Robot-Assisted Physical Therapy for Foot Drop After Stroke

Overseen By Josh Rudnicki

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: NextStep Robotics Inc.

Disqualifiers: Unstable angina, Recent myocardial infarction, Congestive heart failure, Hypertension, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 20

Duration: 9 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new method to help people with foot drop after a stroke. It compares traditional physical therapy with therapy using a robot to assist movement (Ankle Robotics, also known as Ankle Exoskeleton, Anklebot, or AMBLE). The goal is to determine which method better improves walking and ankle movement. Suitable participants have ongoing foot drop issues from a stroke that occurred more than six weeks ago, affecting their walking. As an unphased trial, this study provides a unique opportunity to explore innovative therapies that might enhance recovery and improve quality of life.

Do I need to stop my current medications for the trial?

The trial protocol does not specify whether you need to stop taking your current medications.

What prior data suggests that this robot-assisted physical therapy is safe for stroke patients with foot drop?

Studies have shown that ankle robots in physical therapy for stroke patients can improve movement and strength. In one study, patients moved their ankles better after just three weeks of using a robotic device. Another study found that these robots can help people regain a steady walking pattern, often affected by foot drop after a stroke.

Patients generally tolerate ankle robots well, with no major reports of serious side effects. This suggests the technology is safe for use in physical therapy. However, as with any new treatment, monitoring for any discomfort or problems during use is important.

Overall, research supports the safety of ankle robots in helping stroke patients with foot drop. They may offer a promising option for those looking to improve their walking abilities. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the robot-assisted physical therapy for foot drop after stroke because it combines advanced robotics with traditional physical therapy to enhance recovery. Unlike standard treatments, which primarily rely on therapist-guided exercises, this approach uses an ankle robot to tailor the assistance to each individual's needs, providing precise support during challenging mobility tasks. This innovative method aims to improve gait deficits and postural transitions more effectively by adapting to the patient's progress over time, potentially leading to faster and more significant improvements in mobility.

What evidence suggests that robot-assisted physical therapy is effective for foot drop after stroke?

Research has shown that robot-assisted therapy can help treat foot drop, a condition where lifting the front part of the foot is difficult. In this trial, participants in the PTR arm will receive physical therapy while wearing an ankle robot. Studies have found that these robots can improve walking by aiding balance and foot placement. A review of research found that these devices enhance ankle movement and strength, crucial for better walking after a stroke. Another study demonstrated that wearable ankle robots can correct walking issues and increase walking speed in individuals with foot drop. These findings suggest that ankle robots could be a promising tool for improving mobility after a stroke. ^{1 3 4 6 7}

Who Is on the Research Team?

Brad Hennessie, MHA, MBA

Principal Investigator

NextStep Robotics Inc.

Are You a Good Fit for This Trial?

This trial is for adults over 18 who have had a stroke and are experiencing foot drop due to weakness or paralysis on one side of their body. They must be in the subacute phase (6 weeks to 6 months post-stroke) or chronic phase (over 6 months post-stroke). People with other conditions affecting walking, severe hypertension, recent serious illness, significant heart issues, or cognitive impairments that prevent following instructions cannot participate.

Inclusion Criteria

I am in the recovery phase of a stroke, with weakness in my leg causing foot-drop.

I have a noticeable limp due to weakness on one side.

Exclusion Criteria

I have not been hospitalized for a severe condition in the last 3 months.

My blood pressure is too high for physical therapy (over 160/100 twice).

You have trouble speaking or understanding and following simple instructions.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive 18 sessions of robot-assisted physical therapy (PTR) or physical therapy (PT) alone over 9 weeks to improve foot drop outcomes.

9 weeks

18 sessions (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment, with assessments at 9 and 21 weeks.

12 weeks

2 visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Ankle Robotics

Trial Overview The study compares robot-assisted physical therapy (PTR) with standard physical therapy alone for treating foot drop after a stroke. Over nine weeks and eighteen sessions, it measures improvements in gait biomechanics and muscle strength through both observation and clinician assessments.

How Is the Trial Designed?

Group I: X-PTR, Cross over group for Physical Therapy n Sub-Acute group. Experimental Treatment 1 Intervention

Participants enrolled in the physical therapy only group will be given the option to re-enroll as a cross over participant to receive 18 one-hour PT training sessions over 9 weeks while wearing the robot initially parameterized to individual deficit severity. Subjects perform over-ground mobility tasks of increasing challenge with robotic assist, as needed. Training is generally divided into 3 phases based on individual ability to address gait deficits, postural transitions, physical demand and environmental terrain.

