None listed
Conditions
Brief summary
Stroke affects approximately 56,000 New Zealanders at any point in time. The majority of patients regain their ability to walk but have difficulty initiating stable gait. This instability increases the likelihood of falls, and diminishes the patient’s confidence to walk in the community. Research suggests this instability is caused by poor balance and weakness in the affected leg, plus abnormal commands descending from the brain to the spinal cord that alter the timing of muscle activations in the legs just prior to stepping off. This latter abnormality is the subject of the proposed research. The experiments will determine if safe, painless and weak electrical stimulation administered to the brain through the scalp can restore the generation of normal brain commands and increase stability of gait initiation in stroke survivors. Age-similar healthy control subjects will be included in the study to aid our understanding of the effects of the brain stimulation, and of the mechanisms driving improved stability. Research outcomes are expected to inform the development of new walking-related therapies. The study will also seek to identify patient characteristics that would guide the future delivery of an enhanced therapy on an individualised patient basis.
Interventions
Two intervention arms in a cross-over design: once only sessions where either active or sham anodal transcranial direct current stimulation is delivered to the lesioned lower limb motor cortex from a Phoresor II stimulator (Model PM850; IOMED) set to deliver 0.5 mA for 10 minutes using an 8 sq cm saline soaked sponge electrode. Intervention arms will be separated by at least 1 week.
Sponsors
Dr James Stinear
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
45 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
First ever ischemic or haemorrhagic stroke between 6 months and 5 years prior to enrolment; the ability to initiate gait without assistive devices such as walking sticks, handrails; a Fugl-Meyer Lower Limb score between 15 and 30 (out of 34); paretic ankle dorsiflexion of > 10 degrees; the ability to follow instructions; and the ability to give informed consent. Except for age (>45 years), there are no specific inclusion criteria for healthy subjects.
Exclusion criteria
Brainstem or cerebellar infarction; other neurological or medical disorders that would prevent participation in the study; contraindications to TMS or MRI; and medications that are known to alter motor system excitability. Healthy subjects will be excluded if they have any neurological disorders; orthopaedic conditions that might affect gait; contraindications to TMS; and medications that are known to alter motor system excitability.
Outcome results
None listed