Development of Diseased Joints Model for Analysis of Abnormal Walking and Evaluation Methods of Impact at Landing on the Ground

本研究致力于开发可用于研究包括异常行走在内的各种行走条件的模拟模型。对于负责整形外科和康复的人以及自主机车系统的设计者来说，这是一个具有挑战性的课题。在本研究中的模拟模型中，每条腿上的一个关节对应于一个患病的患者：模型中的关节不能产生一个力矩来完全控制连接的身体的运动，但可以向它们传递一个力。在相同的行走条件下，模拟的正常和异常行走的特征差异被评估和讨论，作为对其余健全关节的补偿作用。当模型的病变关节位于较高位置时，作用变得更大。研究了动作的还原方法，以类似于正常行走的方式行走，并在健全的关节处采用允许的补偿动作。行走速度变慢，步长变短，步幅变宽，动作就会减少：这些行走模式分别可以在疼痛、肌肉无力和肌肉发育不全的病人、老人和婴儿的行走中看到。仿真模型还验证了拐杖和短腿支架作为助行器的作用，结果与患者在使用助行器时的实际情况吻合较好，行走或慢跑过程中强烈或重复的冲击力可能会损伤关节或导致关节退行性变，即关节病变。通过平面模型分析了飞机着陆时的减震机理。该模型和包括身体测试在内的实验结果表明，弯曲的膝盖、脚踝关节和鞋子中的软垫有效地缓冲了撞击。

This research deals with the development of simulation models which can be used to investigate various walking conditions including abnormal walking. It is a challenging subject for those who are in charge of orthopedics and rehabilitation as well as designers of autonomous locomotive systems. The simulation model in this study has a joint in either leg corresponding to a diseased one of patients : the joint of the model cannot generate a moment fully to control the motion of the connected bodies but can transmit a force to them.Differences in characteristics between normal and abnormal walking simulated under the same walking conditions are evaluated and discussed as compensatory actions at the remaining sound joints. The actions became greater when the diseased joint of the model was located in a higher position. Reduction methods of the action were examined to walk in a pattern resembling with a normal walking with admissible compensatorv actions at the sound joints. The action was reduced by a slower walking velocity, a shorter step length, and a wider step width : these walking patterns could be seen in the walking of patients, old men, and infants who have pains, weak muscles, and undeveloped muscles, respectively. The functions of a cane and a short-leg brace as walking aids were also examined by the simulation model, and results showed a good agreement with the real situation of patients' walk using the aid.Strong or repetitive impact forces in walking or jogging may damage joints or lead to degenerative ones, that is, diseased joints. The mechanism of absorbing the impact at landing on the ground was examined by a planar model. The model and experimental results including cadaver tests showed that a flexed knee, an ankle joint, and a soft insert in shoes cushioned the impact effectively.