This research aims to explore differences in walking and functional movement mechanics, exercise response, and physical activity between people with osteoarthritis (OA), those who have undergone total joint replacement, and healthy individuals.

People living with OA tend to be less physically active than those without the disease, which is often due to pain, stiffness and joint instability. This reduction in physical activity can lead to additional health problems down the line. When the disease becomes severe, joint replacement surgeries are sometimes performed to relieve pain and improve individuals' quality of life. However, despite reducing pain, there is little evidence to show that joint replacement surgeries encourage individuals to return to healthy physical activity levels.

Reasons for the lack of change may include a failure to address unhealthy walking and movement patterns which could still be causing pain and instability and reduced physical fitness levels.

By investigating these reasons, we hope that findings from this study will help to inform future interventions that improve clinical outcomes and quality of life for individuals with OA and post-joint replacement.

Inclusion Criteria:

• Diagnosed symptomatic bilateral or unilateral knee osteoarthritis, self-reported ability to walk without an aid for 10 minutes and to ascend and descend stairs, no neurological conditions or other musculoskeletal pathology/injury which would impact walking gait.

Exclusion Criteria:

• Unable to walk at 0.8 m/s, exclusion based on IMO screening, non-English speaking, lacking ability to consent.

Local private physiotherapy clinics and local sports clubs