Article

Focal vibration has been studied for its ability to reduce spasticity
in patients with upper motor neuron lesions, but adequate stimulation parameters
remain unclear. Focal muscle vibration with adequate parameters may facilitate
gait rehabilitation in patients with lower limb spasticity.
OBJECTIVE: To
determine focal muscle vibration parameters that effectively inhibit the H-reflex
of the gastrocnemius in healthy subjects. DESIGN: A proof-of-concept exploratory study. SETTING: University hospital laboratory. SUBJECTS: Thirteen healthy volunteers. METHODS: Focal muscle vibrations of 40, 80, and 120 Hz and amplitudes
of 0.1, 0.3, and 0.5 mm were tested on the calf muscles of 10 healthy subjects,
respectively. The H-reflex and M-response were recorded baseline, during
vibration, and after vibration for each stimulation parameter.
The mean vibratory
inhibition index (VII) during vibration, the maximum amplitude of the H-reflex
and M-response (Hmax and Mmax), minimal onset latency of the H-reflex, and the
ratio of Hmax to Mmax (HMR) at each time point were measured. RESULTS: No
significant difference was found among mean VIIs at 40, 80, and 120 Hz in the
healthy subjects. However, a relatively consistent reduction of Hmax and HMR was
observed at 80 Hz. Mean VIIs at 0.3 and 0.5 mm were significantly lower than that
at 0.1 mm (P < .001). CONCLUSION: This study suggests that focal muscle vibration
may be an adjuvant therapy during gait rehabilitation in patients with calf
muscle spasticity. Focal vibration at 80 Hz and 0.3 mm amplitude applied to the
gastrocnemius effectively inhibits the segmental reflex pathway.
A future
clinical trial on this topic is warranted. LEVEL OF EVIDENCE: II.
CI - Copyright (c) 2016 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS