Evaluation of the plate location used in clavicle fractures during shoulder abduction and flexion movements: a finite element analysis

Plate fixation is a commonly used surgical method in clavicular fracture treatment. The main purpose of this treatment is making the painless shoulder girdle and bring the functions to the optimum level. Plate fixation position still remains controversial. We aimed to investigate the effect of the plate position in clavicle midshaft fractures during shoulder movements. Methods: A normal anatomical shoulder joint was modeled using computed tomography images. A fracture line was created on the clavicle. Plate was placed superior to the clavicle in group 1 and anterior in group 2. The impacts of joints, plates, screws, ligaments and clavicle have been shown during 150° flexion and abduction movements of the shoulder by finite element analysis. Analyzes were made non-linear using ANSYS (version 18) and the same boundary conditions were applied in all models. Results: The load values in the plate, screws, ligaments, and clavicle were higher in group 1 than group 2 during abduction and flexion movements. Especially the load on the ac ligament was excessive. Load value in the glenohumeral joint was found similar both groups. The load values in the flexion movement were higher than the abduction movement in both groups. Conclusions: Anterior clavicle plating provides less stress on material and shoulder girdle, compared to superior plating, during shoulder abduction and flexion movements.