Dual plate has better biomechanical stability than hook plate or superior single plate for the fixation of unstable distal clavicle fractures: a finite element analysis.

Abstract

A variety of surgical techniques have been addressed for distal clavicle fractures, while none of these is considered to be gold standard fixation. Currently, dual plate fixation has been proposed and achieved satisfying clinical results. However, the biomechanical study about dual plate technique in treating unstable distal clavicle fractures is limited. Thus, the purpose of this study was to investigate the biomechanical properties of this technique by finite element analysis. A geometry model of distal clavicle fractures was combined with hook plate, superior single plate and dual plate, respectively, to simulate the implant fixation process. Two loading conditions and two boundary conditions were applied in the finite element models following a mesh convergence test. The stress distribution was observed, and peak von Mises stress and maximum displacement were used as indexes for analysis. The dual plate model showed the highest clavicle stress (13.1MPa), but lowest fixation stress (18.9MPa) compared to the hook plate and superior single model. In regarded to stability, dual plate model exhibited a minimum displacement with only 0.099mm. Dual plate fixation has better biomechanical stability with lower risk of implant failure. Thus, dual plate fixation is an alternative technique for unstable distal clavicle fracture. The complication of peri-implant fracture of dual plate technique should also be cautious in clinical practice, and more clinical evidence is needed.