Batka Richard J, Brown Todd J, Mcmillan Kathryn P, Meadows Rena M, Jones Kathryn J, Haulcomb Melissa M
Department of Anatomy & Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS 5025 C, Indianapolis, Indiana; R & D Services Richard L. Roudebush VA Medical Center, 1481 W. 10th Street, Mail Code 151, Rm C-3074, Indianapolis, Indiana.
Anat Rec (Hoboken). 2014 Oct;297(10):1839-64. doi: 10.1002/ar.22955. Epub 2014 Jun 3.
Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript, we accomplish three things: (1) review the interaction between speed and locomotion variables in rodent studies, (2) comprehensively analyze the relationship between speed and 162 locomotion variables in a group of 16 wild-type mice using the CatWalk gait analysis system, and (3) develop and test a statistical method in which locomotion variables are analyzed and reported in the context of speed. Notable results include the following: (1) over 90% of variables, reported by CatWalk, were dependent on speed with an average R(2) value of 0.624, (2) most variables were related to speed in a nonlinear manner, (3) current methods of controlling for speed are insufficient, and (4) the linear mixed model is an appropriate and effective statistical method for locomotion analyses that is inclusive of speed-dependent relationships. Given the pervasive dependency of locomotion variables on speed, we maintain that valid conclusions from locomotion analyses cannot be made unless they are analyzed and reported within the context of speed.
运动分析如今在许多动物物种中广泛应用，以了解疾病中的运动缺陷、神经损伤后的功能恢复以及各种治疗方法的有效性。最近，啮齿动物运动分析在各种研究中已成为越来越受欢迎的方法。速度是运动中一个不可分割的方面，但仍未被完全理解，并且在分析数据时其影响常常没有得到恰当考虑。在这篇综合性稿件中，我们完成了三件事：（1）回顾啮齿动物研究中速度与运动变量之间的相互作用，（2）使用CatWalk步态分析系统全面分析一组16只野生型小鼠中速度与162个运动变量之间的关系，（3）开发并测试一种统计方法，在速度背景下分析和报告运动变量。显著结果如下：（1）CatWalk报告的超过90%的变量依赖于速度，平均R²值为0.624，（2）大多数变量与速度呈非线性关系，（3）当前控制速度的方法不足，（4）线性混合模型是用于包含速度相关关系的运动分析的一种合适且有效的统计方法。鉴于运动变量对速度的普遍依赖性，我们认为，除非在速度背景下进行分析和报告，否则无法从运动分析中得出有效的结论。
