Development of Walk Assist Device to Improve Community Ambulation

Hypothesis/Specific Aims:

The purpose of this study is to determine the effect of training with the Stride Management Assist (SMA) device vs. Impairment based physical therapy (IPT) on descending corticospinal drive to the lower limb muscles in patients post stroke. The investigators hypothesize that long-term SMA use would strengthen the connections between the motor areas of the brain and the lower limbs. Specifically, individuals in the SMA group will show higher corticospinal excitability of the lower limb muscles compared to those in the IPT group.

This is a randomized control trial comparing task specific training with the Stride Management Assist (SMA) device verses an impairment based physical therapy (IPT) approach on functional walking ability in outpatient stroke rehabilitation. Participants between the ages of 18-80 and who are 30 days or greater post stroke will be included.

This SMA robotic device assists hip flexion and extension, for each side independently. It is controlled through software run on a tablet. The device weighs 2.8 kgs, and has 2 brushless direct current motors running on a rechargeable lithium ion battery. It comes in 3 sizes (small, medium and large). It is worn around like a belt with the motors near the hips and straps on the thighs. The SMA device allows users to increase their stride length by providing assist with the motors in flexion and extension. This device is 1) simple to use in the clinical setting; 2) easily adjustable to alter according to the requirements of each subject; and, 3) can quantify the amount of assistance required to facilitate walking patterns.

Participants post stroke 30 days or greater will be recruited from inpatient, day rehabilitation and outpatient clinics. Participants will be scheduled for 18 Sessions of outpatient physical therapy plus 3 sessions of testing. The amount of sessions provided will be dependent upon compatibility with the device and ability to tolerate the device. A participant will continue with each session of the study as deemed appropriate by research staff.

* A. Phase I. (session 0): After consenting, subjects will undergo a physical evaluation and screening exam by a licensed physical therapist. If they meet study criteria, they will be randomly placed into either the SMA group or the IPT group using a random number generator and they will be entered into the study. Once they are enrolled, baseline outcome measures will be assessed by a blinded research physical therapist.
* B. Phase II. (sessions 1-9):

  * Stride Management Assist Group: Treatment consists of 30 minutes high intensity gait training with device, 15 minutes functional mobility with device.
  * Impairment Based Physical Therapy Group: Treatment will be divided into: 15 min balance training, 15 minutes functional mobility (transfers, strength or flexibility training) and 15 min high intensity gait training
* C. Phase III. (session 10): Mid treatment assessment. Outcome measures will be assessed by a blinded research physical therapist.
* D. Phase II. (sessions 11-19):

  * Stride Management Assist Group: Treatment consists of 30 minutes high intensity gait training with device, 15 minutes functional mobility with device.
  * Impairment Based Physical Therapy Group: Treatment will be divided into: 15 min balance training, 15 minutes functional mobility (transfers, strength or flexibility training) and 15 min high intensity gait training
* E. Phase IV. (session 20): Post Testing. Outcome measures will be assessed by a blinded research physical therapist.

All testing and training sessions will be under the supervision of a licensed physical therapist. All subjects will be permitted to stop physical activity or rest at any time during the study. Adverse events will be recorded.

The investigators anticipate this study will help determine if the Stride Management Assist is a practical option to better strengthen the connections between the brain and the lower limbs. The investigators do not foresee any potential pitfalls.

Eligibility Criteria:
Inclusion Criteria:

* ≥ 30-days post stroke
* Initial gait speed of \> 0.4 m/s and \< 0.8 m/s
* Adequate cognitive function (MMSE score \>17)
* Subject is willing to be randomized to the control group or the treatment group.
* Ability to sit unsupported for 30 seconds
* Ability to walk at least 10m with maximum 1 person assist,
* Ability to follow a three-step command
* Physician approval for patient participation
* Living in the community post-stroke with ability to travel to the intervention site to participate in the outpatient program and able to perform the home exercise program in the residential facility.
* Willing to carry wireless body sensors through the period of the study and to follow-up time period, post inpatient stroke, cardiac, pulmonary, or any other lower extremity physical rehabilitation
* ≥ 90 days post major orthopedic surgery (i.e. hip, knee, and/or ankle joint replacement)
* ≥ 6 months post coronary artery bypass grafting (CABG) or cardiac valve procedure
* Able and willing to give written consent and comply with study procedures, including follow-up visits
* Cannot not be participating in any other structured outpatient or home health physical therapy program

Exclusion Criteria:

* Serious cardiac conditions (hospitalization for myocardial infarction or heart surgery within 3 months, history of congestive heart failure, documented serious and unstable cardiac arrhythmias, hypertrophic cardiomyopathy, severe aortic stenosis, angina or dyspnea at rest or during activities of daily living)
* Severe arthritis or orthopedic problems that limit passive ranges of motion (ROM) of lower extremity (knee flexion contracture of \> 10°, knee flexion ROM \< 90°, hip flexion contracture \> 25°, and ankle plantar flexion contracture \> 15
* Serious medical conditions including myocardial infarction or heart surgery within 3 months, history of congestive heart failure, documented serious and unstable cardiac arrhythmias, hypertrophic cardiomyopathy, severe aortic stenosis, angina or dyspnea at rest or during activities of daily living, Severe hypertension, severe weight bearing pain, life expectancy less than one year
* Preexisting neurological disorders such as Parkinson's disease, Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis (MS), dementia
* History of major head trauma, Lower extremity amputation, Non-healing ulcers of a lower extremity, Renal dialysis or end stage liver disease, Legal blindness or severe visual impairment, a history of significant psychiatric illness
* History of unexplained, recurring headaches, epilepsy/seizures/skull fractures or skull deficits
* Medications that lower seizure threshold
* History of concussion in last 6 months
* Subject is pregnant, nursing or planning a pregnancy
* Inability to travel 3 times per week for outpatient training programs
* Participating in another clinical trial that, according to the Principal Investigator, is likely to affect study outcome or confound results