Periprosthetic femoral fracture fixation: a biomechanical comparison between proximal locking screws and cables.

Background: The incidence of periprosthetic femoral fractures (PFF) around a stable stem is increasing. The aim of this biomechanical study was to examine how three different methods of fixation, for Vancouver type B1 PFF, alter the stiffness and strain of a construct under various configurations, in order to gain a better insight into the optimal fixation method.

Methods: Three different combinations of proximal screws and Dall-Miles cables were used: (A) proximal unicortical locking screws alone; (B) proximal cables and unicortical locking screws; (C) proximal cable alone, each in combination with distal bicortical locking screws, to fix a stainless steel locking compression plate to five synthetic femora with simulated Vancouver type B1 PFFs.

Periprosthetic femoral fracture--a biomechanical comparison between Vancouver type B1 and B2 fixation methods.

Current clinical data suggest a higher failure rate for internal fixation in Vancouver type B1 periprosthetic femoral fracture (PFF) fixations compared to long stem revision in B2 fractures. The aim of this study was to compare the biomechanical performance of several fixations in the aforementioned fractures. Finite element models of B1 and B2 fixations, previously corroborated against in vitro experimental models, were compared.

The effect of fracture stability on the performance of locking plate fixation in periprosthetic femoral fractures.

Periprosthetic femoral fracture (PFF) fixation failures are still occurring. The effect of fracture stability and loading on PFF fixation has not been investigated and this is crucial for optimum management of PFF. Models of stable and unstable PPFs were developed and used to quantify the effect of fracture stability and loading in a single locking plate fixation.

Evaluation of a new approach for modelling the screw-bone interface in a locking plate fixation: a corroboration study.

Computational modelling of the screw-bone interface in fracture fixation constructs is challenging. While incorporating screw threads would be a more realistic representation of the physics, this approach can be computationally expensive. Several studies have instead suppressed the threads and modelled the screw shaft with fixed conditions assumed at the screw-bone interface.