Yorke Elizabeth H, Judy Carter E, Saveraid Travis C, McGowan Conor P, Caldwell Fred J
Department of Clinical Sciences, Auburn University College of Veterinary Medicine, 1500 Wire Road, Auburn, AL, 36849.
Vet Radiol Ultrasound. 2014 Jan-Feb;55(1):35-44. doi: 10.1111/vru.12082. Epub 2013 Jul 26.
Distal border fragments of the navicular bone are increasingly being detected due to the improved capabilities of magnetic resonance imaging (MRI), but their clinical significance remains unclear. The purpose of this retrospective study was to describe the location, size, and frequency of fragments in a cohort of horses presented for MRI of the foot and to compare MRI findings with severity of lameness. Archived MRI studies and medical records were searched from March 2006 to June 2008. Horses were included if a distal border fragment of the navicular bone was visible in MRI scans. Confidence interval comparisons and linear regression analyses were used to test hypotheses that fragments were associated with lameness and lameness severity was positively correlated with fragment volume and biaxial location. A total of 453 horses (874 limbs) were included. Fragments were identified in 60 horses (13.25%) and 90 limbs (10.3%). Fifty percent of the horses had unilateral fragments and 50% had bilateral fragments. Fragments were located at the lateral (62.2%), medial (8.89%), or medial and lateral (28.9%) angles of the distal border of the navicular bone. There was no increased probability of being categorized as lame if a fragment was present. There was no significant difference in fragment volume across lameness severity categorizations. Confidence intervals indicated a slightly increased probability of being classified as lame if both medial and lateral fragments were present. Findings indicated that distal border fragments of the navicular bone in equine MRI studies are unlikely to be related to existing lameness.
由于磁共振成像（MRI）技术的改进，舟骨远端边缘碎片越来越多地被检测到，但其临床意义仍不明确。这项回顾性研究的目的是描述一组因足部MRI检查而就诊的马匹中碎片的位置、大小和频率，并将MRI检查结果与跛行严重程度进行比较。检索了2006年3月至2008年6月期间的存档MRI研究和病历。如果在MRI扫描中可见舟骨远端边缘碎片，则纳入该马匹。使用置信区间比较和线性回归分析来检验以下假设：碎片与跛行有关，且跛行严重程度与碎片体积和双轴位置呈正相关。总共纳入了453匹马（874条肢体）。在60匹马（13.25%）和90条肢体（10.3%）中发现了碎片。50%的马匹有单侧碎片，50%有双侧碎片。碎片位于舟骨远端边缘的外侧（62.2%）、内侧（8.89%）或内侧和外侧（28.9%）角。如果存在碎片，被归类为跛行的可能性没有增加。在不同跛行严重程度分类中，碎片体积没有显著差异。置信区间表明，如果同时存在内侧和外侧碎片，被归类为跛行的可能性略有增加。研究结果表明，在马的MRI研究中，舟骨远端边缘碎片不太可能与现有的跛行有关。
