Reduction of common synaptic drive to ankle dorsiflexor motoneurons during walking in patients with spinal cord lesion

N.L. Hansen, B.A. Conway, D.M. Halliday, S. Hansen, H.S. Pyndt, F. Biering-Sorensen, J.B. Nielsen

    Research output: Contribution to journalArticle

    72 Citations (Scopus)

    Abstract

    It is possible to obtain information about the synaptic drive to motoneurons during walking by analyzing motor-unit coupling in the time and frequency domains. The purpose of the present study was to compare motor-unit coupling during walking in healthy subjects and patients with incomplete spinal cord lesion to obtain evidence of differences in the motoneuronal drive that result from the lesion. Such information is of importance for development of new strategies for gait restoration. Twenty patients with incomplete spinal cord lesion (SCL) participated in the study. Control experiments were performed in 11 healthy subjects. In all healthy subjects, short-term synchronization was evident in the discharge of tibialis anterior (TA) motor units during the swing phase of treadmill walking. This was identified from the presence of a narrow central peak in cumulant densities constructed from paired EMG recordings and from the presence of significant coherence between these signals in the 10- to 20-Hz band. Such indicators of short-term synchrony were either absent or very small in the patient group. The relationship between the amount of short-term synchrony and the magnitude of the 10- to 20-Hz coherence in the patients is discussed in relation to gait ability. It is suggested that supraspinal drive to the spinal cord is responsible for short-term synchrony and coherence in the 10- to 20-Hz frequency band during walking in healthy subjects. Absence or reduction of these features may serve as physiological markers of impaired supraspinal control of gait in SCL patients. Such markers could have diagnostic and prognostic value in relation to the recovery of locomotion in patients with central motor lesions.
    LanguageEnglish
    Pages934-942
    Number of pages8
    JournalJournal of Neurophysiology
    Volume94
    Issue number2
    DOIs
    Publication statusPublished - 2005

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    Motor Neurons
    Ankle
    Walking
    Spinal Cord
    Healthy Volunteers
    Gait
    Locomotion

    Keywords

    • motor neurons
    • bioengineering
    • biomechanics
    • walking
    • ankle
    • spinal cord

    Cite this

    Hansen, N.L. ; Conway, B.A. ; Halliday, D.M. ; Hansen, S. ; Pyndt, H.S. ; Biering-Sorensen, F. ; Nielsen, J.B. / Reduction of common synaptic drive to ankle dorsiflexor motoneurons during walking in patients with spinal cord lesion. In: Journal of Neurophysiology. 2005 ; Vol. 94, No. 2. pp. 934-942.
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    Reduction of common synaptic drive to ankle dorsiflexor motoneurons during walking in patients with spinal cord lesion. / Hansen, N.L.; Conway, B.A.; Halliday, D.M.; Hansen, S.; Pyndt, H.S.; Biering-Sorensen, F.; Nielsen, J.B.

    In: Journal of Neurophysiology, Vol. 94, No. 2, 2005, p. 934-942.

    Research output: Contribution to journalArticle

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    AU - Hansen, N.L.

    AU - Conway, B.A.

    AU - Halliday, D.M.

    AU - Hansen, S.

    AU - Pyndt, H.S.

    AU - Biering-Sorensen, F.

    AU - Nielsen, J.B.

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    KW - ankle

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