[Avoidance of Patello-Femoral Overstuffing]

Reconstruction of the patello-femoral compartment and by that avoidance of an overstuffing is one of the important steps for a successful TKA. A revision rate of around 15 % due to problems of the patello-femoral compartment demonstrates that this is not achieved in all cases. There can be many reasons for an overstuffing and also the symptoms can be very variable, showing sometimes a limited flexion, patello-femoral maltracking or anterior knee pain. Due to its relevance the following paper demonstrates the different reasons for a patello-femoral overstuffing. Further possible solutions for avoidance of overstuffing are described. The reasons for patello-femoral overstuffing are multiple. The majority is caused on the femoral side, however additional patellar and tibial reasons exist. During positioning of the femora resection blocks, the distal resection plane (extension/flexion) as well as the AP block for sizing is crucial. For that a pre-op analysis and implant planning in the lateral view of the X-ray should be performed in order to optimise implant size and position. For the patella the correct resection height and plane are important to avoid an overstuffing. A lateral patella component position can be another reason for an overstuffing. In conclusion, it can be stated that an anatomic reconstruction of the patello-femoral compartment is an important part of TKA surgery. The avoidance of a patello-femoral overstuffing can be achieved by exact pre-op planning of the femoral component size and position, and by precise surgery with sufficient bone resection.