Biomechanical Evaluation of Different Fixation Methods for Tibial Eminence Fractures

Abstract

Background Tibial eminence fractures have become more common, but the best method of fixing these fractures arthroscopically has not been elucidated. Objective The objective of this study is to assess the stability of different fixation methods for tibial eminence fractures. Study Design Controlled laboratory study. Methods The authors evaluated the initial fixation strength of 4 different fixation techniques for tibial eminence fractures (2 screws, 1 screw, suture fixation with 1 mm Ethibond, and suture fixation with No. 5 FiberWire) using single cycle and cyclic loading tests. The tests were performed by loading the knee with an anterior tibial shear force. Results Suture cerclage with the FiberWire showed significantly higher maximum load (599.6 N) and stiffness (36.99 N/mm) than all other fixation methods tested. The lowest maximum load in the single cycle loading test was observed in the group with 2 screws (1 screw, 371.2 N; 2 screws, 249.8 N). The lowest stiffness was found in the Ethibond group (14.5 N/mm). After 1000 cycles of loading, the maximum load of the FiberWire fixation was significantly higher than the maximum load of the Ethibond fixation (399.4 N), the fixation with 1 screw (354.2 N), and the fixation with 2 screws (301.5 N). Conclusion These biomechanical data suggest that under cyclic loading conditions, suture fixation of tibial eminence fractures provides more fixation strength than screw fixation. Clinical Relevance A second screw has no positive effect on the biomechanical characteristics of screw fixation.