Finite element analysis of three internal fixations for the posteromedial split fracture fragment in tibial plateau fractures

Posteromedial tibial plateau fracture is one of the most challenging traumatic fractures. We aimed to compare and explain the biomechanical advantages and disadvantages of different internal fixation methods for the treatment of the posteromedial split fracture fragment in tibial plateau fractures. Finite element models of the tibial plateau fracture were constructed. Three different internal fixations were developed to treat the posteromedial split fracture fragment in tibial plateau fractures finite element models: (a) the novel anatomic locking plate fixation model, (b) the common anatomic locking plate fixation model, and (c) the reconstruction plate fixation model. We applied the same loading conditions to each model: 320 N axial compression. Under the same condition, the von Mises stress (VMS) and displacement distribution of the three internal fixations and tibia plateau were studied. The stress values of the novel anatomic locking plate are lower than the common anatomic locking plate and the reconstruction plate. Additionally, the novel anatomic locking plate fixation system exhibits smaller maximum displacement. In conclusion, our study indicated that the novel anatomic locking plate resulted in a lower stress distribution in the plate and screws, and better stability than the common anatomic locking plate and the reconstruction plate for the posteromedial split fracture fragment in tibial plateau fractures fixation under the same loading conditions. Thus, for the posteromedial split fracture fragment in tibial plateau fractures, the use of the novel anatomic locking plate internal fixation is recommended.