The Effect of AposTherapy on Knee Pain

AposTherapy is a home-based exercise program utilizing footwear that causes exercise with
normal daily activity that may significantly improve function in patients with knee pain in
general, and specifically knee osteoarthritis (OA). Capitalizing on the reported excellent
adherence and clinical benefit of Apos Therapy in patients with significant lower limb
arthritis, the investigators propose to evaluate this as a conservative treatment that may
supplant/supplement traditional pain medications and physical therapy in knee OA population.

A potential use of AposTherapy as a replacement for traditional physical therapy may yield a
less costly, more effective therapy with better adherence. Problems with traditional therapy
include poor patient adherence (patients often do not complete the sessions and have very
poor adherence (about 50-60%) to home therapy programs), added cost of travel (which may be
more than $100 per session for ambulette or access-a-ride for eligible patients), and the
lack of continuation in an ongoing exercise program, leading to relapse and need for
retreatment. Additionally, access to physical therapy is limited for many patients since
there are not enough available outpatient therapy services to meet the needs of all patients.
Finding an alternative exercise program that will increase adherence, decrease total therapy
visits, and improve patient's outcomes with decreased dependence on pain medications is a
high priority from both patient care and cost management perspectives.

AposTherapy potentially overcomes many of these issues with improving/modifying abnormal
biomechanics (therefore decreasing pain), and a home-based exercise program utilizing
footwear that causes exercise with normal activity by promoting perturbation. This
biomechanical approach may significantly reduce pain and improve function in patients with
knee OA. Capitalizing on the reported excellent adherence and clinical benefit of AposTherapy
in patients with significant knee OA, the investigators propose to evaluate the biomechanical
exercise (wearing an appropriately calibrated shoe at home for a prescribed amount of time
each day) as a conservative treatment that may supplement or supplant traditional pain
medications, interventional pain procedures and physical therapy in an at-risk urban inner
city population with knee OA.

Inclusion Criteria:

- Patients suffering from symptomatic knee OA (uni/bi lateral) for at least six months,
fulfilling the ACR clinical criteria for OA of the knee, and having radiographically
assessed OA of the knee according to the Kellgren and Lawrence scale.

- Patients with VAS pain score of ≥3cm (measured at baseline).

- Males and females between the ages of 40-75.

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- Ambulatory and active patients that can participate in a rehabilitation program that
includes daily walking

- Stable medical regimen (no recent changes to the pain medication within a month)

- Able to walk at least 50 meters and scored positive on the STEADI test

- Able to understand, read and sign the informed consent form

- English or Spanish speaking

Exclusion Criteria:

- Patients suffering from acute septic arthritis.

- Patients suffering from inflammatory joint disease such as rheumatoid arthritis.

- Patients with diagnosis of avascular necrosis of the knee.

- Patients with diagnosis of neuromuscular disease.

- Patients with more than 3 falls in the last 12 months, OR any fall with an injury in
the last 12 months.

- Patients exhibiting a lack of physical or mental ability to perform or comply with the
study procedure.

- Patients with a history of pathological osteoporotic fracture

- Patients with referred pain in the knees from back or hip joint symptoms.

- Patients with severe back pain, ≥ 4 cm in visual analogue scale (0-10) [1] or
radiating leg pain

- Patients with generalized body pain (both upper and lower extremities, such as
fibromyalgia

- No major surgery to the affected limb and contralateral limb (e.g. no joint
replacements or surgical fracture repair)

- No major cardiovascular comorbidities (able to enroll in an active exercise program)

- Patient started on lipid lowering medication in last 3 months

- Any change in blood pressure medications

- No recent physical therapy (no more recent than 6 months) on the affected limb

- No active heart disease (ischemia or heart failure admissions within 6 months) and no
active COPD (exacerbation within 6 months)

- No active malignancies on ongoing treatment

- Patient with neurological gait pattern

- Patient requiring assistive device during gait analysis.