Cadaveric biomechanical assessment of different configurations for a novel pin and plate fixation method in distal humerus fractures

Abstract

Use of dual pre-contoured plates has been accepted as the treatment of choice in distal humerus fractures despite challenges especially in very distal or highly fragmented fractures. Aiming to improve results in such instances, our newly proposed method uses several K-wires fixated by a small reconstruction plate. Drawing on the results of previous finite element studies, the current study aims to compare the stiffness of three clinically common variations of this method using biomechanical testing in cadaveric humeri. 24 samples were divided into three groups and fractures were simulated. Groups I and II used 1.5 mm K-wires in differing configurations while 2 mm wires were used in group III. All samples underwent compression, anterior and posterior bending, and torsional testing as well as failure testing. Our results indicated that Group III had significantly higher stiffness in flexion, extension, and torsion (p < 0.05). In failure, group III had the highest mean stiffness in anterior bending and torsion (861.2 N, 30.9 Nm). Based on previous and current results, this new Persian fixation method, especially when implemented using 2 mm K-wires, shows promise in achieving suitable stability and may be useful as an alternative approach in complex distal humerus fractures.