Cortical and Biomechanical Dynamics of Ankle Robotics Training in Stroke
| Status: | Completed |
|---|---|
| Conditions: | Neurology |
| Therapuetic Areas: | Neurology |
| Healthy: | No |
| Age Range: | 21 - 85 |
| Updated: | 5/5/2014 |
| Start Date: | May 2010 |
| End Date: | March 2014 |
| Contact: | Kara Longo, MS |
| Email: | klongo@grecc.umaryland.edu |
| Phone: | (410) 605-7000 |
Reduced mobility and increased fall risk are significant long-term health problems facing
those who have persistent weakness or paralysis in their legs resulting from stroke. Recent
innovations in post-stroke therapy have applied motor learning principles to improve motor
skills through regular practice of activities using the weaker limb. Because the ankle is so
critical in providing forces for normal walking and balance function, impairments at the
affected ankle pose a major limitation to achieving optimal rehabilitation outcomes. To
address this we have developed a novel ankle robot (Anklebot) to enhance physical therapy
for improving walking and balance functions after stroke. It is a computer controlled
exercise machine that can be worn during walking or in a seated position for practice with
video games. The Anklebot controllers allow for assisting users when they cannot complete a
movement, or resisting movement, or simply recording movements and forces.
Passive movement therapy has shown promise in exciting brain to muscle connections for
recovery of walking function; however it does not appear to yield optimal results,
suggesting that active involvement in task-oriented therapy is essential. Not only is
voluntary movement important to initiate this excitation, the brain mechanisms of reward and
motivation play an important role. These mechanisms have been widely studied in both humans
and animals. Core brain networks involved in reward and motivation are designed to increase
a person's involvement with their surroundings, to focus attention and to prompt one to
approach reward and avoid punishers. These increases in involvement and the elevated
emotions that are part of it have been shown to enhance performance, memory and learning.
The primary purpose of this pilot study is to investigate responses of brain and muscle
activity in stroke patients who use the Anklebot during a 3-week / 3-session/week motor
learning based training. These responses will be compared to a 3-week delayed entry period
in which the participants will perform an at-home walking program equal in time spent to the
time they will spend on the Anklebot during the 3-week / 3x/week training. In Addition,
after the 3-week delayed entry walking program the subjects will be divided into low and
high reward-feedback groups. The low reward-feedback group will receive the Anklebot
training with only immediate feedback (they will know if they succeeded on the current trial
but they will never know their cumulative score and they will receive minimal social
interaction with research team members. While the high-reward feedback group will know their
cumulative scores, will receive controlled but abundant social interaction with the research
team and will be eligible for prizes of restaurant and movie coupons during individual
training sessions and at completion of the study. This will be done to assess the ability of
higher reward conditions to increase recovery beyond that of the Anklebot training alone.
To accomplish this subjects with chronic stroke will be divided into the high and
low-reward/feedback groups and will then play a series of videogames using the Anklebot, as
we noninvasively record brain activity using electroencephalography (EEG) and muscle
activity using electromyography (EMG). We will also monitor heart rate using
electrocardiograms (ECG). In addition to analyzing brain and muscle information before,
during, and after the Anklebot training, we will also assess walking and balance functions
immediately before and after the first and last robotic training session and ask the
subjects to fill out some standardized questionnaires.
those who have persistent weakness or paralysis in their legs resulting from stroke. Recent
innovations in post-stroke therapy have applied motor learning principles to improve motor
skills through regular practice of activities using the weaker limb. Because the ankle is so
critical in providing forces for normal walking and balance function, impairments at the
affected ankle pose a major limitation to achieving optimal rehabilitation outcomes. To
address this we have developed a novel ankle robot (Anklebot) to enhance physical therapy
for improving walking and balance functions after stroke. It is a computer controlled
exercise machine that can be worn during walking or in a seated position for practice with
video games. The Anklebot controllers allow for assisting users when they cannot complete a
movement, or resisting movement, or simply recording movements and forces.
Passive movement therapy has shown promise in exciting brain to muscle connections for
recovery of walking function; however it does not appear to yield optimal results,
suggesting that active involvement in task-oriented therapy is essential. Not only is
voluntary movement important to initiate this excitation, the brain mechanisms of reward and
motivation play an important role. These mechanisms have been widely studied in both humans
and animals. Core brain networks involved in reward and motivation are designed to increase
a person's involvement with their surroundings, to focus attention and to prompt one to
approach reward and avoid punishers. These increases in involvement and the elevated
emotions that are part of it have been shown to enhance performance, memory and learning.
