Overview

This study investigates how well individuals with knee osteoarthritis can learn to alter their calf muscle activation using haptic biofeedback while walking and evaluates how these changes affect knee loading.

Prior research has utilized musculoskeletal simulations to determine that reducing the activation of one of the calf muscles, the gastrocnemius, can have a large impact on reducing knee loading. However, this has not been tested in individuals with knee osteoarthritis. In this study, participants will be trained to alter the activation of their gastrocnemius muscle, by receiving haptic feedback after each step. The feedback will indicate how the participant changed their muscle activation relative to baseline. Some participants will train on a treadmill in the laboratory for up to two sessions, with 30 minutes of walking with feedback in each session. If a participant can learn to adjust their muscle activation in the first training session, they will be able to complete the second training session. Other participants will train outside the laboratory for one session with 30 minutes of walking with feedback to investigate changes in knee loading while using the new walking strategy during over-ground walking.

The movement data collected during the training sessions will be used as inputs to computer simulations of the musculoskeletal system to determine if walking with the new muscle activation strategy reduces knee loading.

Eligibility

Inclusion Criteria:

• Medial and/or lateral compartment knee osteoarthritis
• Diagnosed with knee osteoarthritis of at least six months duration
• Ambulatory without aids
• Able to walk for at least 60 minutes
• Typical pain rating less than or equal to 4 on scale of 0-10
• Able to reduce gastrocnemius muscle activation by 10% from baseline

Exclusion Criteria:

• History of symptomatic arthritis in lower limb joints other than the knees
• Replacement of any lower extremity joint
• Symptoms originating from the patellofemoral joint
• Body mass index equal to or greater than 35
• Nerve or muscle disease associated with walking difficulty
• History of rheumatoid arthritis, gout, or autoimmune disease
• History of lower limb fracture or surgery requiring hospitalization
• Pregnant