Biomechanics characteristics of compensatory reactive step responding to a trip simulating perturbation while walking in young people with stroke: comparison between fallers and non-fallers

Background and purpose:
The prevalence of fall in stroke was high. The study aimed to compare the biomechanical characteristics in reactive-step during a trip simulating gait perturbation for young individual with stroke, with or without fall history, and determine the association between the biomechanics characteristics and fall.
Methods:
Ten participants of ischaemic or haemorrhagic-stroke(ICD9 430-436,mean age50.60±8.13years, independent-walker) were assessed for their response to the trip-simulation over the affected-side-leg using the acceleration-protocol(Mansi et al.,2018) while walking at their self-preferred comfortable speed on the side-split dual-belt-treadmill. Biomechanics parameters of the trunk, hips and arms relating to the reactive steps of the participants were compared between faller and non-faller group classified by self-reporting of fall history within past six-month-period.
Results:
Chronicity of stroke, age, height, weight, self-selected speed, Berg-Balance-Scale, NIH Stroke-Scale and Modified-Functional-Ambulation-Category were all comparable between the fallers(n=5,3M and 2F) and non-fallers(n=5,1M and 4F)(p>0.05). There were significant differences between fallers and non-fallers in forward trunk-flexion-angle(TFA), hip extension angle over the trip-side (affected-side)(HEA) and shoulder abduction angle over the reactive-step-side(non-affected-side)(SAA)(ps≤0.05). Whereas no between-group differences observed in the others kinematics and moment(p>0.05).
The-discriminant-function-analysis revealed that the three kinematics correctly classified 80% in this cohort. The discriminant power of these three kinematics was marginally significant (Chi-square=7.442,p=0.059) and their associations is strong (canonical-correlation=0.826). The Unstandardized-Canonical-Discriminant-function was D= -4.433+0.054TFA+0.074HEA+0.092SAA.
Conclusion:
The three specified biomechanical markers of trunk, hips and arms enables early prediction/identification of potential fallers for stratified rehabilitation and targeted fall-prevention training for individuals with higher fall-risk. The study offers a novel biomechanical approach to enhance physiotherapy care in fall-prevention for stroke-survivors.