Factors Influencing Graft Function following MPFL Reconstruction: A Dynamic Simulation Study

J Knee Surg DOI: 10.1055/s-0040-1702185Medial patellofemoral ligament (MPFL) reconstruction is currently the primary surgical procedure for treating recurrent lateral patellar instability. The understanding of graft function has largely been based on studies performed with normal knees. The current study was performed to characterize graft function following MPFL reconstruction, focusing on the influence of pathologic anatomy on graft tension, variations with knee flexion, and the influence on patellar tracking. Knee squatting was simulated with 15 multibody dynamic simulation models representing knees being treated for recurrent lateral patellar instability. Squatting was simulated in a preoperative condition and following MPFL reconstruction with a hamstrings tendon graft set to allow 0.5 quadrants of lateral patellar translation with the knee at 30 degrees of flexion. Linear regressions were performed to relate maximum tension in the graft to parameters of knee anatomy. Repeated measures comparisons evaluated variations in patellar tracking at 5-degree increments of knee flexion. Maximum graft tension was significantly correlated with a parameter characterizing lateral position of the tibial tuberosity (maximum lateral tibial tuberosity to posterior cruciate ligament attachment distance, r
2 = 0.73, p < 0.001). No significant correlations were identified for parameters related to trochlear dysplasia (lateral trochlear inclination) or patella alta (Catonâ€...

Source: Journal of Knee Surgery - March 5, 2020 Category: Orthopaedics Authors: Tanaka, Miho J. Cosgarea, Andrew J. Forman, Jared M. Elias, John J. Tags: Original Article Source Type: research