William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, USA.
Equine Vet J. 2013 Mar;45(2):176-81. doi: 10.1111/j.2042-3306.2012.00596.x. Epub 2012 Jul 11.
Veterinarians have observed a putative change in the location of humeral stress remodelling in Thoroughbred racehorses with change from dirt to synthetic racetrack surfaces.
To determine whether the location and severity of humeral stress remodelling differs between Thoroughbred racehorses exercising on dirt and synthetic racetrack surfaces, the potential significance of different locations of stress remodelling, and the potential usefulness of scintigraphy for prevention of complete humeral fracture.
Scintigraphic images of humeri from 841 Thoroughbred racehorses at 3 racetracks during 2 years before and after conversion from dirt to synthetic surfaces were evaluated for location and severity of lesions. The effects of surface on lesion distributions were examined using Chi-square or Fisher's exact tests. Archived fractured humeri were examined to determine the location and severity of stress remodelling associated with complete fracture. Databases were queried to determine whether racehorses with scintigraphic lesions suffered humeral fracture and whether racehorses with a complete humeral fracture had had a scintigraphic examination.
Horses at synthetic racetracks had a greater proportion of distal humeral lesions, whereas horses at dirt racetracks had a greater proportion of caudoproximal lesions (P<0.001). Proximal lesions were more likely to be severe than distal lesions (P<0.001). Most complete fractures were associated with caudoproximal lesions, which were more often severe than distal lesions (P = 0.002). None of the horses with a scintigraphic lesion had a complete humeral fracture. None of the horses with a complete humeral fracture underwent scintigraphic examination.
Race surface affected humeral scintigraphic lesion location and hence the location of stress remodelling. Lesion severity was associated with lesion location. Complete humeral fracture was associated with caudoproximal stress remodelling and lack of scintigraphic examination.
Risk for complete humeral fracture may be lower on synthetic surfaces than on dirt surfaces, and, by inference, for horses examined using scintigraphy.
兽医注意到，当从泥地赛道改为合成赛道时，纯种赛马的肱骨应力重塑位置发生了变化。
确定在泥地和合成赛道上运动的纯种赛马的肱骨应力重塑位置和严重程度是否不同，不同位置的应力重塑的潜在意义，以及闪烁扫描术对预防完全肱骨骨折的潜在作用。
在 2 年的时间里，对 3 个赛马场的 841 匹纯种赛马的肱骨闪烁扫描图像进行了评估，以确定病变的位置和严重程度。使用卡方检验或 Fisher 精确检验检查表面对病变分布的影响。对存档的骨折肱骨进行检查，以确定与完全骨折相关的应力重塑的位置和严重程度。查询数据库，以确定有闪烁扫描病变的赛马是否发生肱骨骨折，以及发生完全肱骨骨折的赛马是否进行了闪烁扫描检查。
在合成赛道上的马，其肱骨远端病变的比例较大，而在泥地赛道上的马，其肱骨近侧和尾部病变的比例较大（P<0.001）。近侧病变比远侧病变更严重（P<0.001）。大多数完全骨折与肱骨近侧和尾部病变有关，这些病变比远侧病变更严重（P = 0.002）。没有一匹有闪烁扫描病变的马发生完全肱骨骨折。没有一匹发生完全肱骨骨折的马接受过闪烁扫描检查。
赛马的赛道表面影响肱骨闪烁扫描病变的位置，进而影响应力重塑的位置。病变的严重程度与病变的位置有关。完全肱骨骨折与肱骨近侧和尾部的应力重塑以及缺乏闪烁扫描检查有关。
与在泥地赛道相比，在合成赛道上发生完全肱骨骨折的风险可能较低，通过推理，接受闪烁扫描检查的马也是如此。
