Study withdrawn due to logistical and safety concerns relating to Covid-19.

Researchers at the University of Maryland Rehabilitation and Orthopaedic Institute are looking for individuals who have suffered a stroke and have leg and ankle weakness (foot-drop), to participate in a pilot study to examine the safety and effectiveness of an ankle robot walking program on walking function

This is the first in human test of walking training over-ground using a wearable, lightweight, battery operated ankle robot exoskeleton; with assistance by trained research personnel for safety. This exercise device is aimed at assisting the foot during walking to reduce foot drop and improve walking safety in chronic, mild to moderately impaired stroke survivors who have foot drop.

Possible risks of participating in this study are described in this document. The greatest risks include the risk of falling, muscle soreness, skin irritation, or cardiovascular complications. Before starting, you will have a medical history and medical assessments performed to determine if this study is safe for you. All sessions will be assisted by trained research personnel under supervision of a physical therapist, with medical personnel locally on call.

This study is designed to see if the ankle robot is safe and effective to use in restoring gait function in individuals with foot drop.

This research project will be conducted at the University of Maryland Rehabilitation and Orthopaedic Institute (UM Rehab). There will be approximately 10 individuals from the Baltimore, Maryland area recruited to voluntarily participate in this study.

If you take part in this research, you will be asked:

• To participate in this study for approximately 10 weeks total.
• Attend at least 6 ankle robot gait training sessions that will last 45-60 minutes each session, 3 times a week for 2 weeks at UM Rehab.
• Undergo a medical and neurological evaluation at screening.
• Perform balance and walking tests with and without your usual assistive walking device.
• Walk on a treadmill with the ankle robot on your foot.
• Report to the research team any changes to assistive walking device usage between training sessions, and any health-related issues or changes.
• Maintain your current medications at their current doses and schedules throughout this study, or inform the study physician about any medication changes.
• Not to participate in any other study that would affect our results.
• You will be seated and fitted with the ankle robot before each testing visit and each gait training session. During the fitting process, the ankle robot will be secured to the stroke affected lower leg using a modified shin guard that has Velcro straps. Regular shoes will be worn. The "shoe covered" affected foot will be inserted into a modified slipper. Comfort and fit will be noted. Should you have any discomfort or feeling like the ankle robot device is rubbing on skin, padding will be applied to protect the skin.
• A gait belt will be worn around the waist and research staff will use this belt to provide support, and to protect against falls during the balance/walking tests and during ankle robot gait training sessions.
• Gait training sessions will be conducted with usual assistive devices for balance and with the ankle robot turned on and turned off.
• The research team will periodically collect heart rate and blood pressure measurements to determine how hard you are working during various tasks. You will be asked how you feel while performing these tasks. Researchers will use this information to guide the gait training program.

Tests will be completed at 3 points: baseline (before beginning training), after the 2-week gait training program, and then 6 weeks after the program.

• 3 tests of balance, mobility and gait.
• Timed walking tests (10 meter and 6-minute walks) to determine functional capacity with and without assistive walking devices, and with the ankle robot both turned on and turned off.
• Walking on a treadmill (wearing a safety harness) to assess walking patterns while wearing the ankle robot both turned on and turned off.
• Walking stability tests while wearing the ankle robot device both turned on and turned off. Usual assistive walking devices (cane or walker) will be used, if necessary. The testing tasks will be performed with and without your ankle foot orthosis, if one is worn.

In some instances, if sessions are canceled due to personal or other uncontrollable factors, time in the study may exceed 10 weeks. We do not expect time commitments to exceed 14 weeks.

If there are medical or other reasons that require time away from the study for more than one month, baseline tests will be repeated, and training will resume starting at session #1.

The investigator will ask if data can be collected from your routine medical care. If agreed upon, this data will be handled the same as research data.

If granted permission, we will photograph/videotape training sessions and test visits, to provide feedback on progress during the study.

There is an option to allow these photographs/recordings to be kept by the research team for use in future presentations (slideshows, conferences, etc.) and to educate others about this research study.

