Anatomy of the tibial incisura as a risk factor for syndesmotic injury.

BACKGROUND: The study aims at comparing the bony anatomy of the syndesmosis in patients who sustained a high fibular fracture with syndesmosis disruption and that of the non-injured population. We hypothesised that there are certain anatomical features making the syndesmosis susceptible to injury. METHODS: The CT examinations of 75 patients who sustained a high fibular fracture with syndesmosis disruption and control group of 75 patients with unrelated foot problems were compared. The depth, fibular engagement and rotational orientation of the tibial incisura were analyzed. RESULTS: With the median values of the control group as cutoff there were 71% shallow, 71% disengaged and 77% retroverted syndesmoses in the injury group. The differences between the groups were statistically significant for every measure (P<.002 to P>.0001). CONCLUSIONS: Patients with a shallow, disengaged and retroverted bony configuration of the syndesmosis are overrepresented among patients with syndesmosis disruption.