Overview

Knee osteoarthritis (OA) affects an estimated 654 million people over age 40 world-wide. In the United States, approximately 16% of adults over the age of 40 have knee OA. Pain, activity limitations and disability are common symptoms. Exercise is widely recommended as a non-invasive, first line strategy for people with knee OA. Yet, less than 1/3 of adults with knee OA meet recommended levels of physical activity, and rates are even lower among people who are overweight. Furthermore, adherence to evidence-based structured programs is poor once the therapeutic support is removed. End stage disease is treated by total joint replacement. Under-active people with knee OA would benefit from general walking activity, even if joint replacement surgery is expected; however, walking is difficult and motivation is low. Thus, people with knee OA encounter a difficult paradox: exercise could help decrease pain and improve function but doing so can be difficult and may not always be possible. There is a tremendous need to address this situation. This is a small device-feasibility study evaluating the Dephy ExoBoot, a wearable powered exoskeleton, in individuals with knee OA. The study assesses whether the device can reliably deliver positive assistance during walking and is tolerated across walking tasks. Additional measures, including changes in knee loading and walking speed with versus without the device, are also collected.

Eligibility

Inclusion Criteria:

• Any gender
• 21+ years of age
• Doctor-diagnosed tibiofemoral knee osteoarthritis
• Self-report knee pain or stiffness on most days of the past month
• Self-report of difficulty walking due to at least one knee
• Self-report of restricted walking behavior (not engaging in 150 minutes of moderate walking a week) due to at least in part one knee
• Able to walk one block without the use of an assistive device (e.g. a cane or walker)
• Able to engage in a walking activity program with the wearable intervention for approximately 30 minutes using standing or sitting rests as needed

Exclusion Criteria:

• Unable to walk at least 10 minutes in the community due to an existing cardiovascular, cardiopulmonary, musculoskeletal, or neurological condition
• Planning knee, hip, ankle or back surgery within the next 6-months
• Ankle or hip osteoarthritis
• Inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis, scleroderma, Lymes Disease, Lupus)
• Bilateral total knee replacements
• Use of an assistive device (e.g., walker or cane) in home or in the community
• Self-reported fall within the past 6-months that resulted in limitations in daily activities
• Lower extremity/foot peripheral neuropathy or other sensory disorders
• Diagnosed with vestibular or other balance disorder that impact walking
• Open wounds or active skin irritation on the leg shank
• Open wounds or active ulcers of either feet
• Unstable cardiovascular disease
• Unstable respiratory disease
• History of past or current deep vein thrombosis
• Active back pain that limits walking
• Use of supplemental oxygen to walk