Normal Distal Tibiofibular Syndesmosis Assessment Using Postmortem Computed Tomography (PMCT)

Background: Distal tibiofibular syndesmotic injuries, often misdiagnosed, can lead to substantial morbidity. This study utilized postmortem computed tomography (PMCT) to define normal syndesmotic relationships in 131 subjects. Methods: Three parameters were measured: fibular rotation (FR), sagittal translation (ST), and incisura depth (ID). Results: Interobserver reliability was excellent for FR and ID but moderate for ST. Anatomical variability was wide, with FR ranging from -0.4 degrees to 16.6 degrees, ST from 0.33 mm to 3.49 mm, and ID from 1.89 mm to 6.05 mm. Side-to-side variability within subjects was minimal. Gender-specific differences were observed in ST, possibly due to size variations, highlighting the need for gender-specific diagnostic criteria. Conclusions: Although establishing universal reference values is challenging, using contralateral ankles for comparison can enhance diagnostic accuracy in syndesmotic injuries. This study, the first of its kind, offers valuable insights into normal distal tibiofibular syndesmotic relationships based on PMCT data. Future validation studies in patients with syndesmotic injuries can further improve diagnostic accuracy.