Assessing Screw Length Impact on Bone Strain in Proximal Humerus Fracture Fixation Via Surrogate Modelling

• NCJ Number: 309623
• Author(s): Daniela Mini; Karen J. Reynolds; Mark Taylor
• Date Published: August 2024
• Length: 17 pages
• Grant Number(s): 2016-DN-BX-0144
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)
• Award: Facilitating Forensic Research in Multiple Fields Using a Unique Computed Tomography Dataset

Annotation

The authors of this paper report on a study in which they hypothesized that the adaptive neural network-based surrogate models can predict the variation of bone strain with the variation of a single implant parameter, in a more cost-effective manner than a pure finite element analysis; and they conclude that the ANN-based model accurately captured bone strains and they confirm that it has potential for use in more complex problems with more variables.

Abstract

A high failure rate is associated with fracture plates in proximal humerus fractures. The causes of failure remain unclear due to the complexity of the problem including the number and position of the screws, their length and orientation in the space. Finite element (FE) analysis has been used for the analysis of plating of proximal humeral fractures, but due to computational costs is unable to fully explore all potential screw combinations. Surrogate modelling is a viable solution, having the potential to significantly reduce the computational cost whilst requiring a moderate number of training sets. This study aimed to develop adaptive neural network (ANN)-based surrogate models to predict the strain in the humeral bone as a result of changing the length of the screws. The ANN models were trained using data from FE simulations of a single humerus, and after defining the best training sample size, multiple and single-output models were developed. The best performing ANN model was used to predict all the possible screw length configurations. The ANN predictions were compared with the FE results of unseen data, showing a good correlation (R2 = 0.99) and low levels of error (RMSE = 0.51%–1.83% strain). The ANN predictions of all possible screw length configurations showed that the screw that provided the medial support was the most influential on the predicted strain. Overall, the ANN-based surrogate model accurately captured bone strains and has the potential to be used for more complex problems with a larger number of variables. (Published Abstract Provided)