The primary purpose of this pilot study is to investigate responses of brain and muscle
activity in stroke patients who use the Anklebot during a 3-week / 3-session/week motor
learning based training. These responses will be compared to a 3-week delayed entry period
in which the participants will perform an at-home walking program equal in time spent to the
time they will spend on the Anklebot during the 3-week / 3x/week training. In Addition,
after the 3-week delayed entry walking program the subjects will be divided into low and
high reward-feedback groups. The low reward-feedback group will receive the Anklebot
training with only immediate feedback (they will know if they succeeded on the current trial
but they will never know their cumulative score and they will receive minimal social
interaction with research team members. While the high-reward feedback group will know their
cumulative scores, will receive controlled but abundant social interaction with the research
team and will be eligible for prizes of restaurant and movie coupons during individual
training sessions and at completion of the study. This will be done to assess the ability of
higher reward conditions to increase recovery beyond that of the Anklebot training alone.
To accomplish this subjects with chronic stroke will be divided into the high and
low-reward/feedback groups and will then play a series of videogames using the Anklebot, as
we noninvasively record brain activity using electroencephalography (EEG) and muscle
activity using electromyography (EMG). We will also monitor heart rate using
electrocardiograms (ECG). In addition to analyzing brain and muscle information before,
during, and after the Anklebot training, we will also assess walking and balance functions
immediately before and after the first and last robotic training session and ask the
subjects to fill out some standardized questionnaires.
After informed consent is obtained, this pilot study will require at least eleven visits for
all subjects. The first visit will entail screening and eligibility tests that last about 3
hours and will occur at the VAMC (Veteran's Administration Medical Center) in the Geriatric
Assessment Clinic (GAC). The second and third visits will last approximately 3 hours at the
VAMC Human Motor Performance Laboratory and will involve collection of noninvasive EEG,
surface EMG and ECG, and practice of ankle movements by using the ankle robot to play video
games. In addition measures of gait and balance function will be assessed pre- and post- the
Anklebot training. For the next 3-weeks the subjects will take part in an at-home, monitored
(log) walking program. The next seven visits (the training program) entail further practice
of ankle movements by using the ankle robot to play video games, collection of motor control
data but not the collection of any electrophysiological data.. Visit eleven (final) is the
same as visits 2 & 3.
Visit 1: Screening evaluations include review of medical records, medical and neurologic
examinations to determine eligibility. Clinical evaluations will also include the Mini
Mental State Exam (MMSE) and the Center for Epidemiologic Study (CES-D). Clinical suspicion
or evidence on these screening instruments of dementia, depression, or other cognitive
deficits that could interfere with the study will preclude further study evaluation and
prompt referral to psychiatry or other appropriate health professional for further
evaluation. The Automated Neuropsychological Assessment Metrics (ANAM) is also administered
as a comprehensive neuropsychological tool for measuring multiple facets of
neuropsychological processes that pertain to cognitive function and motor learning. In
addition participants will be asked to walk 10 meters 3 times across a gait measuring mat at
their preferred speed while in a safety harness and accompanied (not assisted) by an
experienced research assistant. This will help determine their deficit severity for grouping
during data analysis. Finally, a standard neurological examination is conducted by medically
credentialed staff.
Visit 2 & 3 & 11: After study enrollment and medical screening, subjects will be tested with
the Anklebot while EEG, EMG, and heart rate (ECG) are recorded.
First, subjects will be fitted with a stretch-lycra cap that houses 64 recessed EEG sensors
formed from tin. The participant's skin will be lightly abraded or rubbed with the end of a
Q-tip at each sensor site to remove oil and dead epidermal tissue to establish good
conductance of the EEG signal. The skin will not be broken. Using a blunt applicator
attached to a syringe, an FDA-approved non-toxic conducting gel will then be applied through
an opening in each of the 64 recording sensors to establish continuous contact of the gel
between the skin at the recording sites and the corresponding sensors. Recording sensors
will also be positioned on the skin above and below the left eye to monitor eye movements as
well as on both ear lobes to serve as "non-brain" reference sites. A ground electrode site
will be applied in the frontal region. The eye-channel and reference sites will be lightly
abraded with a pad, rubbed with alcohol, and prepared with the conducting gel to enable
continuous connection between the scalp and the sensor surface. Also, surface EMG electrodes
will be applied to tibialis anterior, gastrocnemius, and, if needed, the peroneal muscles of
the paretic leg. Leads for ECG recording will be applied bilaterally to locations
immediately inferior to the clavicles.