Group II: PTR (Physical Therapy while wearing Robot group) (Phase II) Experimental Treatment 1 Intervention

Subjects receive 18 one-hour PT training sessions over 9 weeks while wearing the robot initially parameterized to individual deficit severity. Subjects perform over-ground mobility tasks of increasing challenge with robotic assist, as needed. Training is generally divided into 3 phases based on individual ability to address gait deficits, postural transitions, physical demand and environmental terrain.

Group III: C-PTR, Chronic Stroke Subjects to receive robotic gait training therapy. Experimental Treatment 1 Intervention

Chronic stroke subjects receive 18 one-hour PT training sessions over 9 weeks while wearing the robot initially parameterized to individual deficit severity. Subjects perform over-ground mobility tasks of increasing challenge with robotic assist, as needed. Training is generally divided into 3 phases based on individual ability to address gait deficits, postural transitions, physical demand and environmental terrain.

Group IV: PT (Physical Therapy Only) (Phase II) Active Control 1 Intervention

Subjects receive 18 one-hour PT training sessions over 9 weeks. Subjects perform over-ground mobility tasks of increasing challenge with therapist assist, as needed. Training is generally divided into 3 phases based on individual ability to address gait deficits, postural transitions, physical demand and environmental terrain.

Ankle Robotics is already approved in United States, European Union, China for the following indications:

Approved in United States as Ankle Robotics for:

• Stroke rehabilitation
• Foot drop

Approved in European Union as Ankle Exoskeleton for:

• Post-stroke gait rehabilitation
• Ankle dysfunction

Approved in China as Anklebot for:

• Stroke survivors with foot drop
• Gait training

Who Is Running the Clinical Trial?

NextStep Robotics Inc.

Lead Sponsor

Trials

2

Recruited

140+

Published Research Related to This Trial

A study involving 18 stroke survivors with severe hemiplegia demonstrated that early in-bed rehabilitation using a wearable ankle robot significantly improved motor function, strength, and range of motion compared to a control group receiving standard passive movement.

The robot-guided training, which included real-time feedback and active movement exercises, led to earlier recovery of ankle movements, highlighting its potential as an effective intervention for enhancing rehabilitation outcomes in acute stroke patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Intensive In-Bed Sensorimotor Rehabilitation of Early Subacute Stroke Survivors With Severe Hemiplegia Using a Wearable Robot. Zhang, C., Huang, MZ., Kehs, GJ., et al.[2023]

Powered robotic exoskeletons are a safe intervention for gait rehabilitation in stroke patients, showing meaningful improvements in walking outcomes, especially in those who are in the sub-acute phase of recovery.

While exoskeleton training is equivalent to traditional therapy for chronic stroke patients, sub-acute patients may benefit more from this technology, indicating a need for further rigorous trials to establish its clinical effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Powered robotic exoskeletons in post-stroke rehabilitation of gait: a scoping review. Louie, DR., Eng, JJ.[2023]

In a study of 24 stroke survivors, those who underwent 6 weeks of training with a portable rehabilitation robot showed significantly greater improvements in spasticity, mobility, balance, and strength compared to those who followed a home exercise program.

Both groups experienced some improvements in mobility and strength, but the robot-assisted training was more effective in enhancing overall motor function and mobility after stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of robot-guided passive stretching and active movement training of ankle and mobility impairments in stroke. Waldman, G., Yang, CY., Ren, Y., et al.[2016]

A wearable ankle robotic device was tested on 10 acute stroke survivors over 12 sessions, showing that early in-bed rehabilitation can enhance motor control and promote neuroplasticity.

The device offers both passive stretching and active movement training, using real-time feedback to guide patients, which is crucial for effective motor recovery shortly after a stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Developing a Wearable Ankle Rehabilitation Robotic Device for in-Bed Acute Stroke Rehabilitation. Ren, Y., Wu, YN., Yang, CY., et al.[2019]

In a study involving sub-acute stroke survivors, integrating robot-assisted gait training with conventional training significantly improved gait recovery, with the swing-controlled ankle robot (SCAR) leading to a higher percentage of independent walkers (56%) compared to conventional training alone (29%).

