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Rethinking MPFL Graft Tensioning: A Conceptual Framework for Anatomy-Driven Dynamic Tensioning Beyond Force and
Jacek Walawski1,2, Oliwer Sygacz3,4, Łukasz Matuszewski4
1Ortosport Lublin, Jana Pawła II 13, 20-535 Lublin, Poland.
Abstract:
Medial patellofemoral ligament (MPFL) reconstruction is widely performed, yet its most critical step-graft tensioning-remains insufficiently defined. Many commonly described techniques rely on predefined force values or fixation angles derived largely from cadaveric studies and may not fully account for variability in patellofemoral anatomy, particularly in dysplastic knees. Persistent instability, stiffness, postoperative range-of-motion limitation, and patellofemoral overload nevertheless remain clinically relevant complications after MPFL reconstruction. This article re-examines the conceptual basis of MPFL graft tensioning and highlights the limitations of force- and/or angle-based approaches. We propose a shift toward anatomy-driven, dynamic, independent graft-arm tensioning, in which graft behavior is guided by trochlear morphology and intraoperative patellar tracking. The proposed objective is to restore physiologic patellar engagement within the trochlear groove across the range of motion rather than adjusting graft tension to reproduce predetermined mechanical parameters derived primarily from experimental studies. By prioritizing patient-specific anatomy and functional patellar tracking, this approach provides a testable conceptual framework for MPFL graft tensioning. No comparative clinical or biomechanical data currently demonstrate that this approach is superior to conventional force- or angle-based strategies. It is presented as a testable hypothesis, and prospective comparative validation is required before it can be recommended in practice.
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