Abnormal joint torque patterns exhibited by chronic stroke subjects while walking with a prescribed physiological gait pattern

Abstract

Background: It is well documented that individuals with chronic stroke often exhibit considerable gait impairments that significantly impact their quality of life. While stroke subjects often walk asymmetrically, we sought to investigate whether prescribing near normal physiological gait patterns with the use of the Lokomat robotic gait-orthosis could help ameliorate asymmetries in gait, specifically, promote similar ankle, knee, and hip joint torques in both lower extremities. We hypothesized that hemiparetic stroke subjects would demonstrate significant differences in total joint torques in both the frontal and sagittal planes compared to non-disabled subjects despite walking under normal gait kinematic trajectories.

Reduced knee hyperextension after wearing a robotic knee orthosis during gait training - a case study

“…This finding is similar to literature describing the use of orthosis and ambulation aids to assist patients with hemiplegia in correcting knee hyperextension by adjusting knee joint moment [16,19,20]. The use of knee AFO could decrease knee extensor moment and correct genu recurvatum during stance in patients with stroke [16].…”

“…The decrease in magnitude of the knee-extending moment could also reduce extension moment and therefore improve walking performance [20]. Lokomat improved paretic knee flexion torque during late stance and pre-swing phase to normalize gait pattern [19]. The mechanism of these changes may relate to the biomechanical properties of knee flexors and extensors as contribution to joint movement.…”

“…A hemiplegic gait pattern usually involves circumduction during the swing phase because of insufficient knee and ankle joint flexion [18]. Other rehabilitation interventions and approaches to correct circumductive gait have been published in the literature [17,19]. RKO combined treadmill walking could increase knee flexion and hip abduction to facilitate foot clearance [17].…”

“…RKO combined treadmill walking could increase knee flexion and hip abduction to facilitate foot clearance [17]. The Lokomat robot has been used to guide patients with stroke through a symmetric kinematic gait pattern to aid with foot clearance during the swing phase [19]. RKO provides dynamic assistive knee extension and resistive knee flexion.…”

Robot aided gait training and assessment : development of support strategies and assessment methods for LOPES

“…For example, stroke survivors who trained in a robotic gait trainer without hip abduction, showed considerable abduction torques in their impaired leg to overcome their lack of knee flexion during swing [177]. Although the robot enforced a gait pattern that facilitated a save walking pattern, the subjects tried to over-power the robot with their hip circumduction.…”