The Effects of Heel Distraction Height on Foot Loading With Carbon Fiber Custom Dynamic Orthoses

NCT ID: NCT06127316

Last Updated: 2025-12-31

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-08-16
• Study Completion Date: 2026-06-01

Brief Summary

Carbon fiber custom dynamic orthoses (CDOs) and unloading ankle foot orthoses (AFOs) have shown varying levels of success in reducing forces acting on different regions of the bottom of the foot during gait. CDOs and unloading AFOs have shown differing offloading capabilities across different regions of the foots (hindfoot, midfoot, forefoot) which may be related to a distinct difference between CDOs and unloading AFOs: CDOs do not suspend, or distract, the foot away from the footplate. The purpose of this study is to determine the effects of CDOs and heel distraction height (the distance between the heel and the footplate) on limb loading and motion during gait as well as patient reported pain, and comfort.

Detailed Description

Carbon fiber custom dynamic orthoses (CDOs) have been used to improve function, reduce pain, and offload the foot and ankle for individuals with a number of conditions affecting the lower extremity. CDOs consist of a proximal cuff that wraps around the leg just below the knee, a posterior carbon fiber strut that bends to store and return energy during mid to late stance, a semi-rigid carbon fiber footplate, and, in some cases, a foam heel wedge placed in the shoe. Unloading ankle foot orthoses (AFOs) have also been used for a number of lower extremity conditions, including traumatic injuries, in effort to reduce forces and pressure acting under the foot. Unloading AFOs have been created using many different designs, which include a proximal cuff just below the knee, a rigid strut (made of metal, plastic, etc.), and some sort of foot component (footplate, shoe, etc.).

Both CDOs and unloading AFOs have shown varying levels of success in reducing forces acting on different regions of the bottom of the foot during gait. The differences in loading may be related to a distinct difference between CDOs and unloading AFOs: CDOs do not suspend, or distract, the foot away from the footplate.

The purpose of this study is to determine the effects of CDOs and heel distraction height (the distance between the heel and the footplate) on limb loading and motion as well as patient reported pain and comfort. In this study, forces acting under the foot will be measured using wireless Loadsol insoles (Novel GMBH, St. Paul, MN) as participants walk without an orthosis (NoCDO) and with a CDO with three different posterior strut lengths resulting in three different levels of heel distraction (0cm, 1cm, 2cm) at self-selected and controlled speeds. Additionally, gait kinematic and kinetics will be measured using infrared motion capture cameras (Vicon Motion Systems Ltd., Denver, CO) and force plates (AMTI, Watertown, MA). Participants will be provided a lift for the contralateral limb to reduce the effects of leg length discrepancies during walking. Loadpad force measuring sensors (Novel GMBH, St. Paul, MN) will be used to measure forces within the CDO proximal cuff. After walking in each condition, participants will complete questionnaires concerning pain and orthosis comfort.

Conditions

Traumatic Lower Limb Injury

Keywords

Plantar Force; Ankle Foot Orthosis; Carbon Fiber Orthosis; Biomechanics

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: OTHER
• Blinding Strategy: SINGLE

Study Groups

NoCDO

Participants will complete study activities without a CDO

Group Type: NO_INTERVENTION

No interventions assigned to this group

0cm Distraction

Participants will complete study activities while wearing a CDO with 0cm of heel distraction height

Group Type: EXPERIMENTAL

Carbon Fiber Custom Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The carbon fiber custom dynamic orthoses (CDOs) used in this study will consist of a semi-rigid carbon fiber footplate, a carbon fiber posterior strut, and a proximal cuff that wraps around the leg below the knee. The CDO will be modular in design which will allow three carbon fiber struts of the same stiffness and differing lengths to be used to implement 0cm, 1cm, and 2cm levels of heel distraction height. A longer posterior strut will move the carbon fiber footplate away from the participants foot to create the heel distraction height.

1cm Distraction

Participants will complete study activities while wearing a CDO with 1cm of heel distraction height

Group Type: EXPERIMENTAL

Carbon Fiber Custom Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The carbon fiber custom dynamic orthoses (CDOs) used in this study will consist of a semi-rigid carbon fiber footplate, a carbon fiber posterior strut, and a proximal cuff that wraps around the leg below the knee. The CDO will be modular in design which will allow three carbon fiber struts of the same stiffness and differing lengths to be used to implement 0cm, 1cm, and 2cm levels of heel distraction height. A longer posterior strut will move the carbon fiber footplate away from the participants foot to create the heel distraction height.

2cm Distraction

Participants will complete study activities while wearing a CDO with 2cm of heel distraction height

Group Type: EXPERIMENTAL

Carbon Fiber Custom Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The carbon fiber custom dynamic orthoses (CDOs) used in this study will consist of a semi-rigid carbon fiber footplate, a carbon fiber posterior strut, and a proximal cuff that wraps around the leg below the knee. The CDO will be modular in design which will allow three carbon fiber struts of the same stiffness and differing lengths to be used to implement 0cm, 1cm, and 2cm levels of heel distraction height. A longer posterior strut will move the carbon fiber footplate away from the participants foot to create the heel distraction height.

Interventions

Carbon Fiber Custom Dynamic Orthosis (CDO)

The carbon fiber custom dynamic orthoses (CDOs) used in this study will consist of a semi-rigid carbon fiber footplate, a carbon fiber posterior strut, and a proximal cuff that wraps around the leg below the knee. The CDO will be modular in design which will allow three carbon fiber struts of the same stiffness and differing lengths to be used to implement 0cm, 1cm, and 2cm levels of heel distraction height. A longer posterior strut will move the carbon fiber footplate away from the participants foot to create the heel distraction height.

Intervention Type: DEVICE

Other Intervention Names

Ankle Foot Orthosis (AFO)

Eligibility Criteria

Inclusion Criteria

1. Ages 18-65 years

2. Traumatic hindfoot injury (soft tissue injury or fracture affecting the hindfoot or ankle)

3. Mechanical pain with limb loading (>=4/10 on Numerical Pain Rating Scale)

4. Ability to walk 50 feet at a slow to moderate pace

5. Ability to walk without a cane or crutch

6. 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, etc.

3. Ankle weakness resulting from spinal cord injury or central 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. Uncorrected visual or hearing impairments

9. Require use of a knee stabilizing device to perform daily activities (i.e., Knee ankle foot orthosis, knee orthosis, etc.)

10. Pregnancy

11. Body mass index greater than 40 kg/m2

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fabtech Systems

UNKNOWN

Sponsor Role: collaborator

University of Iowa

OTHER

Sponsor Role: lead

Responsible Party

Jason Wilken

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Jason M Wilken, PT,PhD

Role: PRINCIPAL_INVESTIGATOR

University of Iowa

Locations

University of Iowa

Iowa City, Iowa, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Jason M Wilken, PT, PhD

Role: CONTACT

Phone: 3193356857

Email: jason-wilken@uiowa.edu

Kirsten M Anderson, PhD

Role: CONTACT

Phone: 3193530431

Email: kirsten-m-anderson@uiowa.edu

Facility Contacts

Jason M Wilken, PT, PhD

Role: primary

Kirsten M Anderson, PhD

Role: backup

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Other Identifiers

202302397

Identifier Type: -

Identifier Source: org_study_id