Ankle-foot Orthoses for Peripheral Artery Disease

The investigators will test the hypothesis that PAD patients using an AFO during a graded
exercise test will demonstrate a greater PWT compared to PWT assessed without the use of an
AFO. Secondary hypotheses include evaluation of the effect of an AFO on: 1) calf muscle
function, 2) claudication onset time, 3) functional ability, 4) peak oxygen consumption, and
5) patient-reported outcomes. We will also examine the effects of the AFO on outcomes
following 12 weeks of community walking.

Inclusion Criteria:

- Men and women diagnosed with atherosclerotic peripheral arterial disease (PAD).

- Patients who experience calf claudication

- ≥40 years of age

- An abnormal ankle-brachial index (ABI) of ≤.90.

- For patients with an ABI >.90 and <1.00, a post-exercise ABI drop of 15% or more
compared to the resting ABI

Exclusion Criteria:

- Lower extremity amputation(s) which interfere(s) with walking.

- Critical limb ischemia (i.e., ischemic rest pain, ulcers/gangrene on the lower
extremities).

- Non-atherosclerotic PAD (e.g., popliteal entrapment syndrome, Takayasu's arteritis)

- Major surgical procedures that are contraindicated to an exercise program (e.g.,
recent organ transplant) or coronary artery bypass graft within 6 months prior to
screening.

- Primarily limitations to exercise due to chronic obstructive pulmonary disease, angina
or heart failure.

- Myocardial infarction within 3 months prior to screening.

- Acute coronary syndrome symptoms diagnosed at time of screening.

- Significant ischemic changes (documented on the 12-lead electrocardiogram) with
horizontal or down-sloping ST-segment depression ≥ 0.5mm at rest and >1 mm with
exercise in 3 beats for 2 contiguous leads, relative to the PR-segment (or ST-segment
elevation ≥1mm).

- Transient ischemic attack or stroke 3 months prior to screening.

- New left bundle branch block or sustained ventricular tachycardia >30 seconds during
screening.

- Uncontrolled hypertension defined as ≥180 systolic or ≥100 diastolic resting blood
pressure during screening.

- Women who are pregnant (women of childbearing potential, a pregnancy test will be
performed at screening.

- Individuals currently incarcerated.

- Evidence of acute impairment from alcohol or other ilicit drugs.

- Lack of diabetes control (glycated hemoglobin >12%)

- Patients who are anemic (Hgb <11 g/dL for women and <10 g/dL for men).

- Any other clinically significant diseases (e.g., pulmonary, renal, psychiatric,
immunological) that are not stabilized or may otherwise confound the results of the
study.