TY - JOUR
T1 - Fixation effects of different types of cannulated screws on vertical femoral neck fracture
T2 - A finite element analysis and experimental study
AU - Zhan, Shi
AU - Jiang, Dajun
AU - Ling, Ming
AU - Ding, Jian
AU - Yang, Kai
AU - Duan, Lei
AU - Tsai, Tsung Yuan
AU - Feng, Yong
AU - van Trigt, Bart
AU - Jia, Weitao
AU - Zhang, Changqing
AU - Hu, Hai
N1 - Accepted Author Manuscript
PY - 2021
Y1 - 2021
N2 - Femoral neck fractures (FNFs) in young patients usually result from high-energy violence, and the vertical transcervical type is typically challenging for its instability. FNFs are commonly treated with three cannulated screws (CS), but the role of screws type on fixation effects (FE) is unclear. The purpose of this study was to evaluate the FE of ten types of CS with different diameters, lengths, depths, and pitches of thread via finite element analysis which was validated by a biomechanical test. Ten vertical FNF models were grouped, fixed by ten types of CS, respectively, all in a parallel, inverted triangular configuration. Their FE were scored comprehensively from six aspects via an entropy evaluation method, as higher scores showed better results. For partial-thread screws, thread length and thread shape factor (TSF) are determinative factors on stability of FNF only if thread depth is not too thick, and they have less cut-out risk, better compression effects and better detached resistance of fracture than full-thread screws, whereas full-thread screws appear to have better shear and shortening resistance. A combination of two superior partial-thread screws and one inferior full-thread screw for vertical FNF may get optimal biomechanical outcomes. The type of cannulated screw is important to consider when treating vertical FNF.
AB - Femoral neck fractures (FNFs) in young patients usually result from high-energy violence, and the vertical transcervical type is typically challenging for its instability. FNFs are commonly treated with three cannulated screws (CS), but the role of screws type on fixation effects (FE) is unclear. The purpose of this study was to evaluate the FE of ten types of CS with different diameters, lengths, depths, and pitches of thread via finite element analysis which was validated by a biomechanical test. Ten vertical FNF models were grouped, fixed by ten types of CS, respectively, all in a parallel, inverted triangular configuration. Their FE were scored comprehensively from six aspects via an entropy evaluation method, as higher scores showed better results. For partial-thread screws, thread length and thread shape factor (TSF) are determinative factors on stability of FNF only if thread depth is not too thick, and they have less cut-out risk, better compression effects and better detached resistance of fracture than full-thread screws, whereas full-thread screws appear to have better shear and shortening resistance. A combination of two superior partial-thread screws and one inferior full-thread screw for vertical FNF may get optimal biomechanical outcomes. The type of cannulated screw is important to consider when treating vertical FNF.
KW - Biomechanics
KW - Finite element analysis
KW - Types of screws
KW - Vertical femoral neck fracture
UR - http://www.scopus.com/inward/record.url?scp=85116442319&partnerID=8YFLogxK
U2 - 10.1016/j.medengphy.2021.09.007
DO - 10.1016/j.medengphy.2021.09.007
M3 - Article
AN - SCOPUS:85116442319
SN - 1350-4533
VL - 97
SP - 32
EP - 39
JO - Medical Engineering and Physics
JF - Medical Engineering and Physics
ER -