Once the set-up is complete, subjects will be asked to walk 10 m over an instrumented gait
mat to record gait parameters during 3 preferred and 3 fastest walking trials. Subjects will
be asked to repeat these walking tasks while performing a concurrent cognitive task
consisting of solving and verbally reporting answers to simple arithmetic problems. They
will wear a gait belt and be attended closely by research staff as they walk and receive
seated rests as required to prevent fatigue. A second test will measure balance control by
recording 30 second trials of postural sway during quiet standing on a force plate. Three
balance conditions include eyes open, eyes closed, and eyes open while performing a
concurrent cognitive task consisting of solving and verbally reporting answers to simple
arithmetic problems. Seated rests will be provided as needed.
After baseline functional testing participants will be seated in a chair and the ankle robot
will be attached to their paretic leg by means of an orthopedic knee brace and an orthopedic
shoe. Pads and cushioning will be applied as needed for proper fitting, and the knee brace
will be mounted to the chair for stability. The leg will rest on a cushioned support with
the knee at 45 degrees and the foot free to move.
Once the set-up is completed, subjects will be asked to "play" a series of videogames by
plantar- or dorsi-flexing the paretic ankle to move a corresponding cursor on a computer
screen in order to hit slowly moving targets. The first game is about two-minutes duration
and is played without robotic assistance to assess subjects' baseline motor control and
ability. Subsequently, 6 games of about 4-minutes duration will provide differing levels of
robotic support to guide or encourage the subjects to complete the prescribed ankle
movements. The nature and amount of robotic support will be varied across the session to
promote short-term motor learning and control of the paretic ankle. Upon completion of the
performance-based training series, a repeat of the two-minute unassisted game completes the
session.` Finally, subjects will be asked to repeat the postural sway and walking tests as
before.
Visits 4-10: participants will be seated in a chair and the ankle robot will be attached to
their paretic leg by means of an orthopedic knee brace and an orthopedic shoe. Pads and
cushioning will be applied as needed for proper fitting, and the knee brace will be mounted
to the chair for stability. The leg will rest on a cushioned support with the knee at 45
degrees and the foot free to move.
Once the set-up is completed, subjects will be asked to "play" a series of videogames by
plantar- or dorsi-flexing the paretic ankle to move a corresponding cursor on a computer
screen in order to hit slowly moving targets. The first game is about two-minutes duration
and is played without robotic assistance to assess subjects' baseline motor control and
ability. Subsequently, 6 games of about 4-minutes duration will provide differing levels of
robotic support to guide or encourage the subjects to complete the prescribed ankle
movements. The nature and amount of robotic support will be varied across the session to
promote short-term motor learning and control of the paretic ankle. Upon completion of the
performance-based training series, a repeat of the two-minute unassisted game completes the
session. During these training sessions no electrophysiological data will be acquired, only
motor control data acquired by the Anklebot itself.
all subjects. The first visit will entail screening and eligibility tests that last about 3
hours and will occur at the VAMC (Veteran's Administration Medical Center) in the Geriatric
Assessment Clinic (GAC). The second and third visits will last approximately 3 hours at the
VAMC Human Motor Performance Laboratory and will involve collection of noninvasive EEG,
surface EMG and ECG, and practice of ankle movements by using the ankle robot to play video
games. In addition measures of gait and balance function will be assessed pre- and post- the
Anklebot training. For the next 3-weeks the subjects will take part in an at-home, monitored
(log) walking program. The next seven visits (the training program) entail further practice
of ankle movements by using the ankle robot to play video games, collection of motor control
data but not the collection of any electrophysiological data.. Visit eleven (final) is the
same as visits 2 & 3.
Visit 1: Screening evaluations include review of medical records, medical and neurologic
examinations to determine eligibility. Clinical evaluations will also include the Mini
Mental State Exam (MMSE) and the Center for Epidemiologic Study (CES-D). Clinical suspicion
or evidence on these screening instruments of dementia, depression, or other cognitive
deficits that could interfere with the study will preclude further study evaluation and
prompt referral to psychiatry or other appropriate health professional for further
evaluation. The Automated Neuropsychological Assessment Metrics (ANAM) is also administered
as a comprehensive neuropsychological tool for measuring multiple facets of
neuropsychological processes that pertain to cognitive function and motor learning. In
addition participants will be asked to walk 10 meters 3 times across a gait measuring mat at
their preferred speed while in a safety harness and accompanied (not assisted) by an
experienced research assistant. This will help determine their deficit severity for grouping
during data analysis. Finally, a standard neurological examination is conducted by medically
credentialed staff.
Visit 2 & 3 & 11: After study enrollment and medical screening, subjects will be tested with
the Anklebot while EEG, EMG, and heart rate (ECG) are recorded.
