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

Abstract

Abstract Purpose 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. Methods Finite element models of the tibial plateau fracture were constructed. And 3 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, 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 3 internal fixations and tibia plateau were studied. Results The stress values of the novel anatomic locking plate were lower than the common anatomic locking plate and the reconstruction plate. And the novel anatomic locking plate fixation system also has smaller maximum displacement. The peak stress value on the maximal stress point in the fracture fragment, tibia, plate and screws with model a, b, and c were 1.327 MPa vs. 1.164 MPa vs. 0.835 MPa, 27.64 MPa vs. 24.985 MPa vs. 23.437 MPa, 108.648 MPa vs. 123.298 MPa vs. 163.541 MPa, and 69.234 MPa vs. 86.547 MPa vs. 99.214 MPa, respectively. The maximum displacement of the tibia, plate and screws with model a, b, and c were 0.693 mm vs. 0.758 mm vs. 0.832 mm, 0.665 mm vs. 0.727 mm vs. 0.795 mm, and 0.615 mm vs. 0.732 mm vs. 0.751 mm, respectively. Conclusions 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.