Son Jung K, De Paz Patroys, Kim Jihyun, Sanaei Reza, Ryu Seungho, Bailey Simon, Davies Helen M S
Department of Veterinary Biosciences, The University of Melbourne, Melbourne, Australia.
Department of Science, Technology, Engineering and Mathematics, University of South Australia, Adelaide, Australia.
Equine Vet J. 2025 Nov;57(6):1600-1611. doi: 10.1111/evj.14484. Epub 2025 Feb 19.
Changes in the third metacarpal (MC3) mid-diaphyseal dimensions were measured radiographically in young Thoroughbred racehorses through race training and found to be associated with a higher risk of shin soreness. However, it is still unclear whether such negative MC3 morphologies are set congenitally or through development.
To quantify MC3 bone dimensional changes through growth.
Longitudinal.
Twenty privately owned Thoroughbred foals were radiographed bimonthly from birth to 14 months of age. Four linear MC3 parameters (proximodistal MC3 length, mid-diaphyseal dorsal and palmar cortical bone thickness, and dorsopalmar medullary width) were measured using ImageJ on lateromedial radiographs. Associations with age (growth), MC3 length, differences between left and right limbs, and between sexes were analysed separately using a linear mixed effects model.
The dorsal cortical bone thickness showed a positive linear relationship with growth (0.4 0.02 mm per month, p < 0.001, 95% CI [0.37, 0.44]) while the medullary width did not change. The relative thickness of the dorsal cortical bone thickness compared with the medullary cavity width and palmar cortical bone thickness also increased through growth (0.2 0.01 mm per month, p < 0.001, 95% CI [0.14, 0.19]). The dorsal cortical bone thickness was positively associated with MC3 length (0.07 0.0001 mm per mm increase in MC3 length, p < 0.001, 95% CI [0.05, 0.08]) and the relative thickness of the dorsal cortical bone thickness (RI) to the rest of the diaphyseal parameters (0.02 0.01 per mm increase in MC3 length, p = 0.01, 95% CI [0.01, 0.03]).
A limited number of foals were included with similar breeding.
The mid-diaphyseal dorsal cortical bone thickness and proportions could be measured to monitor musculoskeletal development and identify foals at increased risk of shin soreness or those that are immature or otherwise need more time before the commencement of fast training.
通过对年轻纯种赛马进行赛马训练期间的X线摄影测量第三掌骨（MC3）骨干中部尺寸变化，发现其与胫痛风险较高相关。然而，目前仍不清楚这种MC3的负面形态是先天性的还是发育过程中形成的。
量化MC3骨骼在生长过程中的尺寸变化。
纵向研究。
对20匹私有纯种马驹从出生到14月龄每两个月进行一次X线摄影。使用ImageJ软件在内外侧X线片上测量4个MC3线性参数（近远侧MC3长度、骨干中部背侧和掌侧皮质骨厚度以及背掌侧髓腔宽度）。分别使用线性混合效应模型分析与年龄（生长）、MC3长度、左右肢差异以及性别之间的关联。
背侧皮质骨厚度与生长呈正线性关系（每月增加0.4±0.02mm，p<0.001，95%可信区间[0.37,0.44]），而髓腔宽度没有变化。背侧皮质骨厚度相对于髓腔宽度和掌侧皮质骨厚度的相对厚度也随着生长而增加（每月增加0.2±0.01mm，p<0.001，95%可信区间[0.14,0.19]）。背侧皮质骨厚度与MC3长度呈正相关（MC3长度每增加1mm增加0.07±0.0001mm，p<0.001，95%可信区间[0.05,0.08]），背侧皮质骨厚度（RI）与骨干其余参数的相对厚度与MC3长度每增加1mm增加0.02±0.01（p=0.01，95%可信区间[0.01,0.03]）。
纳入的马驹数量有限且育种相似。
可以测量骨干中部背侧皮质骨厚度和比例，以监测肌肉骨骼发育，并识别胫痛风险增加的马驹，或那些未成熟或在开始快速训练前需要更多时间的马驹。
