Injury of the Tibiofibular Syndesmosis: Value of MR Imaging for Diagnosis

To compare the use of magnetic resonance (MR) imaging with the use of arthroscopy for the diagnosis of tibiofibular syndesmotic injury.This study involved 58 patients who had ankle sprains or distal fibular fractures and underwent surgery. All patients were examined with MR imaging for diagnosis of tibiofibular syndesmotic injury. When MR imaging revealed ligament discontinuity (criterion 1) or either a wavy or curved ligament contour or nonvisualization of the ligament (criterion 2), the injury was considered to be a ligament disruption. After MR imaging, ankle arthroscopy was performed in all patients for a definitive diagnosis of ligament disruption.Arthroscopic findings showed anteroinferior tibiofibular ligament (AITFL) disruption in 28 patients and posteroinferior tibiofibular ligament (PITFL) disruption in five patients. When an MR imaging diagnosis was based on criterion 1 only, the diagnosis of AITFL disruption was made with a sensitivity of 100%, a specificity of 70%, and an accuracy of 84%, and the diagnosis of PITFL disruption was made with a sensitivity of 100%, a specificity of 94%, and an accuracy of 95%. When an MR imaging diagnosis was based on criteria 1 and 2, the diagnosis of AITFL disruption was made with a sensitivity of 100%, a specificity of 93%, and an accuracy of 97%, whereas the diagnosis of PITFL disruption was made with a sensitivity of 100%, a specificity of 100%, and an accuracy of 100%.MR imaging with use of both criteria is highly accurate for the diagnosis of tibiofibular syndesmotic disruption.