Three Dimensional Analysis of Aquatic Treadmill Walking In Individuals With Stroke

Abstract

People with stroke can gain benefits from gait training in water, mostly due to buoyancy. Water resistance and drag force effect can make conventional aquatic walking more challenging in the early phase of gait rehabilitation. PURPOSE: To examine the biomechanical characteristics of aquatic treadmill walking (ATW) as compared to conventional aquatic walking (CAW) in individuals with stroke. METHODS: A repeated measures study was used to compare two groups (Stroke and Non-Stroke) and two walking modes (ATW & CAW). A total of 20 individuals with stroke and 20 healthy adults were recruited and tested for their walking in chest-depth water at a matched comfortable speed on both aquatic treadmill (Aqua Gaiter, FERNO, Ohio, 2002) and movable pool floor (KBE Bauelemate, GmbH & Co., Germany, 2002). All participants had to perform three testing trials for each walking condition with a 2-minute break in between. All testing trials were captured by six underwater lenses (Underwater Camera Company of America, San Diego, CA, 2005) connected to six digital video cameras (Canon, Japan, 2006). Spatiotemporal and kinematic gait variables were processed using the Vicon Motus software v.9.0 (Vicon, Oxford, UK, 2006). A total of 16 reflective markers were placed on the bony landmarks of the lower extremities. RESULTS: Significant differences were found in spatiotemporal and kinematic gait variables in both groups. During ATW, the stroke group showed significantly shorter stride length and stride time in both affected and non-affected limbs while they demonstrated greater cadence and stance/swing time ratio (Ps<0.05). The stroke group showed significantly greater peak angles in the hip extension, knee extension and ankle dorsi-flexion on the non-affected limb during ATW (Ps<0.05). Decreased peak angles in the hip abduction and hip external rotation were found in the affected limb during ATW (Ps<0.05). Significant group interactions were noted in most of the gait variables. CONCLUSION: The results suggest that walking on a treadmill in water may show more similar gait patterns to overground walking as compared to walking in water.