Comparison of Different Fixation Confi gurations in Different Types of High Pediatric Supracondylar Humerus Fractures: a Finite Element Analysis.

ABSTRACT

PURPOSE OF THE STUDY The purpose of this study is to compare the stability of different fi xation methods in high pediatric supracondylar humerus fractures with a fi nite element analysis method. MATERIAL AND METHODS Transverse, lateral oblique, and medial oblique fracture models were created in a ten years old boy's distal humerus. Eight different fi xation methods were applied to each fracture model. Displacement of the fracture models was measured under the translational and torsional forces. RESULTS In the transverse fracture model; the 6th method provided the best stability in internal rotation, external rotation, and extension loading. In varus 7th method, valgus 8th, and fl exion the 5th and 2nd methods had the best stability. In the lateral oblique fracture model; the 7th method had the best stability in all loading directions except fl exion and the 6th method had the best stability in fl exion and had acceptable values in all other directions except valgus and external rotation. In the medial oblique fracture model; the 6th method had the best stability in all directions except varus. 3rd method was the best fi xation type against varus and the second stable fi xation type in all other directions. CONCLUSIONS Combining lateral antegrade with lateral retrograde wire and lateral condylomedullary wire provides strong stability in the lateral oblique fracture. Two condylomedullary Kirchner wires and one antegrade lateral wire results in a strong stability in the medial oblique fracture. Medial-lateral condylomedullary and lateral antegrade wires provided the best stability against varus in transverse and lateral oblique fractures. KEY WORDS high pediatric supracondylar humerus fracture, percutaneous fi xation method, metaphyseal-diaphyseal junction, fi nite element analysis.