马第三掌骨远端掌侧骨软骨损伤的存在及严重程度相关。对9匹赛马的掌指关节进行CT成像，并对大体损伤进行评分。从第三掌骨远端切取4毫米厚的矢状面和30度掌背平面切片，脱钙后用苏木精和伊红染色。对微观骨软骨损伤和软骨下重塑进行0 - 3级评分。还测量了以骨体积与组织体积之比表示的软骨下骨百分比。从与组织学切片相当的CT图像三维模型中测量平均定量CT密度和平均体素标准差。平均定量CT密度与损伤严重程度或损伤数量无关。发现平均定量CT密度与大体评分之间存在弱相关性，但平均定量CT密度不能预测大体评分。平均体素标准差与大体或组织病理学指标无关，但可预测轻度骨软骨损伤。结果支持软骨下重塑与掌侧掌骨损伤发展之间的关联。然而，平均定量CT密度或平均体素标准差与第三掌骨远端的组织病理学损伤之间没有很强的相关性。
