Gait speed and symmetry in individuals with unilateral trans-tibial amputation

The purpose of this study was to determine the influence of walking speed on gait symmetry in individuals with unilateral traumatic trans-tibial amputation (TTA) while walking with their prostheses. Fifteen individuals (11 males, 4 females; average age 41.0 ± 10 years) with TTA participated. Each participant was required to walk at six speeds: self-selected walking speed (SSWS), two speeds slower, and three speeds faster than SSWS. Walking speeds were randomized and controlled by a custom made light (tracking) system programmed by the researcher. Subjects walked on a level surface with the GAITRite™ electronic walkway incorporated into the walking pathway.; Mean step length and mean step time of both lower extremities were determined at each walking speed for each participant. Step length symmetry (SLS) and step time symmetry (STS) were calculated by dividing the mean value obtained for the amputated leg by the mean value obtained for the intact leg. A ratio of 1.00 was considered symmetrical. Two repeated measures analysis of variance followed by Post-hoc Tukey analyses were performed to determine differences in STS and SLS in relation to walking speed and to identify pair wise differences. The speed at which both STS and SLS occurred for each participant was then determined and a paired t-test was used to compare the difference in the two speeds. The alpha level was set at .05.; The findings of this study indicate that individuals with TTA choose a SSWS that is slower than the healthy population. Additionally, the speed at which step length and step time becomes most symmetrical is close to the SSWS of healthy individuals of the same age group. And step length and step time became less symmetrical as walking speed varied from the most symmetrical walking speed.; The findings from this study indicate that individuals with TTA should be encouraged to walk at a speed that is closer to SSWS of healthy, age-matched individuals to produce the most symmetrical gait pattern. Walking at a speed that is closer to SSWS of healthy age-matched individuals may trigger central pattern generator gait control and minimize energy expenditure.