Interlimb influences on paretic leg function in poststroke hemiparesis

S. A. Kautz, Carolynn Patten

Research output: Contribution to journalArticle

60 Scopus citations

Abstract

After stroke, paretic leg motor impairment is typically viewed as a unilateral control deficit. However, much of the neural circuitry controlling normal leg function is organized bilaterally to produce coordinated, task-specific activity in the two legs. Thus, as a result of contralesional neural control processes, paretic leg motor pattern generation may be substantially influenced by the nonparetic leg sensorimotor state during bilateral lower limb tasks. Accordingly, we investigated whether different paretic leg motor patterns are observed during mechanically equivalent bilateral and unilateral tasks and, if so, whether nonparetic leg participation improved or exacerbated paretic leg coordination deficits. A pedaling apparatus that mechanically decoupled the legs was used to present subjects with increasingly complex bi- and unilateral motor tasks: isometric force generation, discrete movement, and pedaling. Bilateral electromyographic and pedal force data were collected from 21 persons with chronic poststroke hemiparesis and 11 similarly aged controls. During isometric force generation and discrete movements, nonparetic leg influences on paretic leg coordination were similar and not markedly different from interlimb influences in controls. In bilateral pedaling, however, interlimb influences differed from controls such that paretic leg coordination deficits were exacerbated. During pedaling movements, the suppression of interlimb influences similar to those observed in isometric and discrete movement may occur in controls but may be disrupted in hemiparesis. We suggest that the coupling of pattern generation between the two legs may result in greater, albeit more impaired, paretic leg motor output during bilateral pedaling than during unilateral pedaling.

Original languageEnglish (US)
Pages (from-to)2460-2473
Number of pages14
JournalJournal of Neurophysiology
Volume93
Issue number5
DOIs
StatePublished - May 1 2005
Externally publishedYes

ASJC Scopus subject areas

  • Neuroscience(all)
  • Physiology

Fingerprint Dive into the research topics of 'Interlimb influences on paretic leg function in poststroke hemiparesis'. Together they form a unique fingerprint.

  • Cite this