Complexity of center of pressure using approximate entropy in fallers and non-fallers during walking

The goal of this study was to understand the mechanism of falls in the elderly using the complexity analysis of center of pressure (CoP) in those who fall and those who do not fall. Approximate Entropy (ApEn) was calculated to determine the levels of complexity of CoP during walking on an instrumented treadmill. The findings reveal that those who fall showed smaller ApEn in the medial-lateral direction of CoP (CoPx) compared with non-fallers. This smaller ApEn, which is an indication of a decreased complexity in fallers, may also induce decreased adaptive responses to the changes in environment during movement. Further studies would be warranted if the level of ApEn in CoPx can be used to predict the risk of falls and the criteria when using exercise programs to improve the function of joint mobility related to decreasing the occurrence of falls in the elderly.