Trends in the Characterization of the Proximal Humerus in Biomechanical Studies: A Review

Abstract

Proximal humerus fractures are becoming more common due to the aging of the population, and more related scientific research is also emerging. Biomechanical studies attempt to optimize treatments, taking into consideration the factors involved, to obtain the best possible treatment scenario. To achieve this, the use of finite element analysis (FEA) is necessary, to experiment with situations that are difficult to replicate, and which are sometimes unethical. Furthermore, low costs and time requirements make FEA the perfect choice for biomechanical studies. Part of the complete process of an FEA involves three-dimensional (3D) bone modeling, mechanical properties assignment, and meshing the bone model to be analyzed. Due to the lack of standardization for bone modeling, properties assignment, and the meshing processes, this article aims to review the most widely used techniques to model the proximal humerus bone, according to its anatomy, for FEA. This study also seeks to understand the knowledge and bias behind mechanical properties assignment for bone, and the similarities/differences in mesh properties used in previous FEA studies of the proximal humerus. The best ways to achieve these processes, according to the evidence, will be analyzed and discussed, seeking to obtain the most accurate results for FEA simulations.

The biomechanical effect of fibular strut grafts on humeral surgical neck fractures with lateral wall comminution

“…The involvement of the greater tuberosity (GT) is known to be common with its incidence up to 20% among all types of proximal humerus fractures 11 . Furthermore, the fixation plate is commonly placed lateral wall of the GT 12 , 13 . Considering that proximal humeral fractures occur in the elderly, stability of fixation may be significantly compromised by lack of lateral wall integrity of the greater tuberosity, especially in cases of low bone mass in the humeral head 4 .…”

Optimization of Locking Plate Screw Angle Used to Treat 2-Part Proximal Humerus Fractures to Maintain Fracture Stability

“…To perform the analysis for the locking plate along with the 2part fracture of the proximal humerus, the following considerations were made: The screw models were simplified to a simple isotropic cylinder with a diameter of 2.9 mm resembling the inside diameter of 3.5 mm locking screws. Bone tissues were considered isotropic, with a modulus of elasticity (E) of 15.6 GPa and 0.47 GPa for the cortical and cancellous bone respectively, Poisson's ratio (v) = 0.3 (average taken from www.videleaf.com literature [28]). 316L stainless steel (E = 190 GPa [18] and v = 0.3) was assigned as the material of manufacture for all fixation elements.…”