Variability of Gait is Dependent on Direction of Progression: Implications for Active Control

Typical healthy walking displays greater variability in the mediolateral direction compared to the anteroposterior direction. This greater variability is thought to represent increased uncertainty in movement. As a result, it has been postulated that the mediolateral direction of gait requires more active control by the central nervous system while the anteroposterior direction is controlled through passive actions. However, this theory has only been tested on gait where progression occurs in the anteroposterior direction. Therefore, the purpose of this study was to investigate how the amount of variability is affected if progression occurs in the mediolateral direction using a lateral stepping gait. Results showed the anteroposterior direction had a significantly greater amount of variability than the mediolateral direction (p\u3c0.001). The results do not support current models of a partition of active control to different anatomical planes. Rather, it seems that other physical entities involved in motion, such as momentum and inertia, are able to decrease the dependence on active control from the central nervous system. In a lateral stepping gait, such physical entities were no longer assisting in the anteroposterior direction but had a larger impact in the mediolateral direction as it was the direction of progression. As a result variability in the anteroposterior direction increased. Thus, it is possible to infer increased reliance on active control from the central nervous system in the direction orthogonal to progression

An unstable shoe with a rocker bottom redistributes external work

The purpose of this study was to examine the external work performed by individuals wearing a rocker bottom shoe compared to a standard shoe. It was hypothesized that individuals wearing a rocker bottom shoe would have changes in the amount of work over the course of contact with the ground. External work on the body’s centre of mass (BCOM) was calculated for individuals in both conditions. Comparisons for external work were done for positive and negative work for the entire stance phase as well as the initial double support, single support and terminal double support periods. The results revealed that while wearing the rocker bottom shoes, individuals performed an increased amount of negative work and decreased positive work in the initial double support followed by increased positive work in single support compared to a standard sole shoe. Individuals also performed a decreased amount of positive and negative work in terminal double support when wearing the rocker bottom shoes. There were no differences, however, when the stance phase was considered undivided to subphases for either positive or negative work. The results indicate that use of rocker bottom shoes redistributes external work to earlier in the gait cycle, which may not be as energetically efficient. This shift will probably result in increased metabolic energy expenditure as it will require more energy output from proximal hip musculature, which is not as mechanically efficient as the ankle joint in late stance. This could be desirable for individuals who are wearing the shoes for increased caloric burn such as an exercise setting. Furthermore, the increased external work in single support may be causing additional work from the hip extensor musculature (i.e. gluteus maximus). This could possibly be desirable for strengthening and conditioning of the hip extensors

Spatiotemporal Changes Posttreatment in Peripheral Arterial Disease

Accumulating evidence suggests revascularization of peripheral arterial disease (PAD) limbs results in limited improvement in functional gait parameters, suggesting underlying locomotor system pathology. Spatial and temporal (ST) gait parameters are well studied in patients with PAD at baseline and are abnormal when compared to controls. The purpose of this study was to systematically review and critically analyze the available data on ST gait parameters before and after interventions. A full review of literature was conducted and articles were included which examined ST gait parameters before and after intervention (revascularization and exercise). Thirty-three intervention articles were identified based on 154 articles that evaluated ST gait parameters in PAD. Four articles fully assessed ST gait parameters before and after intervention and were included in our analysis. The systematic review of the literature revealed a limited number of studies assessing ST gait parameters. Of those found, results demonstrated the absence of improvement in gait parameters due to either exercise or surgical intervention.Our study demonstrates significant lack of research examining the effectiveness of treatments on ST gait parameters in patients with PAD. Based on the four published articles, ST gait parameters failed to significantly improve in patients with PAD following intervention

Spatiotemporal Changes Posttreatment in Peripheral Arterial Disease

Accumulating evidence suggests revascularization of peripheral arterial disease (PAD) limbs results in limited improvement in functional gait parameters, suggesting underlying locomotor system pathology. Spatial and temporal (ST) gait parameters are well studied in patients with PAD at baseline and are abnormal when compared to controls. The purpose of this study was to systematically review and critically analyze the available data on ST gait parameters before and after interventions. A full review of literature was conducted and articles were included which examined ST gait parameters before and after intervention (revascularization and exercise). Thirty-three intervention articles were identified based on 154 articles that evaluated ST gait parameters in PAD. Four articles fully assessed ST gait parameters before and after intervention and were included in our analysis. The systematic review of the literature revealed a limited number of studies assessing ST gait parameters. Of those found, results demonstrated the absence of improvement in gait parameters due to either exercise or surgical intervention. Our study demonstrates significant lack of research examining the effectiveness of treatments on ST gait parameters in patients with PAD. Based on the four published articles, ST gait parameters failed to significantly improve in patients with PAD following intervention