Can FEM-based preoperative planning for complex tibial plateau fractures improve surgical skills? A cadaver study

Complex tibial plateau fractures continue to pose a significant challenge for surgeons. In recent years, the widespread use of CT imaging has led to new insights leading to novel classifications that facilitate 360° stabilization techniques. Visualization in 3D has improved both fracture reduction and surgical outcomes. This study investigated whether preoperative planning of complex tibial plateau fracture fixation via finite element modeling (FEM) could enhance the fixation performance achieved by experienced surgeons and potentially improve outcomes for less experienced surgeons.

In twelve left cadaveric fresh-frozen human knees with intact soft tissue reproducible Schatzker type IV fractures with lateral depression were created. The samples were paired on the basis of bone mineral density and then randomly allocated into two groups. Six senior surgeons with extensive experience in the operative treatment of tibial plateau fractures performed two procedures: one using standard preoperative planning and one using FEM-optimized fixation planning. All fractures were stabilized with a medial locking plate and supplemental single screws when needed. The operation time, radiation dose and implant usage were documented. Surgeon mental workload was measured by the NASA task load index. Finally, the samples were biomechanically tested over four quasistatic load ramps from 10 to 200 N, followed by a cyclic sinusoidal load with increasing load level until failure. Failure was defined as either ≥ 5° varus/valgus malalignment or a vertical impression of the condyles ≥ 3 mm. The initial stiffness and load to failure were assessed via a 3D motion tracking system. Statistical analysis was conducted using Student's t-tests.

No significant differences were observed in terms of operative time or intraoperative radiation exposure. However, the NASA-TLX mental demand test revealed a statistically significant advantage for the FEM-planned group (33 ± 12.4 vs. 49 ± 8.6 (p = 0.043)), indicating a reduced cognitive load. Additionally, the FEM group exhibited superior biomechanical performance, with a higher load to failure of 1050 ± 535 N vs. 442 ± 226 N (p = 0.041).

This biomechanical feasibility study demonstrated that FEM-based preoperative planning is feasible and easy to implement for complex tibial plateau fractures. This planning supports specialized surgeons in challenging operations and can improve the stability of osteosynthesis.