POTENTIAL RISKS/DISCOMFORTS:

This study exposes you to several risks:

• Skin irritation: There is a risk that wearing the ankle robot may cause skin irritation with repeated ankle movements. The research team will check skin before and after each training session for signs of skin redness or irritation. Foam padding will be used to provide protection to skin if needed. The padding will be adjusted if any discomfort develops during any training visits or testing sessions.
• Fall risk: Falls could occur during the gait training, balance or walking tests. We will reduce the likelihood of falling by having 2 research team members present at all sessions. One team member (spotter) will walk behind you providing support by holding onto the gait belt worn around the waist. The other team member will assist the spotter and will monitor the room for potential trip hazards. A safety harness will be worn to protect against falls during walking tests performed on the treadmill.
• Muscle discomfort: Muscle soreness may be experienced. This risk is greatest during the early stages of this study before familiarization with the study-related activities. We will monitor muscle soreness during and between sessions. We will address muscle soreness by adjusting training by providing more frequent or longer rest breaks. Muscle soreness will also be addressed by applying ice to sore muscles and teaching appropriate stretching exercises.
• Joint pain: There is a very slight risk that the robot could move the foot in the wrong direction, causing joint discomfort. This is extremely unlikely, as maximal force outputs by the robot are not sufficient to cause injury to a muscle, tendon, or ligament. Further protection is provided by fail-safe switches that quickly turn the robot off in 2 milliseconds. An engineer technician will perform service checks (calibration and operational) to the robot device before and after each session. We will address joint soreness by adjusting training by providing more frequent or longer rest breaks. Joint soreness will also be addressed by applying ice to sore regions.
• Cardiac risks: This ankle robot training program is considered low intensity exercise. Exercise training can be associated with the risk of cardiovascular complications such as chest pain, heart attack, or sudden death and complications related to stress and strains of muscles, twisted ankles, or falls. This risk is increased in people who have heart disease, poor circulation to the legs, or stroke. The risk of heart attack in these people is one in 300,000 hours of exercise, and risk of death is one in 800,000 hours of exercise.
• To minimize this risk, you will first undergo a medical evaluation. All walking training sessions will be supervised by personnel trained in cardiopulmonary resuscitation (CPR), and a clinical provider will be on call. Heart rate and blood pressure will be assessed by trained study team members before and after each training session or more frequently, if indicated.
• If blood pressure or heart rate go too high or an irregular heart rate, chest pain, or leg cramps develop, the training session will be stopped immediately. An AED (automatic external defibrillator) is available on site. A "rapid response" medical team will be contacted if a medical emergency occurs during a session. This team will evaluate a participant's condition and determine if they should be transported to the nearest hospital. Heart rate and blood pressure will be periodically monitored during each session. Instructions about warning signs of cardiac events will be given (for example: chest pain, shortness of breath, lightheadedness, and pain in the arms) and reminded about these symptoms during the study.
• Privacy and confidentiality: Research staff will collect personal information during this study. This information will be protected, however, we cannot be assured of absolute privacy. This data will be kept locked in the Rehabilitation Research Center at the University of Maryland Rehabilitation and Orthopaedic Institute (UM Rehab). Personal data (name, address, and other identifiers) will remain strictly confidential. Data will be coded to protect privacy. This coded data will be used in scientific publications and presentations, and will not be personally identified. The risk of loss confidentiality will be minimized by storing data, photos, and any recorded imaging in a secure location in a locked office within a locked cabinet, with access restricted to research staff.
• Unknown risks: In addition to the risks described in this form, there may be unknown mild risks/discomforts involved in participating in this study. The research staff will update you on any new information that may affect health, welfare, or decision to stay in the study.

POTENTIAL BENEFITS

There is no guarantee that a direct benefit from participation in this study will be received. Participation may help in the development of new robotic therapies for persons with foot drop, and to learn more about how to identify those who can successfully use this robotic approach to address their foot drop.

