Akbari Shahkhosravi Naeim, C R Bellenzani Maria, M S Davies Helen, Komeili Amin
Department of Veterinary Biosciences, The University of Melbourne, Melbourne, VIC, Australia; Department of Mechanical Engineering, The University of Melbourne, Melbourne, Parkville, VIC 3010, Australia.
School of Veterinary Medicine, Catholic University of Minas Gerais (PUC-MG), Poços de Caldas, MG, Brazil.
J Biomech. 2021 Nov 9;128:110715. doi: 10.1016/j.jbiomech.2021.110715. Epub 2021 Aug 28.
Hoof conformation plays a key role in equine locomotion. Toe-in conformation is an abnormal condition characterized by inward deviation of the limb from its frontal axis. Several studies have documented differences in hoof deformation and hoof kinematics in horses with toe-in and normal hoof conformations. However, the reason behind this has yet to be understood. The present study hypothesizes that a different center of pressure (COP) path underneath the hoof is the cause of different deformation patterns and hoof kinematics in toe-in hooves. In vivo measurements and finite element (FE) analysis were conducted to test the hypothesis. A normal and a toe-in limb were considered for in vivo strain measurements. Strains were measured at three different sites on the hoof wall, and the stride characteristics were investigated using video recording. The magnitude of the minimum principal strain measured at the medial aspect of the toe-in hoof was much lower relative to the normal hoof. Furthermore, the toe-in hoof had a different movement pattern (plaiting) compared to the normal hoof. In the second study, an entire hoof model was simulated from computed tomography (CT) scans of an equine left forelimb. The Neo-Hookean hyperelastic material model was used, and the hoof was under dynamic loading over a complete stride at the trot. Two different COP paths associated with normal and toe-in conformations were assigned to the model. The FE model produced the same in vivo minimum principal strain distributions and successfully showed the different kinematics of the toe-in and normal hooves.
蹄部形态在马的运动中起着关键作用。内翻蹄形态是一种异常情况，其特征是肢体从其额状轴向内偏斜。多项研究记录了内翻蹄和正常蹄形态的马在蹄部变形和蹄部运动学方面的差异。然而，其背后的原因尚不清楚。本研究假设，蹄下不同的压力中心（COP）路径是内翻蹄不同变形模式和蹄部运动学的原因。进行了体内测量和有限元（FE）分析来验证这一假设。在体内应变测量中考虑了一个正常肢体和一个内翻肢体。在蹄壁的三个不同部位测量应变，并使用视频记录研究步幅特征。与正常蹄相比，在内翻蹄内侧测量到的最小主应变的大小要低得多。此外，与正常蹄相比，内翻蹄有不同的运动模式（编织）。在第二项研究中，根据一匹马左前肢的计算机断层扫描（CT）图像模拟了整个蹄模型。使用了新胡克超弹性材料模型，并且蹄在小跑的一个完整步幅上承受动态载荷。将与正常和内翻形态相关的两种不同的COP路径分配给该模型。有限元模型产生了与体内相同的最小主应变分布，并成功地显示了内翻蹄和正常蹄不同的运动学特征。
