Dynamic parallel traction theoretical model for the application and validation in femoral neck fractures - a finite element analysis

Jiarui Li; Kunyue Xing; Wenzhuo Wang; Li Sun; Linyuan Xue; Jiyao Xing; Xiaolin Wu; Dongming Xing

doi:10.1016/j.jor.2024.10.057

Dynamic parallel traction theoretical model for the application and validation in femoral neck fractures - a finite element analysis

J Orthop. 2024 Nov 5:64:7-12. doi: 10.1016/j.jor.2024.10.057. eCollection 2025 Jun.

Authors

Jiarui Li^{1

2}, Kunyue Xing³, Wenzhuo Wang^{1

4}, Li Sun¹, Linyuan Xue¹, Jiyao Xing¹, Xiaolin Wu¹, Dongming Xing^{1

5}

Affiliations

¹ The Affiliated Hospital of Qingdao University, Qingdao Cancer Institute, Qingdao University, Qingdao, 266071, China.
² College of Computer Science and Technology, Qingdao University, Qingdao, 266071, China.
³ Institute of Health Informatics, Faculty of Population Health Sciences, University College London, London, E14 5AA, United Kingdom.
⁴ College of Electrical Engineering, Qingdao University, Qingdao, 266071, China.
⁵ School of Life Sciences, Tsinghua University, Beijing, 100084, China.

PMID: 39651341
PMCID: PMC11617892 (available on 2026-06-01)
DOI: 10.1016/j.jor.2024.10.057

Abstract

Study objective: This study aims to validate the application effects of a novel theoretical model of dynamic parallel traction in the treatment of femoral neck fractures through three-dimensional finite element analysis. By simulating the femoral neck fracture model, we explore the promotional effect of dynamic parallel traction on fracture healing.

Method: A digital 3D femur model was constructed using high-resolution computed tomography data of the lower limbs of a 70-year-old elderly subject. An axial compression of 500N was applied at different traction angles (0°, 10°, 20°, 30°, 40°, 50°). The equivalent stress distribution and deformation of the femur geometric model were calculated at each angle under the six $α$ angles. Statistical analysis was performed using One-Way ANOVA.

Results: At the parallel angle ( $α$ = 0°), the maximum stress on the entire femur occurred at the trochanteric fossa, with a value of 7.945 MPa ( $α$ = 0°). The maximum deformation was at the fovea capitis, with a value of 104.13 mm ( $α$ = 0°). As the traction angle gradually increased ( $α$ = 10°, $α$ = 20°, $α$ = 30°, $α$ = 40°, $α$ = 50°), the maximum stress shifted gradually to the medial cortex of the femoral shaft, with values of 11.236 MPa ( $α$ = 10°), 15.196 MPa ( $α$ = 20°), 19.263 MPa ( $α$ = 30°), 23.149 MPa ( $α$ = 40°), and 26.311 MPa ( $α$ = 50°). The maximum deformation remained at the fovea capitis but increased to 131.87 mm ( $α$ = 10°), 181.96 mm ( $α$ = 20°), 228.2 mm ( $α$ = 30°), 271.15 mm ( $α$ = 40°), and 307.41 mm ( $α$ = 50°). One-Way ANOVA revealed that traction angle significantly influenced the stress distribution (F = 4.419, p = 0.0022) and deformation magnitude (F = 4.023, p = 0.0040) at the proximal femur, indicating that traction angle is a critical factor affecting stress distribution and deformation.

Conclusion: With the increase of the traction angle, the mechanical properties of the proximal femur decrease, indicating an increased risk of non-union and complications. Additionally, the study proves the effectiveness of the "dynamic parallel traction" theory.

Keywords: Dynamic parallel traction; Femoral neck fracture; Finite element analysis; New hypothesis.