NCT05154253 · Northern Arizona University
Augmenting Ankle Plantarflexor Function in Cerebral Palsy
What this study is about
The first specific aim is to quantify improvement in ankle muscle function and functional mobility following targeted ankle resistance gait training in ambulatory children with cerebral palsy (CP).
View original scientific description
The first specific aim is to quantify improvement in ankle muscle function and functional mobility following targeted ankle resistance gait training in ambulatory children with cerebral palsy (CP). The primary hypothesis for the first aim is that targeted ankle resistance training will produce larger improvements in lower-extremity motor control, gait mechanics, and clinical measures of mobility assessed four- and twelve-weeks post intervention compared to standard physical therapy and standard gait training. The second specific aim is to determine the efficacy of adaptive ankle assistance to improve capacity and performance during sustained, high-intensity, and challenging tasks in ambulatory children with CP. The primary hypothesis for the second aim is that adaptive ankle assistance will result in significantly greater capacity and performance during the six-minute-walk-test and graded treadmill and stair stepping protocols compared to walking with ankle foot orthoses and walking with just shoes.
Interventions
DEVICE
Biomotum Spark: Robotic ankle assistance
A lightweight assistive wearable ankle robotic device.
DEVICE
Biomotum Spark: Robotic ankle resistance
A lightweight resistive wearable ankle robotic device.
OTHER
Standard gait training
Standard gait training without a device.
DEVICE
Ankle foot orthosis
Standard ankle foot orthosis
OTHER
Standard physical therapy
Physical therapy without a device.
OTHER
Standard walking
Walking without a device
Primary outcome measures
Change in preferred walking speed
Time frame: Immediately after the intervention
Participant's preferred walking speed compared after to before the intervention
Change in preferred walking speed
Time frame: 2 weeks after the intervention
Participant's preferred walking speed compared after to before the intervention
Change in preferred walking speed
Time frame: 12 weeks after the intervention
Participant's preferred walking speed compared after to before the intervention
Change in similarity of plantarflexor muscle activity
Time frame: Immediately after the intervention
Similarity of the plantarflexor muscle activity profile across the gait cycle, measured using surface electromyography (the measurement tool) of the soleus muscle, to the average unimpaired electromyography muscle activity profile, as calculated via cross-correlation coefficient. A higher value indicates greater similarity.
Change in similarity of plantarflexor muscle activity
Time frame: 2 weeks after the intervention
Similarity of the plantarflexor muscle activity profile across the gait cycle, measured using surface electromyography (the measurement tool) of the soleus muscle, to the average unimpaired electromyography muscle activity profile, as calculated via cross-correlation coefficient. A higher value indicates greater similarity.
Change in similarity of plantarflexor muscle activity
Time frame: 12 weeks after the intervention
Similarity of the plantarflexor muscle activity profile across the gait cycle, measured using surface electromyography (the measurement tool) of the soleus muscle, to the average unimpaired electromyography muscle activity profile, as calculated via cross-correlation coefficient. A higher value indicates greater similarity.
Change in 6-minute-walk-test distance
Time frame: Immediately after the intervention
Distance traveled in 6 minutes during a 6-minute-walk-test protocol. A longer distance indicates greater walking capacity.
Change in 6-minute-walk-test distance
Time frame: 2 weeks after the intervention
Distance traveled in 6 minutes during a 6-minute-walk-test protocol. A longer distance indicates greater walking capacity.
Change in 6-minute-walk-test distance
Time frame: 12 weeks after the intervention
Distance traveled in 6 minutes during a 6-minute-walk-test protocol. A longer distance indicates greater walking capacity.
Change in variance in muscle activity
Time frame: Immediately after the intervention
Variance in muscle activity accounted for by one muscle synergy assessed using surface electromyography (the measurement tool) of the soleus, tibialis anterior, medial hamstrings, and vastus medialis. Muscle synergies will be computed from non-negative matrix factorization. Lower variance accounted for by one muscle synergy indicates a desired greater complexity of motor control.
Change in variance in muscle activity
Time frame: 2 weeks after the intervention
Variance in muscle activity accounted for by one muscle synergy assessed using surface electromyography (the measurement tool) of the soleus, tibialis anterior, medial hamstrings, and vastus medialis. Muscle synergies will be computed from non-negative matrix factorization. Lower variance accounted for by one muscle synergy indicates a desired greater complexity of motor control.
