Article

Spasticity is a common sequela of upper motor neuron pathology, such
as cerebrovascular diseases and cerebral palsy. Intervention for spasticity of
the ankle plantarflexors in physical therapy may include tone-inhibiting casting
and/or orthoses for the ankle and foot. However, the physiological mechanism of
tone reduction by such orthoses remains unclarified.
OBJECTIVE: To investigate
the electrophysiologic effects of tone-inhibiting insoles in stroke subjects with
hemiparesis by measuring changes in reciprocal Ia inhibition (RI) in the ankle
plantarflexor. DESIGN: An interventional before-after study. SETTING: Acute
stroke unit or ambulatory rehabilitation clinic of a university hospital in
Japan. PARTICIPANTS: Ten subjects (47-84 years) with hemiparesis and 10 healthy
male control subjects (31-59 years) were recruited. METHODS: RI of the spastic
soleus in response to the electrical stimulation of the deep peroneal nerve was
evaluated by stimulus-locked averaging of rectified electromyography (EMG) of the
soleus while subjects were standing. MAIN OUTCOME MEASUREMENTS: The magnitude of
RI, defined as the ratio of the lowest to the baseline amplitude of the rectified
EMG at approximately 40 milliseconds after stimulation, was measured while
subjects were standing with and without the tone-inhibiting insole on the
hemiparesis side. RESULTS: Enhancement of EMG reduction with the tone-inhibiting
insole was significant (P < .05) in the subjects with hemiparesis, whereas no
significant changes were found in controls. CONCLUSION:
Tone-inhibiting insoles
enhanced RI of the soleus in subjects after stroke, which might enhance standing
stability by reducing unfavorable ankle plantarflexion tone.
LEVEL OF EVIDENCE: III.
CI - Copyright (c) 2018 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS