The Effects of AFO Heel Height and Stiffness on Gait

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of pregnant individuals, and resulting inability to account for its effect on resulting outcomes participants will be withdrawn from the study.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.