A finite element analysis of loading velocity affecting femoral neck fracture propagation

doi:10.3969/j.issn.2095-4344.1180

Abstract

Abstract:

BACKGROUND: It is a dynamic development in fracture, but the traditional finite element method cannot precisely predict the fracture initiation, crack process, the stress, strain and crack propagation.

OBJECTIVE: To simulate and investigate the influence of fall load velocity on crack propagation in femoral neck fracture.

METHODS: CT data of femur from a healthy volunteer were collected and imported to Mimics 19.0 software, after region growing, editing, smoothing and wrapping, a three-dimensional finite element model of proximal femur was created. The primary model was imported in Hypermesh 14.0 for meshing of trabecular and cortical bone, defining material properties, setting boundary conditions, simulating fall in internal rotation and adduction, and loaded with load-time function (F1=2 500t; F2=(10 000/3)t; F3=5 000t; F4=10 000t). The integrated K file was finally calculated in LS-DYNA.

RESULTS AND CONCLUSION: (1) The initial crack started at the inferior-posterior of femoral neck with a velocity-dependent manner in primary length. (2) The maximum stress distributed on the inferior-posterior of femoral neck but with a negative correlation between loading velocity in distributing region from intertrochanteric to neck. (3) The compressive strain mainly demonstrated on the inferior-posterior of femoral neck that consistent with the propagation of crack. (4) Higher the loading rate was, earlier the damage began, fewer the time needed to fracture, faster the crack developed, and rougher the fracture line were and larger the Pauwels angle formed. (5) In summary, fall loading rate is an important exogenous factor in femoral neck fracture propagation, which affects hip fracture types.

Key words: fall load velocity, femoral neck fracture, crack propagation, fracture mechanics, finite element, fall, CT data, subfemoral fracture

Funding: the National Natural Science Foundation of China, No. 81673996 (to LZL)

CLC Number:

R459.9|R318.01

Zheng Liqin, Lin Ziling, Chen Xinmin, Liang Ziyi, Li Musheng, Zheng Yongze. A finite element analysis of loading velocity affecting femoral neck fracture propagation[J]. Chinese Journal of Tissue Engineering Research, 2019, 23(20): 3148-3152.

Figures/Tables 4

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