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

Not Applicable

Recruiting

• Conditions: Healthy; Lower Limb Injury; Post-Traumatic Osteoarthritis
• Interventions: Device: Carbon Fiber Custom Dynamic Orthosis (CDO)

• Registration Number: NCT05456295
• Lead Sponsor: University of Iowa

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.

Study Timeline

• Study First Submitted: 2022-06-20
• Study First Submitted QC: 2022-07-08
• Study First Posted: 2022-07-13
• Study Start: 2023-05-17
• Status Verified: 2025-01
• Last Update Submitted: 2025-01-22
• Last Update Posted: 2025-01-27
• Primary Completion: 2025-09
• Study Completion: 2026-09

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 34

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.

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. Medical conditions or injuries that have limited participation in work or exercise in the last 6 months.
4. Medical conditions of injuries limiting function for greater than 6 weeks.
5. Uncorrected visual or hearing impairments.
6. Use of an assistive device.
7. Pregnancy
8. Body mass index greater than 35.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
CUFF-A	Carbon Fiber Custom Dynamic Orthosis (CDO)	The first study CDO will be designated CUFF-A
CUFF-B	Carbon Fiber Custom Dynamic Orthosis (CDO)	The first study CDO will be designated CUFF-B
CUFF-C	Carbon Fiber Custom Dynamic Orthosis (CDO)	The first study CDO will be designated CUFF-C
CUFF-D	Carbon Fiber Custom Dynamic Orthosis (CDO)	The first study CDO will be designated CUFF-D

Primary Outcome Measures

Name	Time	Method
Plantar Force Impulse (forefoot)	Baseline	Plantar 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 (total foot)	Baseline	Force data (N) collected from the total foot (100% of sensor), measured between the foot and orthosis during gait.
Plantar Force Impulse (midfoot)	Baseline	Plantar 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 (midfoot)	Baseline	Force data (N) collected from the total foot (middle 30% of sensor), measured between the foot and orthosis during gait.
PROMIS Patient Reported Outcomes for Physical Function	Baseline	The 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 Interference	Baseline	The 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.
Plantar Force Impulse (total foot)	Baseline	Plantar 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)	Baseline	Force data (N) collected from the total foot (distal 40% of sensor), measured between the foot and orthosis during gait.
Peak Plantar Force (hindfoot)	Baseline	Force data (N) collected from the total foot (proximal 30% of sensor), measured between the foot and orthosis during gait.
Numerical Pain Rating Scale	Baseline	Pain will be assessed using a standard 11-point numerical pain rating scale, in which 0 = no pain and 10 = worst pain imaginable.
Plantar Force Impulse (hindfoot)	Baseline	Plantar 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.
Participant Device Preference	Baseline	The 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.

Secondary Outcome Measures

Name	Time	Method
Modified Socket Comfort Score (Comfort)	Baseline	Comfort scores range from 0 = most uncomfortable to 10 = most comfortable.
Peak Ankle Moment	Baseline	Peak ankle moment (Nm/kg) during gait.
Ankle Range of Motion	Baseline	Peak ankle dorsiflexion (degrees) during gait.
Peak Ankle Power	Baseline	Peak ankle power (W/kg) during gait.
Modified Socket Comfort Score (Smoothness)	Baseline	Comfort scores range from 0 = least smooth to 10 = most smooth.

Trial Locations

Locations (1)

University of Iowa; 🇺🇸 Iowa City, Iowa, United States