Biomechanical Analysis of Crossed Pinning Construct in Supracondylar Fracture of Humerus: Does the Point of Crossing Matter?

Abstract

Introduction This appears to be the first biomechanical study that compares the stability of various locations of the crossing points in crossed pinning Kirschner wiring (K-wire) construct in treating pediatric supracondylar humerus fracture (SCHF). Additionally, this study compared the biomechanical stability between crossed pinning K-wire construct and the three-lateral divergent K-wire construct. Methods For the study purpose, 30 synthetic humerus bones were osteotomised at mid-olecranon fossa, anatomically reduced, and pinned using two 1.6-millimeter K-wires in five different constructs. A total of six samples were prepared for each construct and tested for extension, flexion, valgus, varus, internal rotation, and external rotation forces. Results As for crossed pinning K-wire construct, the center crossing point emerged as the stiffest construct in both linear and rotational forces, in comparison to the lateral crossing point, superior crossing, and medial crossing point Conclusion Based on this analysis, it is highly recommended that, if the crossed pinning construct is selected to treat supracondylar humerus fracture, the surgeon should aim for center crossing point as it is the most stable construct. Nevertheless, if lateral and superior crossing points are obtained during the initial attempt of fixation, the fixation may be accepted without revising the K-wire as the stability of these two constructs are comparable and portrayed no significant difference when compared to that of the center crossing point. Additionally, it is essential to avoid the medial crossing point as it is significantly less stable in terms of rotational force when compared to the center crossing point.