Biomechanical Aspects of Locking Reconstruction Plate Positioning in Osteosynthesis of Transverse Clavicle Fracture

Abstract

UNLABELLED: The aim of this study was to evaluate and compare the biomechanical effects of locking reconstruction plate positioning on the osteosynthesis of clavicle midshaft simulated transverse fractures. MATERIAL AND METHODS: Twelve synthetic clavicles with simulated midshaft transverse fractures were repaired with a 3.5-mm locking reconstruction plate in the anteroinferior or the superior position. The clavicles were randomly assigned to 2 groups (6 per group). Each repaired clavicle was tested in cantilever bending by using the universal testing machine. The maximal load and the displacement of the specimens at a load of 40 N were recorded for each group. RESULTS: The anteroinferior plating osteosynthesis with a 3.5-mm locking reconstruction plate could bear an average maximal load of 183.3 N (SD, 11.3); the corresponding load for the superior plating osteosynthesis with the identical implants was 444.8 N (SD, 102.3), and the mean displacement was 1.5 mm (SD, 0.5) and 0.7 mm (SD, 0.2), respectively. CONCLUSIONS: The superior plating osteosynthesis of simulated midshaft transverse clavicle fractures with the 7-hole 3.5-mm locking reconstruction plate had a significantly higher bending (from top to bottom) load to failure in comparison with the anteroinferior plating osteosynthesis of the clavicle with the identical implants. Clavicles plated with the 7-hole 3.5-mm locking reconstruction plate at the superior aspect exhibited a significantly greater biomechanical stability at a load of 40 N than those plated at the anteroinferior aspect.