Yeroushalmi D, Zak S, Sharan M, et al. - This study was undertaken to explore whether retaining the original patellar button during a revision total knee arthroplasty (rTKA) using a different implant system affects patellar tracking. Between August 2011 and June 2019, researchers conducted a retrospective cohort study of rTKA patients at an urban, tertiary referral center. Individuals were categorized into two cohorts depending on whether their retained patella from their primary TKA was of the same (SIM) or different implant manufacturer (DIM) as the revision system applied. They conducted radiographic measurements on pre and post-operative knee radiographs and differences were compared between the two groups. A total of 293 consecutive patients were included in the study. There were no clinically significant variations in patellar tracking when the original patellar component was retained and a different revision implant system was applied. Given the inherent risks of bone loss and fracture with patellar component revision, the study demonstrated that surgeons performing rTKA may retain the primary patella whether it is well fixed and can still expect appropriate patellar tracking regardless of the revision implant system used.