Weight transfer analysis in adults with hemiplegia using ankle foot orthosis

Abstract

Background: Identifying and understanding the changes in transfer of momentum that are directly affected by orthotic intervention are significant factors related to the improvement of mobility in individuals with hemiplegia. Objectives: The purpose of this investigation was to use a novel analysis technique to objectively measure weight transfer during double support (DS) in healthy individuals and individuals with hemiplegia secondary to stroke with and without an ankle foot orthosis. Study design: Prospective, Repeated measures, case-controlled trial. Methods: Participants included 25 adults with stroke-related hemiplegia >6 months using a prescribed ankle foot orthosis and 12 age-matched healthy controls. Main outcome measures included the weight transfer point timing (WTP, %DS), maximum total force timing (MTF, %DS), timing difference between WTP and MTF (MTF-WTP, %DS) and the linearity of loading (LOL, R 2 ) during the DS phase of the gait cycle. Results: The WTP and LOL were significantly different between conditions with and without the ankle foot orthosis for the affected and unaffected limb in post-stroke individuals, p 0.01. The MTF and difference in timing between MTF-WTP were significantly different during affected limb loading with and without the ankle foot orthosis in the stroke group, p 0.0001 and p ¼ 0.03, respectively. MTF, MTF-WTP and LOL were significantly different between individuals with stroke (during affected limb loading) and healthy controls (during right limb loading). Conclusions: This research established a systematic method for analysing weight transfer during walking to evaluate the effect of an ankle foot orthosis on loading during double support in hemiplegic gait. This novel method can be used to elucidate biomechanical mechanisms behind orthosis-mediated changes in gait patterns and quantify functional mobility outcomes in rehabilitation. Clinical relevanceThis novel approach to orthotic assessment will provide the clinician with needed objective evidence to select the most effective orthotic intervention to maximize functional recovery for individuals with hemiplegia secondary to stroke.

Changes in center of pressure displacement with the use of a foot drop stimulator in individuals with stroke

“…When the FDS was added, AP velocity of the CoP increased during IDS on the affected limb and resembled the AP velocity during IDS of a healthy adult. This finding is consistent with previous research indicating that a FDS added to the paretic limb during gait could improve weight acceptance (Nardone et al, 2009;Nolan and Yarossi, 2011b) and therefore provide a smoother forward progression of the CoP. Regardless of these improvements on the affected limb with FDS for individuals with stroke, the AP velocity of the CoP was still 10.9 cm/s faster throughout stance in the healthy controls.…”

“…3. Posterior movement (retropulsion) of the CoP during IDS is indicative of inefficient weight transfer on the affected limb (Nolan and Yarossi, 2011b). Further research is needed to explore how an FDS can be utilized to effectively remove retropulsion during stance and what effect that has on gait quality.…”

Effect of an EMG–FES Interface on Ankle Joint Training Combined with Real-Time Feedback on Balance and Gait in Patients with Stroke Hemiparesis

“…It can reduce the speed during walking and cause shifting or confusion while embracing one's body weight. Furthermore, foot drop may result in inefficiency and instability during walking [3]. Foot drop limits the appropriate toe clearance during the swing phase.…”

Alterations in Spectral Attributes of Surface Electromyograms after Utilization of a Foot Drop Stimulator during Post-Stroke Gait

“…Stroke is one of the leading causes of serious and long-term disability, and foot drop is one of the most common disabling impairments resulting from hemiplegia due to stroke ( 1 ). Foot drop characterized by weakness and/or lack of voluntary control in the ankle and toe dorsiflexor muscles ( 2 ) can result in gait related deficiencies (decreased speed, a disruption in weight acceptance and transfer, asymmetry and instability), further limiting the activities of daily living ( 3 , 4 ). The application of an ankle foot orthosis (AFO) to compensate for foot drop throughout the gait has been the common modality of treatment.…”