Reproducible and Reliable Method for Syndesmotic Screw Fixation: An MRI-Based Cross-Sectional Image Analysis

Abstract

Ankle arthrosis may be an unexpected potential result in syndesmotic injuries because of instability and malreduction. For anatomical reduction and stabilization, a reliable and stable reference point is crucial to correctly place syndesmotic screw. The aim of this study was to determine a reliable reference point and to quantify the ideal angle for placement of the screw. In this prospective cohort study, 99 healthy volunteers underwent right ankle magnetic resonance (MR) imaging. On the axial sections, the ideal axis of the syndesmotic screw and other reference points were depicted with 4 lines and 2 angles which were evaluated at the level 2 cm above the tibial plafond. Values were recorded by 2 independent observers to assess for interobserver reliability. The mean value of syndesmotic screw position according to the ground line was 28° ± 6.4° like Arbeitsgemeinschaft für Osteosynthesefragen suggestion. Furthermore, it was determined that the syndesmotic screw could be placed more precisely in the position when placed at an angle of 26.2° ± 1.1° with the axis perpendicular to the line passing through the anterior tibial and Achilles tendons. Ideal syndesmotic screw positioning must be stable enough in case not to be affected by lower extremity alignment deficiencies or foot deformities. So, the anterior tibial and Achilles tendons can be used as reproducible and reliable landmarks for the placement of syndesmotic screws.