Numerical Optimization of the Position in Femoral Head of Proximal Locking Screws of Proximal Femoral Nail System; Biomechanical Study

Abstract

Background: Proximal femoral fracture rates are increasing due to osteoporosis and traffic accidents. Proximal femoral nails are routinely used in the treatment of these fractures in the proximal femur. Aims: To compare various combinations and to determine the ideal proximal lag screw position in pertrochanteric fractures (Arbeitsgemeinschaft für Osteosynthesefragen classification 31-A1) of the femur by using optimized finite element analysis. Study Design: Biomechanical study. Methods: Computed tomography images of patients" right femurs were processed with Mimics. Afterwards a solid femur model was created with SolidWorks 2015 and transferred to ANSYS Workbench 16.0 for response surface optimization analysis which was carried out according to anterior-posterior (-10°0) and posterior-anterior directions of the femur neck significantly increased these stresses. The most suitable position of the proximal lag screw was confirmed as the middle of the femoral neck by using optimized finite element analysis.

Keywords

• Femoral neck fractures, biomechanics, finite element analysis

Kaynakça

1. 1. Mereddy P, Kamath S, Ramakrishnan M, Malik H, Donnachie N. The AO/ ASIF proximal femoral nail antirotation (PFNA): a new design for the treatment of unstable proximal femoral fractures. Injury 2009;40:428-32.
2. 2. Verheyden AP, Josten C. Intramedullary Fixation of Intertrochanteric Fractures with the Proximal Femoral Nail (PFN). Operat Orthop Traumatol 2003;15:20-37.
3. 3. Sener M, Onar V, Kazlmoğlu C, Yağdi S. [Mortality and morbidity in elderly patients who underwent partial prosthesis replacement for proximal femoral fractures]. Eklem Hastalik Cerrahisi 2009;20:11-7.
4. 4. Curtis MJ, Jinnah RH, Wilson V, Cunningham BW. Proximal femoral fractures: a biomechanical study to compare intramedullary and extramedullary fixation. Injury 1994;25:99-104.
5. 5. Kuzyk PR, Zdero R, Shah S, Olsen M, WaddellJP, Schemitsch EH. Femoral head lag screw position for cephalomedullary nails: a biomechanical analysis. J Orthop Trauma 2012;26:41-21.
6. 6. Wu X, Yang M, Wu L, Niu W. A Biomechanical Comparison of Two Intramedullary Implants for Subtrochanteric Fracture in Two Healing Stages: A Finite Element Analysis. Appl Bionics Biomech 2015:1-7.
7. 7. Oken OF, Soydan Z, Yildirim AO, Gulcek M, Ozlu K, Ucaner A. Performance of modified anatomic plates is comparable to proximal femoral nail, dynamic hip screw and anatomic plates: finite element and biomechanical testing. Injury 2011;42:1077-83.
8. 8. Azboy I, Demirtaş A, Gem M, Cakır IA, Tutak Y. A comparison of proximal femoral locking plate versus 95-degree angled blade plate in the treatment of reverse intertrochanteric fractures. Eklem Hastalik Cerrahisi 2014;25:15-20.

9. 9. Hrubina M, Horák Z, Bartoška R, Navrátil L, Rosina J. Computational modeling in the prediction of Dynamic Hip Screw failure in proximal femoral fractures. J Appl Biomed 2013;11:143-51.
10. 10. Goffin JM, Pankaj P, Simpson AH. The importance of lag screw position for the stabilization of trochanteric fractures with a sliding hip screw: a subject-specific finite element study. J Orthop Res 2013;31:596-600.
11. 11. Kuzyk P, Higgins G, Zedero R, Shah S, Olsen M, Wadell J, et al. Femoral head lag screw position for cephalomedullary nails: a biomechanical analysis. J Orthop Trauma 2012;26:414-21.
12. 12. Kashigar A, Vincent A, Gunton MJ, Backstein D, Safir O, Kuzyk PR. Predictors of failure for cephalomedullary nailing of proximal femoral fractures. Bone Joint J 2014;96:1029-34.
13. 13. Baumgaertner MR, Solberg BD. Awareness of tip-apex distance reduces failure of fixation of trochanteric fractures of the hip. J Bone Joint Surg Br 1997;79:969-71.
14. 14. Seral B, García JM, Cegoñino J, Doblaré M, Seral F. Finite element study of intramedullary osteosynthesis in the treatment of trochanteric fractures of the hip: Gamma and PFN. Injury 2004;35:130-5.
15. 15. Mei J, Liu S, Jia G, Cui X, Jiang C, Ou Y. Finite element analysis of the effect of cannulated screw placement and drilling frequency on femoral neck fracture fixation. Injury 2014;45:2045-50.
16. 16. Kilickap, E. and Huseyinoglu M. Optimization and modelling of burrheight by using response surface methodology and genetic algorithm in drilling AISI 316. J Eng Fac Eng Dicle Univ 2010;1:71-80.
17. 17. Gundle R, Gargan MF, Simpson AH. How to minimize failures of fixation of unstable intertrochanteric fractures. Injury 1995;26:611-4.
18. 18. Kane P, Vopat B, Heard W, Thakur N, Paller D, Koruprolu S, et al. Is tip apex distance as important as we think? A biomechanical study examining optimal lag screw placement. Clin Orthop Relat Res 2014;472:2492-8.
19. 19. Regling M, BlauA, Probe RA, Maxey JW, Solberg BD. Improved lag screw positioning in the treatment of proximal femur fractures using a novel computer assisted surgery method: a cadaveric study. BMC Musculoskelet Disord 2014;15:189.
20. 20. Munemoto M, Kido A, Sakamoto Y, Inoue K, Yokoi K, Shinohara Y, et al. Analysis of trabecular bone microstructure in osteoporotic femoral heads in human patients: in vivo study using multidetector row computed tomography. BMC Musculoskelet Disord 2016;17:13.
21. 21. Min BW, Lee KJ, Bae KC, Lee SW, Lee SJ, Choi JH. Result of Internal Fixation for Stable Femoral Neck Fractures in Elderly Patients. Hip Pelvis 2016;28:43-8.