Abstract

Background
Distal spiral fractures of the tibial shaft present fixation challenges, particularly in patients who are not suitable candidates for intramedullary nailing. This study evaluated the biomechanical stability of medial minimally invasive percutaneous plating osteosynthesis (MIPO) under various physiological loading conditions.
Methods
A finite-element model of a distal AO/OTA 42-A1.1c spiral fracture of the tibia was created using computed tomography data. A precontoured titanium medial distal tibia locking compression plate with nine locking screws was simulated. Material properties were assigned to cortical and cancellous bone. The loading conditions included axial compression (750 N), varus/valgus bending (300 N at a 9° offset), and internal/external torsion (7.5 N·m). von Mises stress and fracture displacement were analyzed.
Results
Axial loading produced a peak plate stress of 508.06 MPa and a displacement of 2.17 mm. Valgus and varus loading generated stresses of 490.17 MPa and 324.08 MPa, respectively, with corresponding displacements of 3.86 mm and 2.01 mm. External and internal torsion resulted in stresses of 354.23 MPa and 358.9 MPa, respectively, with corresponding displacements of 2.64 mm and 2.22 mm.
Conclusions
Medial distal tibial plating demonstrated favorable biomechanical performance in this finite-element model; however, clinical extrapolation should be made cautiously.

• Keywords: Finite element analysis; Tibial fractures; Biomechanical phenomena; Mechanical stress