Article

Segmental muscle vibration (SMV) improves motor performances in
neurological conditions, including stroke. OBJECTIVE: To determine if SMV
modifies upper limb muscular activity in chronic stroke patients performing a
reaching movement. METHODS: We randomized 22 chronic stroke patients to an
experimental group (EG; n = 12), receiving 10 sessions of exercise + 120 Hz SMV
over the biceps brachii (BB) and the flexor carpi ulnaris (FCU) muscles, or to a
control group (CG; n = 10) receiving exercise only. All subjects performed a
reaching movement with the affected side before and 4 weeks after therapy ended.
We recorded surface EMG activity of the anterior deltoid (AD), posterior deltoid
(PD), BB, triceps brachii (TB), FCU and extensor carpi radialis (ECR) muscles. We
calculated muscular onset times, modulation ratio, co-contractions and degree of
contraction. RESULTS: After SMV, onset times of the PD (p = 0.03), BB (p = 0.02)
and ECR (p = 0.04) in the EG were less anticipated than at baseline; the
modulation ratio increased in AD (p = 0.003) and BB (p = 0.01); co-contractions
decreased in the pairs BB/TB (p = 0.007), PD/BB (p = 0.004) and AD/BB (p = 0.01);
and the degree of contraction decreased in BB (p = 0.01). CONCLUSIONS: The
modulation of muscular function induced by SMV may aid to explain its action on
smoothness and coordination of movements.

Langue : ANGLAIS