Novel 3D-navigated screw corridors for posterior pelvic ring stabilization: a finite element analysis.

PURPOSE: Posterior pelvic ring stabilization is technically demanding due to the complex local anatomy and limited osseous corridors. Advances in 3D navigation may allow for new screw trajectories previously infeasible with conventional fluoroscopy.

METHODS

A finite element model (FE) of a pelvis (Synbone LSS4060/Hard®) was developed, simulating seven screw configurations, including three novel oblique navigated pathways (Variants III-V). A 600 N vertical load was applied to simulate bipedal stance. Stress distribution and von Mises stresses were compared among configurations.

RESULTS

Conventional transsacral screws (Variants I-II) demonstrated the most uniform stress distribution and lowest peak stresses (7.17 MPa). Among novel configurations, Variant III achieved favorable compressive load transfer and lower shear stresses. Variant IV exhibited the highest overall stress (17.80 MPa), while Variant V demonstrated intermediate behavior.

CONCLUSION

The proposed 3D-navigated oblique screw pathways are anatomically feasible and may offer biomechanical advantages under certain conditions. These findings support further validation using cadaveric and clinical studies.