Lin Cheng-Chung, Wang Shi-Nuan, Lu Ming, Chao Tzu-Yi, Lu Tung-Wu, Wu Ching-Ho
Department of Electrical Engineering, Fu Jen Catholic University, New Taipei City, Taiwan.
Institute of Veterinary Clinical Science, National Taiwan University, Taipei, Taiwan.
PeerJ. 2020 Jun 26;8:e9379. doi: 10.7717/peerj.9379. eCollection 2020.
Soft tissue artifacts (STAs) are a source of error in marker-based gait analysis in dogs. While some studies have revealed the existence of STAs in the canine hindlimb, STAs and their influence on kinematic gait analysis remain unclear.
Thirteen healthy Taiwan dogs affixed with twenty skin markers on the thigh and crus were recruited. Soft tissue artifacts and their influence on the determination of segment poses and stifle angles were assessed by simultaneously measuring marker trajectories and kinematics of the underlying bones via a model-based fluoroscopic analysis method.
Markers on the thigh showed higher STAs than those on the crus, with root-mean-square amplitudes up to 15.5 mm. None of the tested marker clusters were able to accurately reproduce the skeletal poses, in which the maximum root-mean-square deviations ranged from 3.4° to 8.1°. The use of markers resulted in overestimated stifle flexion during 40-60% of the gait cycle and underestimated stifle flexion during 80-90% of the gait cycle.
Considerable magnitudes and effects of STAs on the marker-based 3D gait analysis of dogs were demonstrated. The results indicate that the development of error-compensation techniques based on knowledge regarding STAs is warranted for more accurate gait analysis.
软组织伪影（STAs）是犬类基于标记的步态分析中误差的一个来源。虽然一些研究已经揭示了犬后肢中存在软组织伪影，但软组织伪影及其对运动学步态分析的影响仍不清楚。
招募了13只健康的台湾犬，在其大腿和小腿上粘贴了20个皮肤标记。通过基于模型的荧光透视分析方法同时测量标记轨迹和下层骨骼的运动学，评估软组织伪影及其对节段姿态和 stifle 角测定的影响。
大腿上的标记显示出比小腿上的标记更高的软组织伪影，均方根振幅高达15.5毫米。没有一个测试的标记簇能够准确再现骨骼姿态，其中最大均方根偏差范围为3.4°至8.1°。使用标记导致在40 - 60%的步态周期中 stifle 屈曲被高估，在80 - 90%的步态周期中 stifle 屈曲被低估。
证明了软组织伪影对犬类基于标记的三维步态分析具有相当大的幅度和影响。结果表明，基于关于软组织伪影的知识开发误差补偿技术对于更准确的步态分析是必要的。
