The Effects of Whole Body Vibration (WBV) on Muscle Stiffness and Reflex Activity in People After Stroke.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 36
- Locations
- 1
- Primary Endpoint
- Muscle stiffness of paretic medial gastrocnemius
Study Overview
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.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Treatment
- Masking
- Single (Outcomes Assessor)
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Adult with a diagnosis of a hemispheric stroke >6 months,
- •Medically stable,
- •Able to stand independently for at least 1 minute and
- •Mas score >1 measured at the ankle plantar flexors.
Exclusion Criteria
- •Brainstem or cerebellar stroke,
- •Other neurological condition,
- •Serious musculoskeletal or cardiovascular disease,
- •Severe contracture of the ankle that the cannot be put in the neutral position.
- •Metal implants or recent fractures in the lower extremities or spine,
- •Fresh skin wound in lower extremities, especially popliteal fossa
- •Other severe illnesses or contraindication for exercise.
Arms & Interventions
Control
This group will stand with knee flexion 60 degrees on the same vibration platform for 60 seconds for 5 times with 60-seconds rest interval, but no vibration will be given.
Intervention: paretic leg-control (Device)
Control
This group will stand with knee flexion 60 degrees on the same vibration platform for 60 seconds for 5 times with 60-seconds rest interval, but no vibration will be given.
Intervention: non-paretic leg-control (Device)
High intensity whole body vibration
This group will stand with knee flexion 60 degrees on the same vibration platform for 60 seconds for 5 times with 60-seconds rest interval. The whole body vibration platform will be set with frequency at 30Hz and amplitude at 1.5mm.
Intervention: paretic leg-WBV (Device)
High intensity whole body vibration
This group will stand with knee flexion 60 degrees on the same vibration platform for 60 seconds for 5 times with 60-seconds rest interval. The whole body vibration platform will be set with frequency at 30Hz and amplitude at 1.5mm.
Intervention: non-paretic leg-WBV (Device)
Outcomes
Primary Outcomes
Muscle stiffness of paretic medial gastrocnemius
Time Frame: 5th minute after the intervention
Measured by Supersonic elastography with ankle in neutral position
H-reflex of paretic soleus muscle
Time Frame: 5th minute after the intervention
To measure the efficacy of synaptic transmission
H-reflex of non-paretic soleus muscle
Time Frame: 5th minute after the intervention
To measure the efficacy of synaptic transmission
Muscle stiffness of non-paretic medial gastrocnemius
Time Frame: 5th minute after the intervention
Measured by Supersonic elastography with ankle in neutral position
Secondary Outcomes
- MoviIntramuscular blood perfusion of non-paretic medial gastrocnemius muscle(4th minute after the intervention)
- Intramuscular blood perfusion of paretic medial gastrocnemius muscle(5th minute after the intervention)
- Intramuscular blood perfusion of non-paretic medial gastrocnemius muscle(5th minute after the intervention)
Investigators
Marco Yiu-Chung Pang
Professor
The Hong Kong Polytechnic University