Relative Strengths of Intramedullary K-Wire Techniques for Digital Deformities

Hammertoe deformity correction surgery is one of the most common procedures performed by foot and ankle surgeons. Recent foot and ankle medical literature presents conflicting opinions regarding the optimal intramedullary fixation device and techniques for use in digital deformity correction. There are a number of varying fixation constructs of intramedullary Kirschner wire fixation reported for proximal interphalangeal joint arthrodesis; however, there are no reports of relative loading strength of the fixations. In this study, 90 sawbone models were divided equally into 3 groups of different intramedullary Kirschner wire fixation techniques: Group A- single straight, Group B- single bent, Group C- double bent. Each fixation construct underwent controlled axial loading and failure points were observed. Results showed no significant difference in load failure from all 3 groups with mean maximum force of Group A = 20N, Group B = 19.1N, and Group C =17.5N. We conclude that all Kirschner wire fixation options for digital deformity correction, will provide similar resistance to sagittal plane axial loads.