What clinical characteristics and radiographic parameters are associated with patellofemoral instability after kinematically aligned total knee arthroplasty

Introduction Thirteen patients presented with patellofemoral instability out of 3212 knees treated with kinematically aligned total knee arthroplasty (KA TKA) during a nine year period. We determined the clinical characteristics and post-operative radiographic parameters associated with patellofemoral instability, and whether re-operation and patient reported outcome measures are different between patients with and without patellofemoral instability.