Iterative Design of Custom Dynamic Orthoses to Reduce Articular Contact Stress

NCT ID: NCT04562896

Last Updated: 2026-01-30

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 22 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-01-08
• Study Completion Date: 2023-10-05

Brief Summary

The proposed study evaluates the effect of carbon fiber brace design on forces across the ankle joint. Research suggests that ankle arthritis develops after ankle fracture, in part, due to elevated forces on the cartilage. It is expected that carbon fiber braces can be designed to reduce forces in the ankle joint and thereby reduce the risk of developing arthritis following traumatic injury. In this study, brace geometry will be varied to determine how these changes influence the forces experienced by ankle cartilage. The proposed study will provide evidence that can be used by clinicians and researchers to design braces that most effectively reduce forces on ankle cartilage.

Detailed Description

The primary purpose of this line of research is to investigate the effects of carbon fiber custom dynamic orthosis (CDO) design on the forces and contact stress at the ankle, with the goal of reducing the development of post traumatic osteoarthritis (PTOA) in the ankle. Research suggests that ankle arthritis develops, in part, due to increased contact stresses within the ankle joint following fracture. It is expected that reducing articular contact stress at the ankle has the potential to delay or prevent the development of PTOA. CDOs have been shown to significantly improve function following extremity injury, and show promise for offloading the injured limb after severe lower extremity injuries. Therefore, the proposed effort is designed to evaluate how different CDO design factors influence offloading and therefore the reduction of forces and articular contact stress at the ankle.

Adult participants will be evaluated while wearing carbon fiber braces of varied geometry. The primary dependent measure is ankle joint contact stress. Following consent and enrollment computerized tomography (CT) images will be used to determine the geometry of the joint articular surfaces. Ankle contact stress will be calculated using discrete element analysis and biomechanical data collected in subsequent data collection.

Participants will be cast and fit for three CDOs with varied geometry. Participants will be blinded to the design variation of each device and will only know them as CDO-A, CDO-B, or CDO-C. Testing will be completed under 4 conditions: No-CDO, CDO-A, CDO-B, CDO-C, with each bracing condition (A/B/C) representing a CDO design variant. Physical performance measures will incorporate tests of agility, speed, and lower limb power to ensure that changes to device design do not negatively affect physical function. Questionnaires will be used to evaluate participants' current and desired activity level, pain with and without CDO use, satisfaction with the devices, perception of comfort and smoothness between devices, and preference between CDOs. Semi-structured interviews will be completed to fully capture the participant's perspective. Lower limb forces and motion will be assessed using a computerized motion capture system and force plates in the floor. Forces between the foot and CDO will be measured using force sensing insoles, and muscle activity data will be collected using surface electromyography. Devices will be mechanically tested, and participant demographic and anthropometric data will be recorded.

Conditions

Ankle Fractures; Post-traumatic Osteoarthritis; Osteoarthritis Ankle

Study Design

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

Study Groups

No Device

Participants will be evaluated without a CDO.

Group Type: NO_INTERVENTION

No interventions assigned to this group

CDO-A

The first design variant will be designated CDO-A

Group Type: EXPERIMENTAL

Custom Carbon Fiber Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The custom carbon fiber dynamic orthoses will consist of a semi-rigid foot plate, a posterior carbon fiber strut, and a proximal cuff below the knee.

CDO-B

The second design variant will be designated CDO-B

Group Type: EXPERIMENTAL

Custom Carbon Fiber Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The custom carbon fiber dynamic orthoses will consist of a semi-rigid foot plate, a posterior carbon fiber strut, and a proximal cuff below the knee.

CDO-C

The third design variant will be designated CDO-C

Group Type: EXPERIMENTAL

Custom Carbon Fiber Dynamic Orthosis (CDO)

Intervention Type: DEVICE

The custom carbon fiber dynamic orthoses will consist of a semi-rigid foot plate, a posterior carbon fiber strut, and a proximal cuff below the knee.

Interventions

Custom Carbon Fiber Dynamic Orthosis (CDO)

The custom carbon fiber dynamic orthoses will consist of a semi-rigid foot plate, a posterior carbon fiber strut, and a proximal cuff below the knee.

Intervention Type: DEVICE

Other Intervention Names

Ankle Foot Orthosis

Eligibility Criteria

Inclusion Criteria

• Ages: 18-65
• Sustained unilateral fracture of the tibial pilon within the preceding 5 years
• The fracture has completely healed
• Ability to walk 50 feet without use of an assistive device (cane, crutch, etc.)
• Ability to walk at a slow to moderate pace
• Shoe size between women's 8 and 13.5 or men's 6.5 and 13
• Ability to read and write in English and provide written informed consent
• Individuals with elevated contact stress according to model generated using PedCAT standing CT images (will be answered after completing visit one)

• Between the ages of 18 and 65
• Shoe size between women's 8 and 13.5 or men's 6.5 and 13
• Healthy individuals without a current complaint of lower extremity pain, spine pain, or medical or neuromusculoskeletal disorders that have limited participation in work or exercise in the last 6 months
• Full active range of motion of the bilateral lower extremities and spine
• Ability to hop without pain
• Ability to perform a full squat without pain
• Ability to read and write in English and provide written informed consent

Exclusion Criteria

• Pain > 6/10 while walking
• Increase in pain during testing of 3/10 or greater
• Neurologic, musculoskeletal (including bilateral fractures) or other condition limiting function of the contralateral extremity
• Medical or psychological condition that would preclude functional testing (ex. moderate or severe brain injury, stroke, heart disease)
• Wounds to the calf that would prevent CDO fitting
• Fractures secondary to neuropathy or severe osteopenia
• Classification as non-ambulatory
• Previous fractures near the tibial pilon on the involved limb
• Surgery on involved limb anticipated in the next 6 months
• Requirement of a knee stabilizing device (i.e. KAFO, KO…) to perform daily activities
• Visual or hearing impairments that limit walking ability or limit the ability to comply with instructions given during testing
• BMI greater than 40
• Pregnancy- Per participant self-report. Due to the expected small number of pregnant individuals and resulting inability to account for its effect on resulting outcomes, participants will be withdrawn from the study.

HEALTHY ABLE-BODIED PARTICIPANTS:

• Diagnosed moderate or severe brain injury
• Prior lower extremity injury resulting in surgery or limiting function for greater than 6 weeks
• Diagnosis of a physical or psychological condition that would preclude testing (e.g. cardiac condition, clotting disorder, pulmonary condition)
• Visual or hearing impairment that would interfere with instructions given during testing
• Require an assistive device
• Wounds to the foot or calf that would prevent CDO use
• BMI greater than 40
• Pregnancy - Per participant self-report. Due to the expected small number of pregnant individuals and resulting inability to account for its effect on resulting outcomes, participants will be withdrawn from the study

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Delaware

OTHER

Sponsor Role: collaborator

Bio-Mechanical Composites

UNKNOWN

Sponsor Role: collaborator

Fabtech Systems

UNKNOWN

Sponsor Role: collaborator

University of Iowa

OTHER

Sponsor Role: lead

Responsible Party

Jason Wilken

Director of Collaborative Research and Development, 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

Countries

United States

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Other Identifiers

CDMRP-PR172087

Identifier Type: OTHER_GRANT

Identifier Source: secondary_id

202002769

Identifier Type: -

Identifier Source: org_study_id