Foot side detection from lower lumbar spine acceleration

•New algorithm to discriminate between the sides of foot contact using lumbar accelerometer.•The algorithm was validated against instrumented treadmill.•Foot contact side can be reliably obtained from the mediolateral acceleration of the lumbar spine.

The purpose of this paper is to present a reliable algorithm to discriminate between left/right foot contact using an accelerometer located over the lower lumbar spine. With the given accelerometer frame orientation, the side detection algorithm, based on the sign of the derivative of the sinusoidal shape obtained from the filtered mediolateral (ML) acceleration, showed 100% correct side detection for all subjects at all walking velocities. From the obtained results, it is concluded that in healthy subjects, the side of subsequent foot contact can be reliably obtained from the ML acceleration pattern of the lower lumbar spine.