Hip fracture is one of the most commonly sustained fractures and the frequency is increasing with the aging population
engineering
Description
ABSTRACT
Hip fracture is one of the most commonly sustained fractures and the frequency is increasing
with the aging population. Depending on the hip fracture location, it is classified into femoral
neck fracture or intertrochanteric fracture. Therefore, the choice of implants needs to be
selected appropriately. Two set of finite element analysis studies were performed to validate
the finite element model of the femoral neck and intertrochanteric fractures.
In simulation A, Sawbone (model #3403) with Ø6.5 mm non-cannulated screws were used.
Osteoporotic material properties were applied to the cancellous and cortical bone. A two
fragments of the femoral neck fracture were created based on the Pauwel’s classification angle
of 60° and progressive axial loading was applied to the femoral head until failure. The
maximum vertical reaction force and axial stiffness were 654.67 N and 621.2 N/mm
respectively.
In simulation B, Sawbone (model #3403) with proximal femoral nail anti-rotation (PFNA) was
used. Both osteoporotic and non-osteoporotic material properties were applied to the
cancellous and cortical bone. A four fragments of intertrochanteric fracture were created based
on the AO classification 31A2.2 and progressive axial loading was applied to the femoral head.
The axial stiffness for osteoporotic femur with medial fragment at the baseline was
877.2 N/mm, which is in a good agreement with published literature. From the baseline of the
medial fragment, a distal extension of 40 mm, 80 mm and 120 mm were created. Only the axial
stiffness of the 40 mm distal extension were found to be significantly lower than the baseline