Change in variance in muscle activity
Time frame: 12 weeks after the intervention
Variance in muscle activity accounted for by one muscle synergy assessed using surface electromyography (the measurement tool) of the soleus, tibialis anterior, medial hamstrings, and vastus medialis. Muscle synergies will be computed from non-negative matrix factorization. Lower variance accounted for by one muscle synergy indicates a desired greater complexity of motor control.
Change in stride length
Time frame: Immediately after the intervention
Participant stride length during walking. Longer stride length is desired.
Change in stride length
Time frame: 2 weeks after the intervention
Participant stride length during walking. Longer stride length is desired.
Change in stride length
Time frame: 12 weeks after the intervention
Participant stride length during walking. Longer stride length is desired.
Change in stride-to-stride variability stride length
Time frame: Immediately after the intervention
Stride-to-stride variability of lower-extremity muscle activity for the soleus, tibias anterior, vastus lateralis, and medial hamstrings, measured via surface electromyography and calculated as the variance ratio across strides.
Change in stride-to-stride variability stride length
Time frame: 2 weeks after the intervention
Stride-to-stride variability of lower-extremity muscle activity for the soleus, tibias anterior, vastus lateralis, and medial hamstrings, measured via surface electromyography and calculated as the variance ratio across strides.
Change in stride-to-stride variability stride length
Time frame: 12 weeks after the intervention
Stride-to-stride variability of lower-extremity muscle activity for the soleus, tibias anterior, vastus lateralis, and medial hamstrings, measured via surface electromyography and calculated as the variance ratio across strides.
Change in walking posture
Time frame: Immediately after the intervention
Peak Lower-extremity joint angles summed across the ankle, knee, and hip joints, measured using motion capture (the measurement tool).
Change in walking posture
Time frame: 2 weeks after the intervention
Peak Lower-extremity joint angles summed across the ankle, knee, and hip joints, measured using motion capture (the measurement tool).
Change in walking posture
Time frame: 12 weeks after the intervention
Peak Lower-extremity joint angles summed across the ankle, knee, and hip joints, measured using motion capture (the measurement tool).
Change in Gross Motor Function Measure-66 sec. D&E
Time frame: Immediately after the intervention
Gross Motor Function Measure - 66, sections (D) standing, and (E) walking, running and jumping. Higher scores are better, and range from 0-3 for each measure.
Change in Gross Motor Function Measure-66 sec. D&E
Time frame: 2 weeks after the intervention
Gross Motor Function Measure - 66, sections (D) standing, and (E) walking, running and jumping. Higher scores are better, and range from 0-3 for each measure.
Change in Gross Motor Function Measure-66 sec. D&E
Time frame: 12 weeks after the intervention
Gross Motor Function Measure - 66, sections (D) standing, and (E) walking, running and jumping. Higher scores are better, and range from 0-3 for each measure.
Change in plantar-flexor strength
Time frame: Immediately after the intervention
Plantar-flexor muscle strength measured via hand-held dynamometry.
Change in plantar-flexor strength
Time frame: 2 weeks after the intervention
Plantar-flexor muscle strength measured via hand-held dynamometry.
Change in plantar-flexor strength
Time frame: 12 weeks after the intervention
Plantar-flexor muscle strength measured via hand-held dynamometry.
Distance traveled
Time frame: 1 day
Distance traveled during the 6-minute-walk-test, and treadmill and stair stepper bruce protocols.
Metabolic cost of transport from indirect calorimetry
Time frame: 1 day
Metabolic cost estimated from a wearable indirect calorimetry system during the 6-minute-walk-test, and treadmill and stair stepper bruce protocols
Subject perceived exertion
Time frame: 1 day
Subject perceived exertion (validated pictorial pediatric exertion scale). The scale is from 1-10, where a higher number indicates more effort.
Average muscle activity
Time frame: 1 day
Average stance-phase plantar flexor muscle activity assessed through surface electromyography of the soleus muscle.
Heart Rate
Time frame: 1 day
Average heart rate during each testing condition measured via chest-mounted heart rate monitor.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Ages between 8 and 21 years old, inclusive. Diagnosis of CP and a pathological gait pattern caused by ankle dysfunction.
- Able to understand and follow simple directions (based on parent report, if needed) and walk at least 30 feet with or without a walking aid (Gross Motor Function Classification System (GMFCS) Level I-III).
- At least 20° of passive plantar-flexion range of motion.
Exclusion criteria
- Concurrent treatment other than those assigned during the study.
- A condition other than CP that would affect safe participation.
- Surgical intervention within 6 months of participation.
Where
- Minneapolis, Minnesota
Collaborators
Gillette Children's Specialty Healthcare, University of Washington
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Mar 3, 2026 · Source of record for eligibility and locations