How force plate size influences the probability of valid gait data acquisition

Acquiring valid data is one of the major difficulties in gait analysis. Our previous study proved that, using the currently commercially available force plates, there is a low probability that every trial will be successful, and some subjects will have to alter their gait pattern to have a successful trial. In the present study the possibility of using an instrumented floor consisting of more than two force places of small size was investigated. This appears as the most promising solution to simultaneously solve the contrasting requirements of avoiding double contact on each element while acquiring complete gait cycles. In this work the set of mathematical equations previously developed for systems of two force plates was extended to consider any number of plates. Using gait data of 280 subjects from The Ohio State University Gait Laboratory, a software simulation was developed and performed to analyze different combinations of element and system sizes, and to calculate the probability of a successful gait analysis trial.