The power-assisted ankle robot (PAAR) was found to enhance walking speed more effectively than SCAR, indicating that active powered assistance can help users walk faster and more efficiently with their affected leg during rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of wearable ankle robotics for stair and over-ground training on sub-acute stroke: a randomized controlled trial. Yeung, LF., Lau, CCY., Lai, CWK., et al.[2021]

In a 6-week study involving 8 participants with chronic stroke, robot-assisted ankle training significantly reduced passive ankle stiffness (PAS) in both dorsiflexion and plantar flexion, bringing it in line with age-matched controls.

The reduction in plantar flexion PAS was strongly correlated with improvements in paretic step and stride lengths during walking, indicating that this training method positively impacts gait function in stroke survivors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Changes in passive ankle stiffness and its effects on gait function in people with chronic stroke. Roy, A., Forrester, LW., Macko, RF., et al.[2019]

A single session of training with an impedance-controlled ankle robot (anklebot) significantly improved motor control in the paretic ankle of chronic stroke patients, showing increased targeting accuracy, higher angular speeds, and smoother movements after just one hour of training.

The improvements in motor control metrics were maintained 48 hours after training, suggesting that the anklebot may facilitate short-term motor learning and adaptation in stroke rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short-term ankle motor performance with ankle robotics training in chronic hemiparetic stroke. Roy, A., Forrester, LW., Macko, RF.[2019]

Wearable robotic exoskeletons (REs) significantly improve gait and balance in adults with acquired brain injury (ABI), enhancing parameters like step length, walking speed, and spatial symmetry.

The study indicates that high-dose, repetitive gait training with REs can effectively promote functional recovery in individuals with ABI, as evidenced by improved center of pressure displacement and reduced gait cycle time.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Changes in Center of Pressure after Robotic Exoskeleton Gait Training in Adults with Acquired Brain Injury. Karunakaran, KK., Pamula, S., Nolan, KJ.[2021]

Wearable ankle robots show promise in improving gait rehabilitation for stroke survivors, with 97 participants demonstrating enhanced peak dorsiflexion, propulsion on the affected side, and increased walking speed after training.

The study highlights the effectiveness of mixed sensing technology in detecting motion intention, but emphasizes the need for more comparative trials and multicenter randomized controlled trials to further validate the clinical benefits of these devices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Wearable Ankle Robots in Post-stroke Rehabilitation of Gait: A Systematic Review. Shi, B., Chen, X., Yue, Z., et al.[2020]

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT04594837

Study Details | NCT04594837 | Ankle Robotics After Stroke If wearing the AMBLE robot during physical therapy in this time-frame reduces foot drop and improves longer term outcomes measured 3 months after all robotics ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3636117/

Effectiveness of robot-assisted therapy on ankle rehabilitation The aim of this study was to provide a systematic review of studies that investigated the effectiveness of robot-assisted therapy on ankle motor and ...

3. jneuroengrehab.biomedcentral.com jneuroengrehab.biomedcentral.com/articles/10.1186/s12984-025-01624-w

A wearable ankle-assisted robot for improving gait function ... The capacity to restore steady gait after a step modification is reduced in people with poststroke foot drop using an ankle-foot orthosis.

4. frontiersin.org frontiersin.org/journals/neurorobotics/articles/10.3389/fnbot.2019.00063/full

Wearable Ankle Robots in Post-stroke Rehabilitation of Gait The aim of this study is to provide a systematic review of wearable ankle robots, focusing on the overview, classification and comparison of actuators.

5. dl.acm.org dl.acm.org/doi/10.1145/3703847.3703881

Effects of a hybrid ankle exoskeleton on foot drop ... Our study demonstrated the feasibility and advantages of the HAE for correcting gait deficits in patients with foot drop.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10789316/

Ankle rehabilitation robot training for stroke patients with ... RESULTS: After 3 weeks of treatment, all groups showed an improvement in passive and active ankle dorsiflexion range of motion (PROM and AROM) and Fugl- ...

7. mdpi.com mdpi.com/2075-1702/13/5/429

Advancements in State-of-the-Art Ankle Rehabilitation ... For treating drop foot, a 3-DOF ankle robot named AnkleBot was designed by researchers at MIT. It was actuated by brushless DC motors and provided motion while ...