Biomechanical evaluation of naviculocuneiform fixation with lag screw and locking plates

Background: There have been no biomechanical evaluations of naviculocuneiform (NC) joint fixation. This study compared biomechanically 3 different fixation constructs for NC-1-3 joint fixation. Methods: The present study compared the three fixation constructs lag screw with locking plate for each NC joint, two crossed lag screws for each NC joint and a separate lag screw for each NC joint with bridging locking plates. NC-1-3 fixation was performed stepwise, and rotation of each joint was evaluated after the application of each lag screw or locking plate and their removal. Results: All examined fixation techniques led to a significant reduced rotation of the NC joints. For NC-1 rotation decreased from 2.8 degrees (Range 1.2-6.6 degrees) to 0.6 degrees (0.2-3.0 degrees) for lag screw and locking plate (p = 0.002) and from 5.0 degrees (1.7-9.8 degrees) to 1.0 degrees (0.1-3.6 degrees) for crossed lag screws (p = 0.002). For NC-2, locking plate constructs were better with 0.2 degrees (0.1-0.5 degrees) compared to crossed lag screw osteosynthesis with 0.9 degrees (0.2- 1.6 degrees) (p = 0.011). Conclusion: Each evaluated fixation technique led to a reduced NC joint rotation. The fixation of any NC joint had no relevant effect on the adjacent NC joints. The results might support surgeons treating NC joint disorders. (c) 2021 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.