Dynamic hip fracture modelling

Abstract

A treatment of neck of femur fractures is internal fixation using a dynamic hip screw. This article investigates the effect of the angle of such a dynamic hip screw on the stresses developed under loading in a human femur. The modelling is informed by an examination of Medicare Australia data which indicates that women aged 65~years or over are the primary recipients of an internal fixation of the neck of femur. Development of a series of finite element models with incremental changes in angle allows determination of the stresses developed in use. Regression analysis of the data obtained from the finite element analysis reveals a strong negative association between angle and stress. The results obtained will assist in the selection of dynamic hip screw angles appropriate for individual patients. References

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