Patellofemoral resurfacing at total knee arthroplasty.

A retrospective review of 268 primary total knee arthroplasties (TKAs) with a mean follow-up of four years is presented. The patellae were resurfaced in all cases. There were six complications (2.2%) referable to the patellofemoral articulation: three subluxations, one patellar fracture, one loosening of a metal-backed patellar component, and one patellar tendon avulsion. Successful patellofemoral resurfacing (PFR) can be accomplished with minimal complications if the following technical considerations are met: 5-7 degrees of valgus alignment; medial placement of the patellar component; taking care not to increase either the AP diameter of the knee or the thickness of the patella; avoiding internal rotation of either the tibial or femoral components and proper soft tissue balancing. A thorough review of patellofemoral complications after TKA is presented, and technical considerations relevant to the successful performance of PFR are discussed.