Comparison of Lateral and Medial Plate Fixations of Talar Neck Fracture: A 3D-Finite Element Analysis

Abstract

Background: Talar neck fractures are rare, but challenging injuries, because the bone has unique anatomy, and its blood supply makes it difficult to stabilize the fracture and is likely to cause posttraumatic or postoperative complications. Thanks to development of appropriately sized plates, outcomes of plate fixation of talar neck fractures have been improved compared with screw fixation. Although some studies have demonstrated no difference between screw only fixation and screw-plate constructs, authors have not compared medial and lateral plating in terms of stability. The aim of this study was to find biomechanical characteristics of fixations including medial plating and lateral plating. Method: On the basis of CT scans of the tibia, fibula, talus and medial or lateral plate with screws, 3D-finite element models of right simple fractures of talar neck stabilized by medial plate or lateral plate were built to compare their biomechanical characteristics with ANSYS WORKBENCH programme when applied 3 types of loads including axial compression, antero-posterior bending and torsion. Results: There were no significant differences in displacements at fracture sites between the medial and lateral plate fixations under all of the loads, but the latter produced stiffness of 0.86Mpa and 1.66Mpa and the former presented 1.21Mpa and 2.11Mpa under axial compression and torsion loads for talar neck fractures. Conclusion: For talar neck fractures, lateral plate fixation provides greater stability than medial plate fixation.