The Unstable Kneecap - the Impact of Anatomy on Function

Participants will be asked to walk on an instrumented treadmill. The study group will undergo gait analysis before surgery and 6 months after surgery. The control group will undergo gait analysis at one visit only.

Participants in the study group will undergo electromyography before and 6 months after surgery. Participants in the control group will undergo electromyography at one visit only

Participants in the study group will undergo intra-operative tracking and pressure measurements to see if corrective surgery to stabilise the patella improves tracking and pressure measurements