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Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis

BACKGROUND: Gait impairment is a common complication of multiple sclerosis (MS). Gait limitations such as limited hip flexion, foot drop, and knee hyperextension often require external devices like crutches, canes, and orthoses. The effects of mobility-assistive technologies (MATs) prescribed to peo...

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Autores principales: Neuman, Ross M., Shearin, Staci M., McCain, Karen J., Fey, Nicholas P.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8237473/
https://www.ncbi.nlm.nih.gov/pubmed/34176484
http://dx.doi.org/10.1186/s12984-021-00891-7
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author Neuman, Ross M.
Shearin, Staci M.
McCain, Karen J.
Fey, Nicholas P.
author_facet Neuman, Ross M.
Shearin, Staci M.
McCain, Karen J.
Fey, Nicholas P.
author_sort Neuman, Ross M.
collection PubMed
description BACKGROUND: Gait impairment is a common complication of multiple sclerosis (MS). Gait limitations such as limited hip flexion, foot drop, and knee hyperextension often require external devices like crutches, canes, and orthoses. The effects of mobility-assistive technologies (MATs) prescribed to people with MS are not well understood, and current devices do not cater to the specific needs of these individuals. To address this, a passive unilateral hip flexion-assisting orthosis (HFO) was developed that uses resistance bands spanning the hip joint to redirect energy in the gait cycle. The purpose of this study was to investigate the short-term effects of the HFO on gait mechanics and muscle activation for people with and without MS. We hypothesized that (1) hip flexion would increase in the limb wearing the device, and (2) that muscle activity would increase in hip extensors, and decrease in hip flexors and plantar flexors. METHODS: Five healthy subjects and five subjects with MS walked for minute-long sessions with the device using three different levels of band stiffness. We analyzed peak hip flexion and extension angles, lower limb joint work, and muscle activity in eight muscles on the lower limbs and trunk. Single-subjects analysis was used due to inter-subject variability. RESULTS: For subjects with MS, the HFO caused an increase in peak hip flexion angle and a decrease in peak hip extension angle, confirming our first hypothesis. Healthy subjects showed less pronounced kinematic changes when using the device. Power generated at the hip was increased in most subjects while using the HFO. The second hypothesis was not confirmed, as muscle activity showed inconsistent results, however several subjects demonstrated increased hip extensor and trunk muscle activity with the HFO. CONCLUSIONS: This exploratory study showed that the HFO was well-tolerated by healthy subjects and subjects with MS, and that it promoted more normative kinematics at the hip for those with MS. Future studies with longer exposure to the HFO and personalized assistance parameters are needed to understand the efficacy of the HFO for mobility assistance and rehabilitation for people with MS. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12984-021-00891-7.
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spelling pubmed-82374732021-06-29 Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis Neuman, Ross M. Shearin, Staci M. McCain, Karen J. Fey, Nicholas P. J Neuroeng Rehabil Research BACKGROUND: Gait impairment is a common complication of multiple sclerosis (MS). Gait limitations such as limited hip flexion, foot drop, and knee hyperextension often require external devices like crutches, canes, and orthoses. The effects of mobility-assistive technologies (MATs) prescribed to people with MS are not well understood, and current devices do not cater to the specific needs of these individuals. To address this, a passive unilateral hip flexion-assisting orthosis (HFO) was developed that uses resistance bands spanning the hip joint to redirect energy in the gait cycle. The purpose of this study was to investigate the short-term effects of the HFO on gait mechanics and muscle activation for people with and without MS. We hypothesized that (1) hip flexion would increase in the limb wearing the device, and (2) that muscle activity would increase in hip extensors, and decrease in hip flexors and plantar flexors. METHODS: Five healthy subjects and five subjects with MS walked for minute-long sessions with the device using three different levels of band stiffness. We analyzed peak hip flexion and extension angles, lower limb joint work, and muscle activity in eight muscles on the lower limbs and trunk. Single-subjects analysis was used due to inter-subject variability. RESULTS: For subjects with MS, the HFO caused an increase in peak hip flexion angle and a decrease in peak hip extension angle, confirming our first hypothesis. Healthy subjects showed less pronounced kinematic changes when using the device. Power generated at the hip was increased in most subjects while using the HFO. The second hypothesis was not confirmed, as muscle activity showed inconsistent results, however several subjects demonstrated increased hip extensor and trunk muscle activity with the HFO. CONCLUSIONS: This exploratory study showed that the HFO was well-tolerated by healthy subjects and subjects with MS, and that it promoted more normative kinematics at the hip for those with MS. Future studies with longer exposure to the HFO and personalized assistance parameters are needed to understand the efficacy of the HFO for mobility assistance and rehabilitation for people with MS. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12984-021-00891-7. BioMed Central 2021-06-27 /pmc/articles/PMC8237473/ /pubmed/34176484 http://dx.doi.org/10.1186/s12984-021-00891-7 Text en © The Author(s) 2021 https://creativecommons.org/licenses/by/4.0/Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/ (https://creativecommons.org/publicdomain/zero/1.0/) ) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
spellingShingle Research
Neuman, Ross M.
Shearin, Staci M.
McCain, Karen J.
Fey, Nicholas P.
Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title_full Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title_fullStr Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title_full_unstemmed Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title_short Biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
title_sort biomechanical analysis of an unpowered hip flexion orthosis on individuals with and without multiple sclerosis
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8237473/
https://www.ncbi.nlm.nih.gov/pubmed/34176484
http://dx.doi.org/10.1186/s12984-021-00891-7
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