当前位置： SCI文献检索 > JOURNAL OF NEUROPHYSIOLOGY期刊下所有文献 > Lack of on-going adaptations in the soleus muscle activity during walking in patients affected by large-fiber neuropathy.

Lack of on-going adaptations in the soleus muscle activity during walking in patients affected by large-fiber neuropathy.

Abstract：

:The aim of this study was to investigate the contribution of feedback from large-diameter sensory fibers to the adaptation of soleus muscle activity after small ankle trajectory modifications during human walking. Small-amplitude and slow-velocity ankle dorsiflexion enhancements and reductions were applied during the stance phase of the gait cycle to mimic the normal variability of the ankle trajectory during walking. Patients with demyelination of large sensory fibers (Charcot-Marie-Tooth type 1A and antibodies to myelin-associated glycoprotein neuropathy) and age-matched controls participated in this study. The patients had absent light-touch sense in the toes and feet and absent quadriceps and Achilles tendon reflexes, indicating functional loss of large sensory fibers. Moreover, their soleus stretch reflex response consisted of a single electromyographic (EMG) burst with delayed onset and longer duration (P < 0.01) than the short- and medium-latency reflex responses observed in healthy subjects. In healthy subjects, the soleus EMG gradually increased or decreased when the ankle dorsiflexion was, respectively, enhanced or reduced. In the patients, the soleus EMG increased during the dorsiflexion enhancements; however, the velocity sensitivity of this response was decreased compared with the healthy volunteers. When the dorsiflexion was reduced, the soleus EMG was unchanged. These results indicate that the enhancement of the soleus EMG is mainly sensitive to feedback from primary and secondary muscle spindle afferents and that the reduction may be mediated by feedback from the group Ib pathways. This study provides evidence for the role of sensory feedback in the continuous adaptation of the soleus activity during the stance phase of human walking.

journal_name

J Neurophysiol

journal_title

Journal of neurophysiology

authors

Mazzaro N,Grey MJ,Sinkjaer T,Andersen JB,Pareyson D,Schieppati M

doi

10.1152/jn.01071.2004

subject

Has Abstract

pub_date

2005-06-01 00:00:00

pages

3075-85

issue

eissn

0022-3077

issn

1522-1598

pii

01071.2004

journal_volume

pub_type

杂志文章

在线工具

Lack of on-going adaptations in the soleus muscle activity during walking in patients affected by large-fiber neuropathy.