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Comparative Effect of Carbon Fiber Orthosis Cuff Design on Preference, Comfort, and Mechanics

Comparative Effect of Carbon Fiber Orthosis Cuff Design on Preference, Comfort, and Mechanics

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05456295
Acronym
AFOCUFF
Enrollment
35
Registered
2022-07-13
Start date
2023-05-17
Completion date
2025-09-29
Last updated
2026-01-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy, Lower Limb Injury, Post-Traumatic Osteoarthritis

Keywords

Gait Analysis, Ankle Foot Orthosis, Carbon Fiber, Biomechanics, Adult, Arthritis, Healthy

Brief summary

Carbon fiber custom dynamic orthoses (CDOs) consist of a proximal cuff that wraps around the leg just below the knee, a posterior carbon fiber strut that stores and returns energy during gait, and a carbon fiber foot plate that supports the foot and allows bending of the posterior strut. The proximal cuff is a primary interface between the patient and the CDO and may influence comfort, preference, limb mechanics and loading, and effective stiffness of the CDO. The important role of the proximal cuff has not been examined. The purpose of this study is to determine the effects of CDO proximal cuff design on patient reported outcomes, limb mechanics and loading, and CDO mechanical characteristics.

Detailed description

Traumatic lower limb injuries often result in poor functional outcomes with long-term negative effects. Carbon fiber custom dynamic orthoses (CDOs) can improve outcomes by reducing pain, supporting the limb, and transferring forces around the limb through the CDO. CDOs consist of a proximal cuff that wraps around the leg just below the knee, a posterior carbon fiber strut that stores and returns energy during gait, and a carbon fiber foot plate that supports the foot and allows bending of the posterior strut. The proximal cuff is a primary interface between the patient and the CDO and may influence comfort, preference, limb mechanics and loading, and effective stiffness of the CDO. Although CDOs are becoming more commonly prescribed following injury the evidence available to guide clinical practice remains limited. The important role of the proximal cuff has not been systematically examined. The purpose of this study is to determine the effects of CDO proximal cuff design on patient reported outcomes, limb mechanics and loading, and CDO mechanical characteristics. Two groups of individuals will participate: individuals with post-traumatic osteoarthritis in the ankle and healthy individuals. Testing will occur without an orthosis and while wearing orthoses with four proximal cuff designs representative of currently available devices: 1) a rigid patellar tendon bearing (PTB) clamshell cuff secured using a mechanical ratcheting system, 2) a PTB shell with a fixed pivot point secured with Velcro, 3) a rigid clamshell cuff secured with Velcro, and 4) a semi-rigid cuff with a flexible outer layer secured with Velcro.

Interventions

The carbon fiber custom dynamic orthosis will consist of a semi-rigid foot plate, a posterior carbon fiber strut, and a proximal cuff that wraps around the leg below the knee. The design of the proximal cuff will differ between CUFF-A, CUFF-B, CUFF-C, CUFF-D.

Sponsors

Fabtech Systems
CollaboratorUNKNOWN
University of Iowa
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
SINGLE (Subject)

Masking description

Participants will be blinded, to the greatest extent possible, to the different CDO designs and will only be introduced to each device as CUFF-A, CUFF-B, CUFF-C, CUFF-D.

Intervention model description

All participants will be cast and fit with CDOs with four different proximal cuff designs. CDOs will be labeled as CUFF-A, CUFF-B, CUFF-C, CUFF-D. Testing order of the proximal cuff designs will be randomized to prevent influence of study results.

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

PARTICIPANTS WITH PTOA: Inclusion Criteria: 1. Ages 18-65. 2. Diagnosis of ankle PTOA. 3. Ability to walk 50 feet at a slow to moderate pace. 4. Ability to walk without a cane or crutch. 5. Ability to read and write in English and provide written informed consent.

Exclusion criteria

1. Diagnosis with a moderate or severe brain injury. 2. Diagnosis with a physical or psychological condition that would preclude functional testing (e.g. cardiac condition, clotting disorder, pulmonary condition…). 3. Ankle weakness as a result of spinal cord injury or nervous system pathology. 4. Nerve, muscle, bone, or other condition limiting function in the contralateral extremity. 5. Rheumatoid or inflammatory arthritis. 6. Necrosis of any bones in the foot or ankle. 7. Pain of 8/10 or greater during walking. 8. Surgery on study limb anticipated in the next 6 months. 9. Uncorrected visual or hearing impairments. 10. Require use of a stabilizing device (i.e. Ankle Foot Orthosis or Knee Orthosis…) to perform daily activities. 11. Pregnancy 12. Body mass index greater than 40. HEALTHY ABLE-BODIED PARTICIPANTS: Inclusion Criteria: 1. Ages 18-65. 2. Without current complaint of lower extremity pain, spine pain, open wounds or active infection. 3. Ability to hop without pain. 4. Ability to perform a full squat without pain. 5. Ability to read and write in English and provide written informed consent.

