Cargando…
Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke
BACKGROUND: Extensor synergy is often observed in the paretic leg of stroke patients. Extensor synergy consists of an abnormal stereotyped co-activation of the leg extensors as patients attempt to move. As a component of this synergy, the simultaneous activation of knee and ankle extensors in the pa...
Autores principales: | , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
BioMed Central
2014
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4271343/ https://www.ncbi.nlm.nih.gov/pubmed/25343962 http://dx.doi.org/10.1186/1743-0003-11-148 |
_version_ | 1782349586700959744 |
---|---|
author | Dyer, Joseph-Omer Maupas, Eric de Andrade Melo, Sibele Bourbonnais, Daniel Nadeau, Sylvie Forget, Robert |
author_facet | Dyer, Joseph-Omer Maupas, Eric de Andrade Melo, Sibele Bourbonnais, Daniel Nadeau, Sylvie Forget, Robert |
author_sort | Dyer, Joseph-Omer |
collection | PubMed |
description | BACKGROUND: Extensor synergy is often observed in the paretic leg of stroke patients. Extensor synergy consists of an abnormal stereotyped co-activation of the leg extensors as patients attempt to move. As a component of this synergy, the simultaneous activation of knee and ankle extensors in the paretic leg during stance often affects gait pattern after stroke. The mechanisms involved in extensor synergy are still unclear. The first objective of this study is to compare the co-activation of knee and ankle extensors during the stance phase of gait between stroke and healthy individuals. The second objective is to explore whether this co-activation is related to changes in heteronymous spinal modulations between quadriceps and soleus muscles on the paretic side in post-stroke individuals. METHODS: Thirteen stroke patients and ten healthy individuals participated in gait and heteronymous spinal modulation evaluations. Co-activation was measured using peak EMG activation intervals (PAI) and co-activation amplitude indexes (CAI) between knee and ankle extensors during the stance phase of gait in both groups. The evaluation of heteronymous spinal modulations was performed on the paretic leg in stroke participants and on one leg in healthy participants. This evaluation involved assessing the early facilitation and later inhibition of soleus voluntary EMG induced by femoral nerve stimulation. RESULTS: All PAI were lower and most CAI were higher on the paretic side of stroke participants compared with the co-activation indexes among control participants. CAI and PAI were moderately correlated with increased heteronymous facilitation of soleus on the paretic side in stroke individuals. CONCLUSIONS: Increased co-activation of knee and ankle extensors during gait is related to changes in intersegmental facilitative pathways linking quadriceps to soleus on the paretic side in stroke individuals. Malfunction of intersegmental pathways could contribute to abnormal timing of leg extensors during the stance phase of gait in hemiparetic individuals. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1743-0003-11-148) contains supplementary material, which is available to authorized users. |
format | Online Article Text |
id | pubmed-4271343 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2014 |
publisher | BioMed Central |
record_format | MEDLINE/PubMed |
spelling | pubmed-42713432014-12-20 Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke Dyer, Joseph-Omer Maupas, Eric de Andrade Melo, Sibele Bourbonnais, Daniel Nadeau, Sylvie Forget, Robert J Neuroeng Rehabil Research BACKGROUND: Extensor synergy is often observed in the paretic leg of stroke patients. Extensor synergy consists of an abnormal stereotyped co-activation of the leg extensors as patients attempt to move. As a component of this synergy, the simultaneous activation of knee and ankle extensors in the paretic leg during stance often affects gait pattern after stroke. The mechanisms involved in extensor synergy are still unclear. The first objective of this study is to compare the co-activation of knee and ankle extensors during the stance phase of gait between stroke and healthy individuals. The second objective is to explore whether this co-activation is related to changes in heteronymous spinal modulations between quadriceps and soleus muscles on the paretic side in post-stroke individuals. METHODS: Thirteen stroke patients and ten healthy individuals participated in gait and heteronymous spinal modulation evaluations. Co-activation was measured using peak EMG activation intervals (PAI) and co-activation amplitude indexes (CAI) between knee and ankle extensors during the stance phase of gait in both groups. The evaluation of heteronymous spinal modulations was performed on the paretic leg in stroke participants and on one leg in healthy participants. This evaluation involved assessing the early facilitation and later inhibition of soleus voluntary EMG induced by femoral nerve stimulation. RESULTS: All PAI were lower and most CAI were higher on the paretic side of stroke participants compared with the co-activation indexes among control participants. CAI and PAI were moderately correlated with increased heteronymous facilitation of soleus on the paretic side in stroke individuals. CONCLUSIONS: Increased co-activation of knee and ankle extensors during gait is related to changes in intersegmental facilitative pathways linking quadriceps to soleus on the paretic side in stroke individuals. Malfunction of intersegmental pathways could contribute to abnormal timing of leg extensors during the stance phase of gait in hemiparetic individuals. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1743-0003-11-148) contains supplementary material, which is available to authorized users. BioMed Central 2014-10-24 /pmc/articles/PMC4271343/ /pubmed/25343962 http://dx.doi.org/10.1186/1743-0003-11-148 Text en © Dyer et al.; licensee BioMed Central Ltd. 2014 This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. |
spellingShingle | Research Dyer, Joseph-Omer Maupas, Eric de Andrade Melo, Sibele Bourbonnais, Daniel Nadeau, Sylvie Forget, Robert Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title | Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title_full | Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title_fullStr | Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title_full_unstemmed | Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title_short | Changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
title_sort | changes in activation timing of knee and ankle extensors during gait are related to changes in heteronymous spinal pathways after stroke |
topic | Research |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4271343/ https://www.ncbi.nlm.nih.gov/pubmed/25343962 http://dx.doi.org/10.1186/1743-0003-11-148 |
work_keys_str_mv | AT dyerjosephomer changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke AT maupaseric changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke AT deandrademelosibele changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke AT bourbonnaisdaniel changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke AT nadeausylvie changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke AT forgetrobert changesinactivationtimingofkneeandankleextensorsduringgaitarerelatedtochangesinheteronymousspinalpathwaysafterstroke |