Stroke
Conditions
Keywords
Muscle Stiffness, Ultrasound elastography, H-reflex, Whole body vibration, blood perfusion
Brief summary
Spastic hypertonia is common after stroke. Whole-body vibration (WBV) is known to have modulatory effects of muscle reflex activity and blood flow in other populations and thus have potential applications in the management of spastic hypertonia post-stroke. This study aims to investigate the acute effect of WBV on leg muscle H-reflex, stiffness, and blood perfusion in people with chronic stroke.
Detailed description
Spastic hypertonia is common after stroke. Whole-body vibration (WBV) is known to have modulatory effects of muscle reflex activity and blood flow in other populations and thus have potential applications in management of spastic hypertonia post-stroke. However, the potential effects of WBV on leg muscle stiffness in stroke rehabilitation remains unknown. Scientific evidence is warranted to fill the knowledge gap. Purpose This study aims to investigate the acute effect of WBV on leg muscle H-reflex, stiffness and blood perfusion in people with chronic stroke. Methods Individuals with chronic stroke will be recruited from community self-help groups and existing patient database. Relevant information (e.g. demographic information, medical history) will be obtained from medical records and subject interviews. Each subject will have to fulfill the following inclusion criteria: (1) diagnosis of chronic stroke, (2) community-dwelling, (3) able to follow simple verbal instructions. Exclusion criteria are: (1) other diagnoses of neurological conditions, (2) significant musculoskeletal conditions (e.g. amputations), (3) metal implants in the lower extremity or spine, (4) recent fracture in the lower extremity, (5) diagnosis of osteoporosis, (6) vestibular disorders, (7) peripheral vascular disease, and (11) other serious illnesses or contraindications to exercise. This is a single-blinded randomized within-patient cross-over study. Each participant was evaluated for the soleus H-reflex, stiffness and blood perfusion of the medial gastrocnemius (MG) using ultrasound on both sides before and after either a 5-minute WBV intervention (30 Hertz, 1.5mm, knee flexed 60 degrees) or a no-WBV condition (5 minutes). The measurements were performed at baseline and every 1-min post-intervention up to 5 minutes. The outcomes generated included the soleus H/M ratio, shear modulus and vascular index (VI) of the MG muscle.
Interventions
DEVICEparetic leg-control
standing on the vibration platform, with no vibration signals delivered.
DEVICEparetic leg-WBV
standing on the vibration platform, with WBV at 30Hz, 1.5mm.
DEVICEnon-paretic leg-control
standing on the vibration platform, with no vibration signals delivered.
DEVICEnon-paretic leg-WBV
standing on the vibration platform, with WBV at 30Hz, 1.5mm.
Sponsors
The Hong Kong Polytechnic University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Adult with a diagnosis of a hemispheric stroke \>6 months, 2. Medically stable, 3. Able to stand independently for at least 1 minute and 4. Mas score \>1 measured at the ankle plantar flexors.
Exclusion criteria
1. Brainstem or cerebellar stroke, 2. Other neurological condition, 3. Serious musculoskeletal or cardiovascular disease, 4. Severe contracture of the ankle that the cannot be put in the neutral position. 5. Metal implants or recent fractures in the lower extremities or spine, 6. Fresh skin wound in lower extremities, especially popliteal fossa 7. Other severe illnesses or contraindication for exercise.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| H-reflex of non-paretic soleus muscle | Immediately before the intervention | To measure the efficacy of synaptic transmission |
| H-reflex of paretic soleus muscle | Immediately before the intervention | To measure the efficacy of synaptic transmission |
| Muscle stiffness of paretic medial gastrocnemius | Immediately before the intervention | Measured by Supersonic elastography with ankle in neutral position |
| Muscle stiffness of non-paretic medial gastrocnemius | Immediately before the intervention | Measured by Supersonic elastography with ankle in neutral position |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| MoviIntramuscular blood perfusion of non-paretic medial gastrocnemius muscle | 4th minute after the intervention | Measured by power Doppler ultrasound |
| Intramuscular blood perfusion of paretic medial gastrocnemius muscle | Immediately before the intervention | Measured by power Doppler ultrasound |
| Intramuscular blood perfusion of non-paretic medial gastrocnemius muscle | Immediately before the intervention | Measured by power Doppler ultrasound |
Other
| Measure | Time frame | Description |
|---|---|---|
| Fugl-Meyer Assessment of Motor Recovery after Stroke--lower extremities | Immediately before the intervention | Evaluates and measures motor recovery in post-stroke hemiplegic patients |
| Brief Balance Evaluation Systems Test | Immediately before the intervention | — |
Countries
Hong Kong
Outcome results
None listed