ALTERNATIVES TO PARTICIPATION

Participation is voluntary, and the alternative is not to participate. Conventional therapy may be an alternative to taking part in this study.

COSTS TO PARTICIPANTS

There will be no uncovered research-related costs. If you are injured because of study participation, you will receive emergency medical care if needed, and assistance in getting other medical care as needed. You or your carrier will be billed for the cost of care, just as you would be billed for any other medical care. It is not the University's policy to pay compensation to research subjects for injuries resulting from a study. The study staff can give more information about this if there is a study injury. Legal compensation for any injury that may occur during the study as a result of an error by a member of the research staff or by the sponsor may be sought.

RIGHT TO WITHDRAW

Participation in this study is voluntary. You are free to withdraw their consent at any time. Refusal to take part or to stop taking part in the study will involve no penalty or loss of benefits to which they are otherwise entitled. There are no other adverse consequences (physical, social, economic, legal, or psychological), if choosing to withdraw from the research.

REMOVAL FROM RESEARCH

The investigator or sponsor can decide to withdraw you from the study at any time without your approval. Removal from the study can be for reasons related solely to you, for example, not following study-related directions to related to research participation, a new treatment becomes available for foot drop, or a new medical illness occurs. Also, the research study may be stopped by the sponsor, the Investigator, or the Institutional Review Board. The research staff will discuss all details of a study withdrawal or the study closure with participants. Questions can be asked, should this happen. The sponsor may also decide to stop the Investigator's participation in the study. In that case, participation will end unless another investigator is identified and approved by the sponsor and the Institutional Review Board. Any significant new findings which develop during the study which may affect your willingness to participate in the study will be given.

Inclusion Criteria:

• Age 21-75 years
• Greater than 3 months post stroke
• Hemiparetic stroke with foot drop (Dorsiflexion deficit)
• Dorsiflexion deficit for active range of motion (unable to reach zero degrees)
• Dorsiflexion deficit for strength with a manual motor score between 1/5 and 4/5
• Mild-moderate severity hemiparetic gait, identified by reduced stance, or reduced stance plus increased swing on affected side
• Able to participate in physical therapy for mobility recovery, defined by capacity to walk 10-m over-ground, albeit with minimal assist (FIM Mobility Subscale 4; subject can perform 75% of the task), supervision (FIM Mobility Score 5) or modified independence (FIM Mobility Score 6; use an assistive device)
• Adequate language and cognitive function to participate in routine mobility physical therapy

Exclusion Criteria:

• Cardiac history of unstable angina, recent (<3 mos.) myocardial infarction, congestive heart failure, significant valvular dysfunction
• Hypertension contraindicating rehabilitation (>160/100, two assessments)
• Peripheral arterial occlusive disease (Fontaine II)
• Orthopedic/chronic pain conditions precluding robot use
• Pulmonary or renal failure or active cancer
• Non-stroke neuromuscular or neurological conditions that restrict gait or could confound interpretation of key outcomes
• Aphasia, unable to follow 2 step commands, or communicate pain, discomfort, or sufficiently interact with PT/staff to participate in PT or PTR treatment assignments, as per judgment of a credentialed clinician
• Cognitive dysfunction that confounds participation, including diagnosis of dementia including Alzheimer's Disease and Alzheimer's Related Disorders, or active delirium (as defined by Diagnostic and Statistical Manual of Mental Disorders (DSM- 5));
• Modified Ashworth Spasticity >3 (considerable increase in muscle tone, passive movement difficult) or contractures that preclude adequate volitional range of motion (ROM) for motor learning
• Foot and lower leg pain or deformities that complicate safe and effective robot fit
• Active deep venous thrombosis
• Skin lesions, infections, other cutaneous or musculoskeletal conditions of the shank that would complicate robot attachment to the leg
• Untreated and active major depression

All IPD that underlie results in a publication will be shared.

Data will become available immediately following any and all publications arising from the study.

Publications can be accessed through journal websites and conference proceedings. This information will be made available to researchers and, more broadly, members of the public.