A computer simulation study on the causal relationship between walking and physical malfunctions in older adults

Abstract

The purpose of the present study was to investigate the causal relationship between walking pattern and physical malfunction using a computer simulation method with a biomechanical walking model. In this computer simulation, the musculoskeletal system was represented by a three-dimensional 14-rigid-link model and 60 muscle models. Muscular forces were controlled by a neuronal system model consisting of 16 pairs of neural oscillators. In the computational experiment, five types of walking models were constructed: an intact model, a delayed response model, a weak muscle model, an inclined posture model, and a joint contracture model. These malfunction factors were hypothesized to have a causal relationship with walking characteristics in older adults. The simulation revealed that the delayed response in the neuronal system was primarily related to walking stability. In addition, the weakening of muscles was strongly related to the reduction of the walking step length. The inclined posture and joint contracture also influenced the walking pattern, but not significantly. The use of such a computer simulation method is essential in order to clarify the causal relationship between body function and walking pattern in older adults.