Journal article
How persons with transtibial amputation regulate lateral stepping while walking in laterally destabilizing environments
Gait & posture, Vol.83, pp.88-95
01/2021
DOI: 10.1016/j.gaitpost.2020.09.031
PMCID: PMC7755758
PMID: 33099136
Abstract
Persons with lower limb amputation often experience decreased physical capacity, difficulty walking, and increased fall risk. To either prevent or recover from a loss of balance, one must effectively regulate their stepping movements. It is therefore critical to identify how well persons with amputation regulate stepping. Here, we used a multi-objective control framework based on Goal Equivalent Manifolds to identify how persons with transtibial amputation (TTA) regulate lateral stepping while walking without and with lateral perturbations.
When walking in destabilizing environments, do otherwise healthy persons with TTA exhibit greater difficulty regulating lateral stepping due to impaired control? Or do they instead continue to use similar strategies to regulate lateral stepping despite their amputation?
Eight persons with unilateral TTA and thirteen able-bodied (AB) controls walked in a virtual environment under three conditions: no perturbations, laterally oscillating visual field, and laterally oscillating treadmill platform. We analyzed step-to-step time series of step widths and absolute lateral body positions. We computed means, standard deviations and Detrended Fluctuation Analysis scaling exponents for each time series and computed how much participants directly corrected step width and position deviations at each step. We compared our results to computational predictions to identify the underlying causes of our experimental findings.
All participants exhibited significantly increased variability, decreased scaling exponents, and tighter direct control when perturbed. Simulations from our stepping regulation models revealed that people responded to the increased variability produced by the imposed perturbations by tightening their control of both step width and lateral position. Participants with TTA exhibited only a few minor differences from AB in lateral stepping regulation, even when subjected to substantially destabilizing lateral perturbations.
Since control of stepping is intrinsically multi-objective, developing effective interventions to reduce fall risk in persons with amputation will likely require strategies that adopt multi-objective approaches.
Details
- Title: Subtitle
- How persons with transtibial amputation regulate lateral stepping while walking in laterally destabilizing environments
- Creators
- Jonathan B Dingwell - The University of Texas at AustinJoseph P Cusumano - Pennsylvania State UniversityJonathan H Rylander - San Antonio Military Medical CenterJason M Wilken - San Antonio Military Medical Center
- Resource Type
- Journal article
- Publication Details
- Gait & posture, Vol.83, pp.88-95
- DOI
- 10.1016/j.gaitpost.2020.09.031
- PMID
- 33099136
- PMCID
- PMC7755758
- ISSN
- 0966-6362
- eISSN
- 1879-2219
- Grant note
- R01 HD059844 / NICHD NIH HHS
- Language
- English
- Date published
- 01/2021
- Academic Unit
- Physical Therapy and Rehabilitation Science
- Record Identifier
- 9984294948502771
Metrics
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