In Silico Comparison of Two Kirschner Wire Arrangements for Stabilization of Femoral Capital Physeal Fractures

Abstract

Introduction: Proximal femoral physeal fractures are commonly stabilized with multiple, parallel Kirschner wires; however, Kirschner wire penetration of the articular surface can result in substantial coxofemoral pathology. The objective of this study was to compare the epiphyseal purchase afforded by a linear or triangular pattern of Kirschner wires for stabilizing femoral capital physeal fractures. Our hypothesis was that Kirschner wires placed in a triangular pattern would result in more epiphyseal purchase.

Materials and Methods: Computed tomography scans of the pelvic limbs of 16 skeletally immature dogs were obtained. Virtual femoral models were created. For each dog, the left or right femur was randomly selected for analysis. Separate linear and triangular arrangements of three virtual 1.6-mm Kirschner wires were centered on the thickest area of the proximal epiphysis. The length of each Kirschner wire within the proximal femoral epiphysis was measured.

Results: Kirschner wire placement in triangular and linear patterns resulted in a mean epiphyseal purchase for each pin of 8.4 and 8.0 mm, respectively. Overall pin purchase was greater in the triangular pattern than the linear pattern for 88% dogs (p = 0.005). The mean difference in overall pin purchase was 1.34 mm (p < 0.001).

Discussion/Conclusion: Use of a linear or triangular pattern of Kirschner wires for proximal femoral epiphyseal fracture stabilization resulted in a greater implant purchase within the epiphysis. The triangular pin pattern may reduce the risk of intra-articular implant placement by more closely centering the Kirschner wires within the thickest region of epiphyseal bone.

Acknowledgements: There was no proprietary interest for this project. Funded by the University of Florida’s Jeff and Jo Godwin Advanced Small Animal Surgical Training and Canine Gait Laboratory.

Publication History

Article published online:
16 September 2024