Functional positioning in robotic patello-femoral arthroplasty: a step-by-step technique

Patello-femoral arthroplasty (PFA) is an effective treatment option for isolated patello-femoral osteoarthritis. However, challenges remain regarding implant positioning and patellar tracking. Recent advances in implant design and robotic-assisted techniques have contributed to more personalized and reproducible procedures. Functional positioning (FP), a three-dimensional alignment concept, introduces a customized approach to optimize trochlear resurfacing and restore joint kinematics of the anterior compartment. This article presents a step-by-step surgical technique for PFA using FP principles in combination with an image-based robotic system. The technique ensures accurate preoperative planning, real-time intraoperative adjustments, and precise component placement. The key steps of this surgical technique include trochlear resurfacing assisted by an image-based robotic system and the restoration of patellar tracking, following a step-by-step approach that is both effective and reproducible. The use of FP enables personalized anterior compartment restoration, avoiding overstuffing and improving patellar tracking. Future studies will help refine FP strategies and further optimize outcomes in these patients.