Failed Patellofemoral Instability Surgery: A Practical Guide to Diagnosis and Revision

Recurrent patellofemoral instability (PFJI) can result in significant pain, functional limitations, and surgical failure. A thorough understanding of the reasons for such failures is crucial for developing effective revision strategies. This article offers a comprehensive guide to diagnosing and managing failed patellofemoral stabilization surgery, highlighting the multifactorial nature of PFJI and the importance of avoiding a "one-size-fits-all" approach. It explores common pitfalls, including over-reliance on unreliable metrics and technical errors during ligament reconstruction. The paper details practical surgical techniques, such as medial patellofemoral ligament (MPFL), medial patellotibial ligament (MPTL), and medial quadriceps tendon-femoral ligament (MQTFL) reconstruction, and outlines key considerations for tibial tubercle osteotomy and trochleoplasty. A structured diagnostic pathway is proposed to help identify the root cause of surgical failure and ensure a tailored approach to revision.