A systematic review of mechanisms of gait speed change post-stroke. Part 1: spatiotemporal parameters and asymmetry ratios.

The review included only studies that already showed a significant change in self-selected walking speed, so it cannot describe interventions that failed to improve speed. Many included studies had high risk of bias because of weak design, lack of control groups, or limited randomization. Sample sizes were small, and each study included 8 to 61 participants. The interventions differed greatly in type, duration, and intensity, so it is hard to compare which ones worked for which mechanism. The studies used different ways to collect spatiotemporal data and different ways to calculate asymmetry ratios. Most studies were in chronic stroke survivors, with few sub-acute or early post-acute studies, so timing after stroke cannot be separated. Self-selected walking speed alone may not reveal underlying impairments in hemiparetic walking. Raw spatiotemporal measures are closely tied to walking speed, so they may not show independent mechanisms of recovery.

Do not treat improved step length, stride length, or cadence as proof that a specific physical therapy intervention restored normal movement. The review included many different interventions, and the authors said these measures may simply follow walking speed rather than identify the mechanism of recovery.