Related Experiment Video
Updated: Aug 13, 2025
A Mouse Model of Ankle-Subtalar Complex Joint Instability
Published on: October 28, 2022
Diagnosis of subtle syndesmotic instability using conventional CT-imaging and axial force in different foot positions
Juan Chans-Veres1, Mercedes Vallejo1, Ahmed E Galhoum2
1University Hospital Virgen del Rocío, Seville, Spain.
Background:
Currently, there is no available method that can objectively and reliably detect subtle instability of the distal tibiofibular joint. The purpose of this study is to diagnose, using computerized axial tomography and an adjustable simulated loading device, subtle instability of the tibiofibular syndesmosis.
Methods:
Fifteen healthy individuals and 15 patients with clinical suspicion of subtle instability of the tibiofibular syndesmosis (total 60 ankles) were studied using an adjustable simulated loading device (ASLD). This device allows to perform bilateral ankle CT scans in two forced foot and ankle positions (30° of plantar flexion, 15° of inversion, 20° of internal rotation and 15° of dorsal flexion, 15° of eversion, 30° of external rotation). Axial load was applied simultaneously in a controlled manner (70% body weight). Measurements on the axial image of computed tomography were: syndesmotic area (SA), fibular rotation (FR), position of the fibula in the sagittal plane (FPS), depth of the incisura (ID), anterior direct difference (ADD), middle direct difference (MDD) and posterior direct difference (PDD).
Results:
Statistically significant differences were observed in the variable syndesmotic area between healthy (mean=-0.14, SD=4.33) and diseased (mean=16.82, SD=12.3)(p < 0.001). No statistically significant differences were found in the variables ADD, MDD, PDD, ID, FPS and FR.
Conclusions:
Measurement of syndesmotic area employing axial force and forced foot positions using the ASLD may be useful for the diagnosis of subtle tibiofibular syndesmosis instability.
