Computationally Efficient, Explicit Finite Element Model for Evaluation of Patellofemoral Mechanics

Patient-specific finite element (FE) models can provide clinically relevant information about contact mechanics and kinematics that may be difficult or infeasible to obtain otherwise, and have potential to guide pre-operative planning. However, substantial uncertainty in model variables exists in patient-specific modeling, and suggests a probabilistic approach. Although efficient probabilistic methodology has been recently developed, multiple analyses are still required, and computational time for a fully deformable FE model throughout a flexion cycle has typically made this impractical. Therefore, the goal of the present study was to develop an explicit FE model of the patellofemoral joint with deformable cartilage and deformable, wrapping extensor tendons, and to compare kinematic and contact mechanics results with a model modified for computational efficiency. The efficient model incorporated rigid femoral and patellar cartilage representation with an optimized contact pressure–surface overclosure relationship, and composite-fiber tendons.