Reliability of Intraoperative Tests for Syndesmotic Disruption

Abstract

Background: Management of the distal tibiofibular syndesmosis remain controversial area in the treatment of ankle fractures. Objective was to evaluate reliability of intraoperative test for syndesmotic disruption including hook test and tap test and compare it with preoperative radiographs. Methods: The study include 20 patients. Results: The mean age of the studied patients was 36 years. Regarding gender, there was a male predominance; about two-thirds of the studied patients were males (60.0%). More than one-third of the studied patients were from rural areas (40.0%). Also, more than one-third (40.0%) were smokers. Syndesmotic disruption was detected in more than one-third of the patients (45.0%) by pre-operative radiographs. Hook test was positive in half of the patients (50.0%), while tap test was positive in all patients (100.0%). When comparing results of hook and tap tests to the reference pre-operative radiograph findings, hook test showed a sensitivity of 44.4%, specificity of 45.5%, PPV of 40.0%, NPV of 50.0%, and overall accuracy of 45%. Tap test showed a sensitivity of 100.0%, specificity of 0.0%, PPV of 45.0%, NPV of 0.0%, and overall accuracy of 45%. Conclusion: Tap test is better than hook test in detection of Syndesmotic disruption and matching with preoperative radiograph Tap test is a simple, accurate and reliable technique for detection of syndesmotic instability. Diagnostic indices of hook and tap tests demonstrated similar overall accuracy.