RESUMO
Background: Ankle fracture-dislocations are one of the most severe types of ankle injuries. Compared to the simple ankle fractures, ankle fracture-dislocations are usually more severely traumatized and can cause worse functional outcomes. The purpose of this study was to review the previous literatures to understand the anatomy, mechanisms, treatment, and functional outcomes associated with ankle fracture-dislocations. Methods: The available literatures from January 1985 to December 2021 in three main medical databases were searched and analyzed. The detailed information was extracted for each article, such as researchers, age, gender, groups, type of study, type of center research, level of evidence, significant findings, study aim, cause of injury, time from injury to surgery, type of fracture, direction of dislocation, follow-up, postoperative complications and functional evaluation scores. Results: A total of 15 studies (1,089 patients) met the inclusion criteria. Only one study was a prospective randomized trial. The top-ranked cause of injury was high-energy injury (21.3%). Moreover, the most frequent type of fracture in ankle dislocations was supination-external rotation (SER) ankle fracture (43.8%), while the most common directions of dislocation were lateral (50%) and posterior (38.9%). Conclusions: Collectively, most ankle fracture-dislocations are caused by high-energy injuries and usually have poor functional outcomes. The mechanism of injury can be dissected by the ankle anatomy and Lauge-Hansen's classification. The treatment of ankle fracture-dislocations still requires more detailed and rational solutions due to the urgency of occurrence, the severity of injury, and the postoperative complications.
RESUMO
Supination external rotation (SER) type ankle fracture is the most common ankle fracture in the Lauge-Hansen classification and is often accompanied with syndesmotic injury. However, the mechanism of this injury is indistinct and a suggestive role can be given by preoperative imaging. This study was to preoperatively predict whether SER type ankle fractures are accompanied with syndesmotic injuries by the means of lateral malleolus fracture mapping. One hundred and forty-eight patients diagnosed with SER type ankle fractures were retrospectively enrolled in this study. The baseline data were collected and computed tomography data were reconstructed in 3-dimensional (3D) model. Patients were divided into stable and unstable groups according to intraoperative Cotton test and whether the inferior tibiofibular screw was placed. All fracture lines were superimposed on the ankle template to create a fracture map, and the data on the fracture map were further measured. Logistic regression was conducted to identify relevant factors and the cutoff values were given using receiver operating characteristic curves. Forty-one patients were enrolled in the unstable group and 107 patients were enrolled in the stable group. The lateral malleolus fracture lines of the unstable group were higher and steeper than that in the stable group on lateral and posterior views. The fracture height of the posterior cortex and peak height were the significant contributing factors, and the cut-off values of posterior cortex, peak height and inclination angle were 40.35 mm (sensitivity: 78%, specificity: 82%), 55.34 mm (sensitivity: 85%, specificity: 70%) and 55.6° (sensitivity: 66%, specificity: 86%), respectively. In general, when the fracture lines of the lateral malleolus were high and steep, it was usually indicative of a syndesmotic injury and can be predicted by the preoperative 3D reconstruction of fracture height of posterior cortex, peak height and inclination angle. If the cut-off values of these indicators are exceeded, the syndesmotic injuries may be presented and need to be verified in the intraoperative Cotton test to decide whether to insert an inferior tibiofibular screw.