First, subjects will be fitted with a stretch-lycra cap that houses 64 recessed EEG sensors
formed from tin. The participant's skin will be lightly abraded or rubbed with the end of a
Q-tip at each sensor site to remove oil and dead epidermal tissue to establish good
conductance of the EEG signal. The skin will not be broken. Using a blunt applicator
attached to a syringe, an FDA-approved non-toxic conducting gel will then be applied through
an opening in each of the 64 recording sensors to establish continuous contact of the gel
between the skin at the recording sites and the corresponding sensors. Recording sensors
will also be positioned on the skin above and below the left eye to monitor eye movements as
well as on both ear lobes to serve as "non-brain" reference sites. A ground electrode site
will be applied in the frontal region. The eye-channel and reference sites will be lightly
abraded with a pad, rubbed with alcohol, and prepared with the conducting gel to enable
continuous connection between the scalp and the sensor surface. Also, surface EMG electrodes
will be applied to tibialis anterior, gastrocnemius, and, if needed, the peroneal muscles of
the paretic leg. Leads for ECG recording will be applied bilaterally to locations
immediately inferior to the clavicles.
Once the set-up is complete, subjects will be asked to walk 10 m over an instrumented gait
mat to record gait parameters during 3 preferred and 3 fastest walking trials. Subjects will
be asked to repeat these walking tasks while performing a concurrent cognitive task
consisting of solving and verbally reporting answers to simple arithmetic problems. They
will wear a gait belt and be attended closely by research staff as they walk and receive
seated rests as required to prevent fatigue. A second test will measure balance control by
recording 30 second trials of postural sway during quiet standing on a force plate. Three
balance conditions include eyes open, eyes closed, and eyes open while performing a
concurrent cognitive task consisting of solving and verbally reporting answers to simple
arithmetic problems. Seated rests will be provided as needed.
After baseline functional testing participants will be seated in a chair and the ankle robot
will be attached to their paretic leg by means of an orthopedic knee brace and an orthopedic
shoe. Pads and cushioning will be applied as needed for proper fitting, and the knee brace
will be mounted to the chair for stability. The leg will rest on a cushioned support with
the knee at 45 degrees and the foot free to move.
Once the set-up is completed, subjects will be asked to "play" a series of videogames by
plantar- or dorsi-flexing the paretic ankle to move a corresponding cursor on a computer
screen in order to hit slowly moving targets. The first game is about two-minutes duration
and is played without robotic assistance to assess subjects' baseline motor control and
ability. Subsequently, 6 games of about 4-minutes duration will provide differing levels of
robotic support to guide or encourage the subjects to complete the prescribed ankle
movements. The nature and amount of robotic support will be varied across the session to
promote short-term motor learning and control of the paretic ankle. Upon completion of the
performance-based training series, a repeat of the two-minute unassisted game completes the
session.` Finally, subjects will be asked to repeat the postural sway and walking tests as
before.
Visits 4-10: participants will be seated in a chair and the ankle robot will be attached to
their paretic leg by means of an orthopedic knee brace and an orthopedic shoe. Pads and
cushioning will be applied as needed for proper fitting, and the knee brace will be mounted
to the chair for stability. The leg will rest on a cushioned support with the knee at 45
degrees and the foot free to move.
Once the set-up is completed, subjects will be asked to "play" a series of videogames by
plantar- or dorsi-flexing the paretic ankle to move a corresponding cursor on a computer
screen in order to hit slowly moving targets. The first game is about two-minutes duration
and is played without robotic assistance to assess subjects' baseline motor control and
ability. Subsequently, 6 games of about 4-minutes duration will provide differing levels of
robotic support to guide or encourage the subjects to complete the prescribed ankle
movements. The nature and amount of robotic support will be varied across the session to
promote short-term motor learning and control of the paretic ankle. Upon completion of the
performance-based training series, a repeat of the two-minute unassisted game completes the
session. During these training sessions no electrophysiological data will be acquired, only
motor control data acquired by the Anklebot itself.
Inclusion Criteria:
- Ischemic or hemorrhagic stroke greater than 3 months prior
- Residual hemiparetic gait with observable asymmetry in the gait pattern.
- Women or men aged 21 to 85 years
- Completed all conventional physical therapy.
- Adequate language and neurocognitive function to participate in training, testing,
and to give informed consent.
- Minimal ankle flexion in either direction (dorsi- or plantar-)
Exclusion Criteria:
- MMSE score < 23 (9th grade education or more) or MMSE score < 17 (8th grade education
or less)
- CES-D score > 16
- Clinical history of orthopedic, chronic pain or severe neuromuscular disorders
restricting participation in a short term ankle movement training paradigm.
- Severe or global receptive aphasia which confounds reliable testing and training.
- Women of child-bearing potential, if there is any self-reported chance that they may
be pregnant.
We found this trial at
1
site
Click here to add this to my saved trials
