The aim of the study was to assess the impact of a self aligning unidirectional mobile tibial bearing and the use of a patella button on lateral patella release rates within a knee system using a common femoral component for both the fixed and mobile variants. A total of 347 patients undergoing TKR were included in the study and randomly allocated to receive either a Mobile Bearing (171 knees) or a Fixed Bearing (176 knees) PS PFC Sigma TKR. Further sub-randomisation into patella resurfacing or retention was performed for both designs. The need for lateral patella release was assessed during surgery using the ‘no thumbs’ technique. The lateral release rate was similar for fixed bearing (9.65%) and mobile bearing (9.94%) implants (p=0.963). Patella resurfacing resulted in lower lateral release rates when compared to patella retention (5.8% vs 13.8%; p=0.0131). This difference was most marked in the mobile bearing group where the lateral release rate was 16.3% with patella retention compared to 3.5% with patella resurfacing (p=0.005).Aim
Methods and results
