Comparison of medial and lateral locking plates for Schatzker type Ⅵ fractures of tibial plateau: a finite element analysis / 中华创伤骨科杂志

ABSTRACT

Objective To compare the biomechanical characteristics of medial and lateral locking plates for Schatzker typeⅥfractures of tibial plateau by finite element analysis. Methods A 38 year-old male volunteer was enrolled for CT scan of his lower limbs. His CT images of the left tibial plateau were used for 3D reconstruction of a model of Schatzker type Ⅵ fracture by NX 9.0 software. After the boundary con-ditions were set, a 500 N load was applied to the tibial plateau to simulate the stress on a single leg when an adult weighing 60 kg walked. The displacement and stress on plate and screws were analyzed by Abaqus software. Results The ultimate stress on the model fixated with a medial locking plate was 81.7 MPa, located at the proximal tibiofibular joint surface. The ultimate stress on the model fixated with a lateral locking plate was 487.4 MPa, located at the junction of plate and screws. The ultimate stress on the fibula was much larger in the model fixated with a medial locking plate than in the model fixated with a lateral locking plate. The ultimate displacement was smaller and more homogeneous in the model fixated with a medial locking plate (1.15 mm) than in the model fixated with a lateral locking plate (3.44 mm).Conclusion The Schatzker type Ⅵ fractures of tibial plateau should be fixated with a medial locking plate because it has more biomechanical advantages than a lateral locking plate.