To establish a nasal septum evaluation model before and after nasal septum deviation correction surgery with finite element analysis, to explore the effect of nasal septum cartilage stress reduction after nasal septum deviation correction surgery.

In this study, a male adult patient treated in Zhujiang Hospital of Southern Medical University in January 2022 was selected for second-line nasal endoscopic tension-reduction septum correction. Three-dimensional reconstruction and finite element analysis of nasal septum cartilage were performed before surgery and 6 months after surgery, and DICOM format data of three-dimensional CT were collected. Mimics 21.0, Geomagic Studio 2014, and ANSYS Workbench 17.0 software were used to establish a three-dimensional finite element model of the nasal septum, and fixed constraints were set on the top and bottom of the nasal septum cartilage. A contact stress with a pressure of 10⁶ Pa along the X axis was applied in the front plane of the cartilage, and then the finite element analysis of the total deformation displacement and von Mises stress (VMS) distribution of the nasal septum was performed.

(1) The maximum value of the total deformation displacement of the deviated nasal septum cartilage was located in the front of the cartilage, and the maximum value was 0.022 296 m before surgery and 0.108 810 m after surgery. (2) The stress distribution of deviated nasal septum cartilage was mainly concentrated in the anterior cartilage, in which VMS had a peak at the anterior end of the nasal septum, and the VMS peak was 725 000 Pa before surgery and 2 426 000 Pa after surgery. (3) The total deformation displacement and VMS value curves of the nasal septum showed a "waterfall" drop from the anterior end of the nasal septum to the posterior end. (4) The maximum distribution range of VMS in the nasal septum was 0.003 252 4 m² before surgery and 0.000 418 6 m² after surgery, indicating that the stress distribution range of the nasal septum after surgery was significantly reduced compared with that before surgery.

The three-dimensional finite element model of nasal septum is established successfully through CT three-dimensional reconstruction and finite element analysis. By comparing the total deformation displacement and VMS curve before and after the operation, this model evidenced that the correction of nasal deviation has the effect of reducing the stress of nasal septum cartilage.

Finite element analysis; Deviation of nasal septum; CT three-dimensional reconstruction; Biomechanics