Article

Repetitive peripheral magnetic stimulation (RPMS) is a painless and
noninvasive method to produce afferents via the depolarization of the peripheral
nervous system. A few studies tested RPMS after-effects on cerebral plasticity
and motor recovery in stroke individuals, but evidences remain limited.
This study aimed to explore whether RPMS could mediate improvements
in corticomotor and clinical outcomes associated with ankle impairments in
chronic stroke. METHODS: Eighteen subjects with chronic stroke were randomly
allocated to RPMS or sham group and compared to 14 healthy subjects. Stimulation
was applied over the paretic tibialis anterior (TA). Ankle impairments on the
paretic side and ipsilesional TA cortical motor representation were tested
clinically and by transcranial magnetic stimulation (TMS), respectively. RESULTS:
In the RPMS group, ankle dorsiflexion mobility and maximal isometric strength
increased and resistance to plantar flexor stretch decreased. The magnitude of
change seemed to be related to cortical and corticospinal integrity. Sham
stimulation yielded no effect. Changes in TMS outcome and their relationships
with clinical improvements were limited. CONCLUSIONS: RPMS improved ankle
impairments in chronic stroke likely by a dynamic influence of sensory inputs on
synaptic plasticity. The neurophysiological mechanisms potentially underlying the
clinical effects are unclear. More studies are warranted to test the spinal and
hemispheric changes responsible for the clinical improvements with emphasis on
circuits spared by the lesion.

Langue : ANGLAIS