Verification of simplified gait analysis

In this study we describe a simplified gait analysis system for the estimation of spatial-temporal parameters and kinetic parameters during walking on an instrumented treadmill. This method proposes to compute the values of temporal (length of double support phase, length of stance phase, time of step, time of stride) and few spatial parameters (step length, stride length, cadence) from the graph of time vs. ground reaction force at a constant gait speed. The method was verified by a clinical gait analysis method using a ZEBRIS ultrasound-based measuring system with ARMMODEL software, and the measurement error rate of the method was determined by statistical calculations. The maximum relative value of the average difference of temporal parameters is 0.79% in cycle time and that of spatial parameters is 0.66%. On the basis of statistical analysis, it can be established that the measurement method is reproducible. This system is simple, inexpensive and does not provoke any discomfort to subjects. It can be carried on for long periods of time during a treadmill walk, thus providing new longitudinal information such as the stride-to-stride variability of gait. Several clinical applications can be proposed such as outcome evaluation after different orthopaedical, rheumatological, neurological diseases, and monitoring of the rehabilitation process.