Chinese Journal of Tissue Engineering Research ›› 2021, Vol. 25 ›› Issue (27): 4271-4276.doi: 10.12307/2021.181

Previous Articles     Next Articles

Biomechanical properties of reverse obliquity intertrochanteric fracture in the elderly treated with three different intramedullary fixations of ZNN nail, Gamma 3 nail and InterTan nail

Chen Jian, Ma Jianxiong, Lu Bin, Bai Haohao, Wang Ying, Ma Xinlong   

  1. 1Department of Orthopedics, People’s Hospital of Xuancheng City, Xuancheng 242000, Anhui Province, China; 2Department of Orthopedics Research, Tianjin Hospital, Tianjin 300050, China
  • Received:2020-10-31 Revised:2020-11-03 Accepted:2020-12-14 Online:2021-09-28 Published:2021-04-10
  • Contact: Ma Xinlong, Professor, Doctoral supervisor, Department of Orthopedics Research, Tianjin Hospital, Tianjin 300050, China
  • About author:Chen Jian, Doctoral candidate, Associate chief physician, Department of Orthopedics, People’s Hospital of Xuancheng City, Xuancheng 242000, Anhui Province, China
  • Supported by:
    the National Natural Science Foundation of China, No. 81871777 (to MXL), No. 11772226 (to MJX); the Science and Technology Program of Tianjin, No. 18PTLCSY00070, 16ZXZNGX00130 (to MXL); the General Financial Grant from the China Postdoctoral Science Foundation, No. 2017M621087 (to MJX); Grants from Postdoctoral Innovation Project of Tianjin, No. TJQYBSH2017017 (to MJX)

Abstract: BACKGROUND: Intramedullary nail Gamma 3, compression interlocking intramedullary nail InterTan and intramedullary nail ZNN have good clinical effect in the treatment of intertrochanteric fractures, but the difference of mechanical stability of three kinds of implants is not clear.  
OBJECTIVE: To perform biomechanical properties of anatomical intramedullary nail ZNN, intramedullary nail Gamma 3 and compression interlocking intramedullary nail InterTan for elderly reverse obliquity intertrochanteric fractures.
METHODS:  Three-dimensional finite element analysis was carried out to unstable intertrochanteric fractures models (AO31-A3.1) which fixed with ZNN, Gamma 3 and InterTan. The observed indicators were the distribution, maximum value and position of the Von Mises stress and the displacement, maximum value and position and the maximum crack distances of the fracture surface of the model.  
RESULTS AND CONCLUSION: (1) The peak values of stresses of the implant in the three groups were 364.8 MPa (ZNN), 364.9 MPa (Gamma 3) and 97.01 MPa (InterTan); the stress was lowest in the model InterTan. (2) The peak values of stresses of the femur of the three groups were 171.8 MPa (ZNN), 824.8 MPa (Gamma 3) and 29.51 MPa (InterTan); the stress was highest in the model Gamma 3. (3) The maximum amount of displacement was 3.768 mm in model ZNN, 3.862 mm in model Gamma 3 and 3.542 mm in model InterTan. Their locations were the same which located in the femoral head vertex. The maximum crack distances of the fracture surface of models were 0.08 mm, 0.09 mm and 0.02 mm in ZNN, Gamma 3 and InterTan, respectively. The maximum amount of displacement and the maximum crack distances were obviously smaller in model InterTan than in models ZNN and Gamma 3. (4) For reverse obliquity intertrochanteric fractures, finite element analysis showed that the InterTan implant provided significantly resistance to femoral head varus collapse, with the best mechanical properties, followed by ZNN internal fixation, and finally Gamma 3 internal fixation.

Key words: implant, internal fixation, finite element analysis, reverse obliquity intertrochanteric fracture, fracture fixation, intramedullary nail

CLC Number: