Chinese Journal of Tissue Engineering Research ›› 2023, Vol. 27 ›› Issue (22): 3481-3485.doi: 10.12307/2023.347

Previous Articles     Next Articles

Biomechanical analysis of femoral neck system in unstable femoral neck fractures

Gu Ye1,  Wang Qiufei1,  Fang Tao1, Peng Yuqin1, Xue Feng1, Geng Dechun2, Xu Yaozeng2, Zhang Wen3   

  1. 1Department of Orthopedics, Changshu Hospital Affiliated to Suzhou University, Changshu No.1 People’s Hospital, Changshu 215500, Jiangsu Province, China; 2Department of Orthopedics, First Affiliated Hospital of Suzhou University, Suzhou 215006, Jiangsu Province, China; 3Institute of Orthopedics, Suzhou University, Suzhou 215006, Jiangsu Province, China 
  • Received:2022-04-18 Accepted:2022-06-06 Online:2023-08-08 Published:2022-11-02
  • Contact: Zhang Wen, Master, Senior experimentalist, Institute of Orthopedics, Suzhou University, Suzhou 215006, Jiangsu Province, China
  • About author:Gu Ye, MD, Associate chief physician, Department of Orthopedics, Changshu Hospital Affiliated to Suzhou University, Changshu No.1 People’s Hospital, Changshu 215500, Jiangsu Province, China
  • Supported by:
    the Key Research and Development (Social Development) Project of Jiangsu Province, No. BE2021673 (to GY); Key Research and Development (Social Development) Project of Jiangsu Province, No. BE2022666; Suzhou Science and Technology Development Plan Project, No. SYSD2020013 (to GY); Suzhou Municipal Clinical Key Disease Diagnosis and Treatment Project, No. LCZX201824 (to XF, GY); Changshu Municipal Health Commission Science and Technology Project, No. csws201907 (to GY); Changshu Science and Technology Development Plan Project, No. CS202119 (to WQF, GY); Changshu Science and Technology Development Plan Project, No. CS201817 (to GY) 

Abstract: BACKGROUND: The femoral neck system is a novel fixation device for unstable femoral neck fractures.
OBJECTIVE: To compare and analyze the mechanical stability of three kinds of internal fixation in Pauwels III unstable femoral neck fractures by finite element method. 
METHODS: On the basis of the validated femoral finite element model (intact group), the model was cut to make a Pauwels III 70° unstable fracture of the femoral neck. Different internal fixation models were implanted to simulate clinical surgery. This study established femoral neck system fixation (model A), inverted triangular cannulated screw fixation (model B) and 4 diamond-shaped cannulated screw fixation (model C). All the nodes under the distal end of the femur were restrained for the three groups of models, and 700 N, 1 400 N and 2 100 N compressive loads were applied to the femoral head. Through calculation and analysis, the Von Mises stress distribution and deformation of each group of models were observed, and the mechanical stability of each group of models was compared. 
RESULTS AND CONCLUSION: (1) The maximum deformation of the three groups of models under various loads occurred in the femoral head. When compressed for 2 100 N, the deformation of model A was 2.06 mm less than that of intact group 2.17 mm, while the deformations of model B and model C were both higher than that of intact group, with the distributions of 2.39 mm and 2.33 mm. (2) Under various loads, the stress in model A group was also the smallest. Under 2 100 N, the stress peak in model A was 297.31 MPa, distributed at the joint position of anti-rotation screw and locking screw, while the stress peak in model B was 543.18 MPa, distributed at the fracture joint position of the third screw in the inverted triangle. However, the deformation and stress of model C were intermediate between model A and model B, and the maximum stress peak value was distributed at the bottom hollow of the cannulated screw fracture, reaching 315.61 MPa at 2 100 N. (3) The compressive stiffness and stress analysis of models of the three groups showed that model A < model C < model B. (4) It is concluded that the mechanical stability of femoral neck system for femoral neck fracture is better than that of three and four cannulated screws fixation, and it can effectively prevent femoral neck shortening. Femoral neck system is a recommended internal fixation method for unstable femoral neck fractures.

Key words: femoral neck system, finite element analysis, femoral neck unstable fracture, femoral neck fracture, internal fixation

CLC Number: