Volumetric measurement to diagnose syndesmotic injury in Danis-Weber B type ankle fractures / 国际外科学杂志

ABSTRACT

Objective:To investigate the change of syndesmotic volume via CT scan in Danis-Weber B type ankle fracture, aiming to provide a non-invasive diagnostic method for Danis-Weber B type ankle fracture combined with syndesmotic injury.Methods:Retrospective analysis was performed on 48 patients with Danis-Weber B type ankle fractures in Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2018 to March 2022, including 30 males and 18 females, aging (43.71±19.41) years. Ankle CT scans and three-dimensional reconstructions were performed before surgery and at the last follow-up, measuring the syndesmotic volume between the tibiotalar joint and 1, 3 and 5 cm above the ankle and compared with each other. Intraoperative exploration was used as the gold standard for the syndesmotic injury. Based on the results of exploration of the syndesmotic injury, patients were divided into simple ankle fracture group (fracture group, 25 cases) and ankle fracture combined with syndesmotic injury group (fracture + ligament group, 23 cases). The sensitivity and specificity of this diagnostic method were statistically evaluated. The assessments at the last follow-up were performed to value the clinical effect of surgery. The metric data conforming to the normal distribution were expressed as mean ± standard deviation ( ± s), and the t-tests were used for comparison between groups. The measurement data of skewed distribution were expressed as quartile M( Q1, Q3), and nonparametric tests were used for intergroup comparison. Counting data were expressed as number of cases and percentage (%), and Chi-square test were used for intergroup comparison. Results:In the fracture group, there were no statistically significant differences of the syndesmotic volume at 1, 3, and 5 cm above the ankle joint before surgery and at the last follow-up ( P=0.219, 0.269, 0.103). On the contrary, the volume above were statistically significant in the fracture + ligament group ( P<0.001). There were statistically significant differences in syndesmotic volume between the two groups at 1, 3, and 5 cm above the ankle joint preoperatively ( P=0.005, 0.004, 0.038). By contrast, there were no statistical differences between the two groups postoperatively ( P=0.082, 0.155, 0.249). For the sensitivity and specificity of Danis-Weber B type ankle fractures combined with syndesmotic injury, they were 92% and 67% at 1 cm above the ankle joint, 69% and 87% at 3 cm above the ankle joint, and 62% and 87% at 5 cm above the ankle joint, respectively. The last follow-up clinical function score indicated a good surgical outcome. Conclusions:Volumetric measurement via CT scan is one of the diagnostic methods for evaluating Danis-Weber B type ankle fracture combined with syndesmotic injurys. Open resection internal fixation combined with elastic fixation of the ankle fracture combined with syndesmotic injurys can significantly reduce the lower tibiofibular volume, and the efficacy is definite.