Several studies have recently tested the use of muscle vibration for the rehabilitation of patients after a stroke. When applied in a repeated and focused manner, this vibration appears to promote the recovery of functional capacities through the mechanisms of neuromuscular plasticity. These results are encouraging, showing in particular a significant decrease in spasticity in post-stroke patients in the chronic phase (> 6 months after stroke), on the upper and/or lower limbs. However, very few studies have been done on this type of early intervention. Muscle vibration may therefore be an innovative therapy to complement the care that is currently offered in the acute and subacute phase of post-stroke rehabilitation.

Moreover, brain plasticity after a stroke is particularly high in the 3 months after the accident, but the vast majority of studies having evaluated the impact of vibration in a chronic phase (> 12 months post-stroke). It is likely, however, that the influence of vibration, particularly on brain plasticity, is increased in the acute or subacute phase (first 6 months). To date, the effect of vibration on spinal cord or cortical plasticity has not been quantified in the acute or subacute phase. This is why the second part of this project (phase 2) aims to systematically evaluate and quantify the neuroplastic and functional effects of post-stroke vibration in the early phase.

Phase 1 - Validation of a method for measuring spasticity (upper limb) with an isokinetic dynamometer 32 patients with ischemic and/or hemorrhagic stroke (> 3 months after stroke)

Phase 2 - Use of this objective technique to measure the effect of a muscle vibration protocol to limit the onset of spasticity in a population of 100 patients following a stroke, in the acute or subacute phase (< 6 weeks post-stroke) in a randomized trial:

• intervention group: usual rehabilitation + muscle vibrations
• control group: usual rehabilitation + placebo vibrations

Inclusion Criteria:

Phase 1:

• Adult patient,
• Medically stable on medical assessment, with no contraindications to stroke rehabilitation management management (no medical problems or acute intercurrent medical events),
• Have had an ischemic and/or hemorrhagic stroke (> 3 months post-stroke), impacting the motor skills of the upper limbs,
• 1 ≤ MAS < 4 on elbow or wrist flexors,
• Having given oral consent.

Phase 2:

• Adult patient > 18 years old,
• Able to follow a rehabilitation program on medical opinion (no medical issues or acute intercurrent medical events),
• First stroke ever < 6 weeks, confirmed by imaging,
• Hemiparesis or hemiplegia of the upper limb (FMA-UE score < 48), particularly in the wrist and elbow flexors,
• Requiring inpatient or outpatient hospitalization in a rehabilitation center,
• Having given oral consent.

Exclusion Criteria:

• Phases 1 and 2:
• Significant pain on mobilization of the wrist or elbow (VAS > 5/10),
• Presence of other neurological, muscular or osteoarticular conditions altering upper limb function,
• Apparent wound, which may postpone inclusion, or very fragile skin,
• Significant cognitive impairments: inability to understand simple instructions or give consent of any kind (not included if: LAST scores < 5/7 in comprehension, and if YES/NO answers are unreliable),
• Not covered by national health insurance,
• Being pregnant or breastfeeding,
• Being under guardianship or curatorship.
• Person subject to a measure of legal protection

The study team policy is about to share and collaborate with other research teams upon reasonable request for access to study data. Expressions of interest in access to study data, addressed to the corresponding author, will be considered and data de-identified at group or individual level may be shared as appropriate. A data transfer agreement will then be drawn up. The study dataset will be available at the end of the study, once the database is frozen. Sharing the database will be made available between interested parts with a data sharing agreement contract.

after publication of the lead article