Design outcomes

Primary

MeasureTime frameDescription
Participant Device PreferenceBaselineThe participant will rank order their preference for their standard of care device (if applicable), NoCDO, CUFF-A, CUFF-B, CUFF-C, CUFF-D on a questionnaire.
Peak Plantar Force (total foot)BaselineForce data (N) collected from the total foot (100% of sensor), measured between the foot and orthosis during gait.
Plantar Force Impulse (total foot)BaselinePlantar force impulse (Ns) across the total foot (100% of sensor) will be calculated using the integral of the force over the stance phase as participants walk in each study condition.
Peak Plantar Force (forefoot)BaselineForce data (N) collected from the total foot (distal 40% of sensor), measured between the foot and orthosis during gait.
Plantar Force Impulse (forefoot)BaselinePlantar force impulse (Ns) across the total foot (distal 40% of sensor) will be calculated using the integral of the force over the stance phase as participants walk in each study condition.
Peak Plantar Force (midfoot)BaselineForce data (N) collected from the total foot (middle 30% of sensor), measured between the foot and orthosis during gait.
Plantar Force Impulse (midfoot)BaselinePlantar force impulse (Ns) across the total foot (middle 30% of sensor) will be calculated using the integral of the force over the stance phase as participants walk in each study condition.
Peak Plantar Force (hindfoot)BaselineForce data (N) collected from the total foot (proximal 30% of sensor), measured between the foot and orthosis during gait.
Plantar Force Impulse (hindfoot)BaselinePlantar force impulse (Ns) across the total foot (proximal 30% of sensor) will be calculated using the integral of the force over the stance phase as participants walk in each study condition.
Numerical Pain Rating ScaleBaselinePain will be assessed using a standard 11-point numerical pain rating scale, in which 0 = no pain and 10 = worst pain imaginable.
PROMIS Patient Reported Outcomes for Physical FunctionBaselineThe Patient Reported Outcome Information System (PROMIS) physical function Computer Adaptive Test (CAT) is a computerized assessment measuring physical function. It is scored using a T-score in which 50 is the mean of a relevant reference population and 10 is the standard deviation (SD) of that population. In a given PROMIS domain, a T-score above 50 represents more of the measured variable than the population average.
PROMIS Patient Reported Outcomes for Pain InterferenceBaselineThe Patient Reported Outcome Information System (PROMIS) pain interference Computer Adaptive Test (CAT) is a computerized assessment measuring pain interference. It is scored using a T-score in which 50 is the mean of a relevant reference population and 10 is the standard deviation (SD) of that population. In a given PROMIS domain, a T-score above 50 represents more of the measured variable than the population average.

Secondary

MeasureTime frameDescription
Ankle Range of MotionBaselinePeak ankle dorsiflexion (degrees) during gait.
Peak Ankle MomentBaselinePeak ankle moment (Nm/kg) during gait.
Peak Ankle PowerBaselinePeak ankle power (W/kg) during gait.
Modified Socket Comfort Score (Comfort)BaselineComfort scores range from 0 = most uncomfortable to 10 = most comfortable.
Modified Socket Comfort Score (Smoothness)BaselineComfort scores range from 0 = least smooth to 10 = most smooth.

Other

MeasureTime frameDescription
Medial Gastrocnemius Muscle ActivityBaselineElectromyography (EMG, % Maximum) of the medial gastrocnemius during gait.
Center of Pressure Velocity TimingBaselineTiming of peak center of pressure velocity (percent stance) during gait.
Semi-Structured InterviewBaselineSemi-structured interviews will also be used to fully capture the patients' perspectives, experience, and opinions associated with the device options they experienced as part of the study.
Center of Pressure Velocity MagnitudeBaselineMagnitude of peak center of pressure velocity (m/s) during gait.
Tibialis Anterior Muscle ActivityBaselineElectromyography (EMG, % Maximum) of the tibialis anterior during gait.
Peroneus Longus Muscle ActivityBaselineElectromyography (EMG, % Maximum) of the peroneus longus during gait.
Soleus Muscle ActivityBaselineElectromyography (EMG, % Maximum) of the soleus during gait.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026