Cerebral Palsy
Conditions
Brief summary
This study seeks to determine how an adjustable stiffness ankle braces affects walking performance and biomechanics in cerebral palsy.
Detailed description
Our first aim is to confirm that the differential and adjustable stiffness (DAS) AFO improves plantarflexor push-off power and range of motion compared to standard (physician prescribed) AFOs during walking in CP. Our second aim is to confirm that the differential and adjustable stiffness (DAS) AFO improves plantarflexor muscle activity while maintaining improved posture compared to standard AFOs during walking in CP. Our third aim is to validate the need and usability of real-time stiffness adjustment during play and school activities; obtain feedback from the children, their parents, and orthotists to design the MVP.
Interventions
DEVICEDifferential and adjustable stiffness AFO (DAS-AFO)
Walking with a differential and adjustable stiffness AFO (DAS-AFO)
Sponsors
Northern Arizona University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
8 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
* Age between 8-35 years old, inclusive * Diagnosis of cerebral palsy (CP) * Gross motor functional classification score level I, II, or III * Physician-prescribed AFOs of common design (i.e., rigid molded thermoplastic) * Ability to walk for 6 minutes on a treadmill * At least 20° of passive plantar-flexion range of motion * No concurrent treatment other than those assigned during the study * No condition other than CP that would affect safe participation * No surgery within 6 months of participation.
Exclusion criteria
-Excessive knee flexion during walking caused by CP
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Muscle Activity | day 1 | Change in integrated soleus electromyography (mV/mV) muscle activity during stance phase of walking. |
| Change in Metabolic Cost of Transport | day 1 | Change in metabolic cost of transport during walking. To calculate the metabolic cost of transport, the standing baseline metabolic rate for each participant and each trial was subtracted from their walking metabolic rate to estimate the net metabolic rate of walking. Next, we normalized the net metabolic rate of walking by each participant's body mass (m) and walking speed to calculate the metabolic cost of transport (J/kg\*m), averaged over the last two minutes of each condition. |
| Change in Ankle Power | 1 day during walking | Change in peak ankle power during stance phase measured in w/kg. Ankle kinematics and kinetics were calculated in OpenSim using the collected three-dimensional motion capture and the ground reaction forces. The joint kinematics and ground reaction forces were filtered using a low pass fourth order recursive Butterworth filter with a cut-off frequency of 6 Hz before being used to calculate joint kinetics. The ground reaction forces were collected using two force places associated with the instrumented treadmill (Bertec Corp, Columbus, USA) collected at 1200 Hz. The resultant joint kinetics were then further filtered using the same filtering parameters. Ankle joint power was calculated as the product of the joint moment and joint angular velocity. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Study Group Participants will walk with the new AFO, their own AFOs, and no AFOs.
Differential and adjustable stiffness AFO (DAS-AFO): Walking with a differential and adjustable stiffness AFO (DAS-AFO) | 11 |
| Total | 11 |
Baseline characteristics
| Characteristic | Study Group | — |
|---|---|---|
| Age, Continuous | 21.5 years STANDARD_DEVIATION 10.1 | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Region of Enrollment United States | 11 participants | — |
| Sex: Female, Male Female | 2 Participants | — |
| Sex: Female, Male Male | 9 Participants | — |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 11 |
| other Total, other adverse events | 0 / 11 |
| serious Total, serious adverse events | 0 / 11 |
Outcome results
Primary
Change in Ankle Power
Change in peak ankle power during stance phase measured in w/kg. Ankle kinematics and kinetics were calculated in OpenSim using the collected three-dimensional motion capture and the ground reaction forces. The joint kinematics and ground reaction forces were filtered using a low pass fourth order recursive Butterworth filter with a cut-off frequency of 6 Hz before being used to calculate joint kinetics. The ground reaction forces were collected using two force places associated with the instrumented treadmill (Bertec Corp, Columbus, USA) collected at 1200 Hz. The resultant joint kinetics were then further filtered using the same filtering parameters. Ankle joint power was calculated as the product of the joint moment and joint angular velocity.
Time frame: 1 day during walking
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Study Group | Change in Ankle Power | 0.01 w/kg | Standard Deviation 0.61 |
Primary
Change in Metabolic Cost of Transport
Change in metabolic cost of transport during walking. To calculate the metabolic cost of transport, the standing baseline metabolic rate for each participant and each trial was subtracted from their walking metabolic rate to estimate the net metabolic rate of walking. Next, we normalized the net metabolic rate of walking by each participant's body mass (m) and walking speed to calculate the metabolic cost of transport (J/kg\*m), averaged over the last two minutes of each condition.
Time frame: day 1
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Study Group | Change in Metabolic Cost of Transport | 0.57 J/kg*m | Standard Deviation 1.16 |
Primary
Change in Muscle Activity
Change in integrated soleus electromyography (mV/mV) muscle activity during stance phase of walking.
Time frame: day 1
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Study Group | Change in Muscle Activity | -0.09 percent change based on mV/mV measures | Standard Deviation 0.1 |