Coory J, et al. - Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) (1999-2017) was utilized for a study by the researchers in order to give long term outcomes for patellar resurfaced in comparison with when the patella is not resurfaced. In contrast with procedures where the patella was resurfaced, for all primary TKA, procedures where the patella was not resurfaced had a greater rate of revision. Unresurfaced posterior stabilized (PS) knees had the greatest cumulative percent revision at 17 years, followed by minimally stabilized (MS) unresurfaced, PS resurfaced and MS resurfaced. Inlay patellar resurfacing had a greater rate of revision vs onlay patellar resurfacing. Thus, for both MS and PS knees, resurfacing the patella decreased the rate of revision. Moreover, MS knees with patellar resurfacing had the least rate of revision. In comparison with inlay patella designs, onlay patella designs were correlated with a lower revision rate.