Syndesmotic disruption in low fibular fractures associated with deltoid ligament injury.

Low fibular fractures that were associated with deltoid ligament disruption and inferior tibiofibular syndesmotic disruption were studied. All of the patients had a Type B Weber fibular fracture associated with a deltoid ligament injury. It was difficult to detect the syndesmosis disruption on the initial assessment of the anteroposterior and mortise radiographs obtained preoperatively because there was no obvious talar shift on the plain radiograph. Careful evaluation of the plain radiograph and determination of all the recommended measurements were necessary to diagnose the syndesmotic disruption. However, the syndesmotic disruption was easily recognizable on axial computed tomography scans when comparing the injured and the noninjured sides. Axial computed tomography scans also showed a shallow incisura fibularis in all patients and in three cases it revealed anterior fibular subluxation that was not appreciated on the plain radiographs obtained preoperatively. On the basis of the current study using the level of the fibular fracture as a guideline for application of the syndesmotic screw as suggested by some authors may not be accurate. There are several factors that should be considered including the depth of the incisura fibularis, posterior malleolus fractures, deltoid ligament injury, and subluxation of the fibula. The surgeon's impression in the operating room of syndesmosis stability should be considered as the best guideline in the application of syndesmosis fixation rather than depending on the level of the fibular fracture.