Biomedical Study Through Numerical Simulations of Odontoid Fracture—Comparison of the Odontoid With and Without Fracture After Treatment: A Finite Element Model Analysis

Type II odontoid fracture represents one of the most frequent and complex injuries of the upper cervical spine, posing a major challenge both in diagnosis and in surgical management. Despite advances in surgical fixation techniques, the choice of optimal treatment remains a matter of debate, especially in patients with low bone density or unfavorable anatomical characteristics. The aim of this study was to biomechanically analyze, through finite element numerical simulations (finite element model [FEM]), the different phases of surgical treatment of type II odontoid fracture, comparing the structural response of the C2 vertebra in three clinical scenarios: healthy vertebra, immediate postoperative phase following posterior C1–C2 fixation, and intermediate healing phase with partial bone fusion. For this purpose, precise three-dimensional models were developed from computed tomography scans of real patients, which were subjected to loading conditions representative of both physiological and high biomechanical stress situations. The simulations allowed identification of critical zones of stress and strain concentration, highlighting the vulnerability of the odontoid base in the early postoperative phases and the importance of callus evolution in load redistribution. Furthermore, the decisive influence of bone quality on the biomechanical integrity of the construct was demonstrated, with osteoporotic models being more susceptible to fixation failure and excessive deformation. The results obtained provide a valuable tool for personalized surgical planning, optimizing the choice of fixation type and immobilization protocol according to the individual characteristics of each patient. This work reinforces the usefulness of FEM simulation as a support tool in clinical decision-making.