Falling is a major cause of injury for individuals with neuromuscular deficits, with research needed to help detect and mitigate falls for these populations. For individuals with lower-limb amputations, fall detection devices can be conveniently integrated with their prosthesis to detect and reduce the consequences of falls. To improve the accuracy of existing devices, our first study investigated the detection accuracy of different fall types with a wearable device placed on an individual’s shank or lower-limb prosthesis and explored ways to improve that accuracy. Fall detection accuracy differed across fall types, and the addition of a Spectral Residual algorithm, typically used to improve anomaly detection in time series data, did not improve accuracy. Therefore, when developing fall detection devices, consideration of the fall type is needed.

Our next study investigated how step width affects balance control and response strategies during perturbed walking, as many clinical populations walk with wider steps. During steady state walking, wider steps were associated with decreased balance control but not with a change in plantarflexion moment. Further, increasing step widths were associated with increased gluteus medius activity and reduced hip abduction and ankle inversion moment, which suggests healthy subjects rely more on a lateral ankle strategy to maintain balance at increasing step widths. During perturbed walking, lateral, but not medial, surface translations adversely affected balance control. Further, wider steps did not change the balance response strategy following the mediolateral surface translation perturbations, which suggests healthy individuals have the capacity to respond similarly to the perturbation at different step widths.

Finally, our modeling study investigated the influence of step width on muscle contributions to response strategies following the lateral perturbation. The plantarflexors switched their contributions from a lateral to medial ground reaction force at wider steps, which reduced frontal-plane external moment demands on some distal muscles. In addition, the gluteus medius muscle fibers were shorter than their optimal length at wider steps, which affected its ability to meet increased balance demands. Finally, the plantarflexors and gluteus medius were increasingly critical for foot placement at wider steps and therefore should be rehabilitation targets.