Effects of AFO heel height and stiffness on walking

The Effects of AFO Heel Height and Stiffness on Gait

NA · University of Iowa · NCT04800484

This study tests how different heel heights and stiffness of ankle foot orthoses affect the walking of people who use them every day.

Quick facts

PhaseNA
Study typeInterventional
Enrollment40 (estimated)
Ages18 Years to 70 Years
SexAll
SponsorUniversity of Iowa (other)
Locations1 site (Iowa City, Iowa)
Trial IDNCT04800484 on ClinicalTrials.gov

What this trial studies

This study evaluates how different heel heights and stiffness of ankle foot orthoses (AFO) affect the forces and motion of the lower limb during walking in individuals who use AFOs daily. Participants will walk with their AFOs and with heel cushions of varying heights and stiffness, while their movements will be analyzed using motion capture technology and force plates. The goal is to provide evidence that helps clinicians optimize AFO configurations for improved walking function.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18-70 who use AFOs for unilateral below-knee functional deficits due to musculoskeletal injuries or diseases.

Not a fit: Patients with central nervous system disorders or significant pain while walking may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to better AFO designs that enhance walking ability and comfort for patients.

How similar studies have performed: Previous studies have suggested that heel height and stiffness impact limb loading, but this specific approach is novel and aims to provide more comprehensive data.

Eligibility criteria

Show full inclusion / exclusion criteria
GROUP 1 Patient Inclusion criteria

* Ages: 18-70
* Daily AFO use to address unilateral, below knee functional deficits that result from limb injury or musculoskeletal disease (e.g. fracture, muscle and/or nerve injury, ankle arthritis)
* Greater than 2 weeks using their current AFO
* Ability to walk 50 feet without use of an assistive device (Cane, crutch, etc.)
* Ability to walk at a slow to moderate pace
* AFO fits into traditional footwear
* Able to read and write in English and provide written informed consent

GROUP 1 Patient Exclusion criteria

* Pain \> 6/10 while walking during testing or an increase in pain during testing of \> 2/10.
* Central Nervous System disorder or disease (e.g. Stroke, Cerebral Palsy, Spinal Cord Injury, or other conditions that result in lower limb spasticity).
* Disorder or disease that affects peripheral nerve function (e.g. diabetes, Charcot Marie Tooth).
* Limited contralateral lower limb function due to injury or neurological/musculoskeletal disorder.
* Use of a hinged/articulating AFO (e.g. Plantar flexion stop, Dorsiflexion assist/stop, free motion), Charcot Restraint Orthotic Walker (CROW) boot, AFOs that restrict all motion in the ankle and foot.
* Use of an AFO that crosses the knee (Knee brace)
* Insufficient space in shoe to accommodate the tallest heel wedge and their AFO
* Visual or hearing impairments that limit walking ability or could limit the ability to comply with instructions given during testing
* Pregnancy - Per participant self-report. Due 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.
* Body Mass index \> 40.

GROUP 2 Patient Inclusion Criteria

* Ages: 18-70
* Daily AFO use to address below knee functional deficits that result from disease involving the peripheral nervous system (e.g. Charcot Marie Tooth, Multiple Sclerosis, diabetes)
* Greater than 2 weeks using their current AFO (unilateral or bilateral)
* Ability to walk 50 feet without use of an assistive device (Cane, crutch, etc.)
* AFO fits into traditional footwear
* Ability to walk at a slow to moderate pace
* Able to read and write in English and provide written informed consent

GROUP 2 Patient Exclusion Criteria

* Pain \> 6/10 while walking or an increase in pain during testing of \> 2/10
* Central Nervous System disorder or disease (e.g. Stroke, Cerebral Palsy, Spinal Cord Injury, or other conditions that result in lower limb spasticity)
* Limited function due to limb injury (e.g. fracture, muscle and/or nerve injury)
* Use of a hinged/articulating AFO (e.g. Plantar flexion stop, Dorsiflexion assist/stop, free motion), Charcot Restraint Orthotic Walker (CROW) boot, AFOs that restrict all motion in the ankle and foot.
* Use of an AFO that crosses the knee (Knee brace)
* Insufficient space in shoe to accommodate the tallest heel wedge and their AFO
* Visual or hearing impairment that limit walking ability or limit the ability to comply with instructions given during testing
* Pregnancy - Per participant self-report. Due 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
* Body Mass index \> 40.

Where this trial is running

Iowa City, Iowa

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Musculoskeletal Injury, Musculoskeletal Diseases, Peripheral Nervous System Diseases, Gait Analysis, Ankle Foot Orthosis, Biomechanics

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.