Observe a distância entre a linha de fratura e o comprimento da área de trabalho: análise bidimensional de elementos finitos em modelo de fixação extramedular

Abstract

Objective: To determine the ideal working area for a simple transverse fracture line treated with a bridge plate. Methods: A 2-D finite element analysis of a hypothetical femur was performed for the quan titative evaluation of a large-fragment titanium alloy locking plate based on the principle of relative stability in a case of a simple transverse diaphyseal fracture. Two simulations(one case of strain and another case of stress distribution) were analyzed in three unique situations according to the von Mises stress theory. Load distributions were observed when the bone was subjected to a single vertical load of 1,000 N.Results: The longer the length of the implant flexion, which coincided with the working areaof the plate, the greater the flexion of the implant. The highest concentrations of stress on the plate occurred in the region around the screws closest to the bone gap. The closer the screws to the fracture site, the greater the demands on the plate.Conclusion: When using a large-fragment titanium alloy locking plate to stabilize a simple transverse fracture based on the principle of relative stability (bridge plate), the distance between the proximal and distal screws closest to the fracture line must be long. The farther away this fixation is, the lower the stress on the plate and the greater the dissipation of force in the form of deflection.