The relation between Ashworth scale scores and the excitability of the alpha motor neurones in patients with post-stroke muscle spasticity.

AMO Bakheit, VA Maynard, J Curnow, N Hudson, S Kodapala

Research output: Contribution to journalArticlepeer-review

Abstract

BACKGROUND: The modified Ashworth scale (MAS) is the most widely used method for assessing muscle spasticity in clinical practice and research. However, the validity of this scale has been challenged. OBJECTIVES: To compare the MAS with objective neurophysiological tests of spasticity. METHODS: The MAS was recorded in patients with post-stroke lower limb muscle spasticity and correlated with the excitability of the alpha motor neurones. The latter was evaluated by measuring the latency of the Hoffmann reflex (H reflex) and the ratio of the amplitude of the maximum H reflex (H(max)) to that of the compound action motor potential of the soleus muscle (M(max)). RESULTS: Data on 24 randomly recruited patients were analysed. Patients were divided into two groups according to their MAS score: 14 had a MAS score of 1 (group A) and 10 scored 2 (group B). The two groups were comparable with respect to age and sex, but in group A there was a longer period since the stroke. The H reflex latency was reduced and the H(max):M(max) ratio was increased in both groups. The H(max):M(max) ratio values were higher for group B but the differences were not statistically significant. CONCLUSIONS: There is a relation between the MAS scores and alpha motor neurone excitability, although it is not linear. This suggests that the MAS measures muscle hypertonia rather than spasticity.
Original languageEnglish
Pages (from-to)646-648
Number of pages0
JournalJ Neurol Neurosurg Psychiatry
Volume74
Issue number5
DOIs
Publication statusPublished - May 2003

Keywords

  • Action Potentials
  • Adult
  • Aged
  • 80 and over
  • Female
  • H-Reflex
  • Humans
  • Lower Extremity
  • Male
  • Middle Aged
  • Motor Neurons
  • Muscle Spasticity
  • Muscle
  • Skeletal
  • Reaction Time
  • Reproducibility of Results
  • Severity of Illness Index
  • Stroke

Fingerprint

Dive into the research topics of 'The relation between Ashworth scale scores and the excitability of the alpha motor neurones in patients with post-stroke muscle spasticity.'. Together they form a unique fingerprint.

Cite this