Intraoperative three-dimensional imaging in ankle syndesmotic reduction.

Abstract Background: Injuries of the distal syndesmosis in ankle fractures are traditionally treated with a temporary adjusting screw fixation. Conventional fluoroscopic and X-ray examinations cannot reliably diagnose malpositions of the fixed tibiofibular syndesmosis. Postoperative computer tomography allows a reliable control of the transfixed region.The aim of the retrospective single-study was to clarify whether an intraoperative 3D image intensifier examination can detect malpositions of the syndesmosis already intraoperatively and whether the examination has an influence on the postoperative revision rate. Methods: In 200 patients with tibiofibular syndesmosis injuries, an intraoperative 3D scan was performed after reduction of the distal tibiofibular syndesmosis and placement of the adjusting screw. Postoperative computer tomography of both ankle joints was performed in all patients. Results: 15% of all intraoperative 3D scans (30 patients) showed a finding requiring correction in the area of the ankle joint. In 7% of the cases, a malposition of the fibula in the tibial incisura requiring correction was found. Further corrections were necessary due to the extent and position of the osteosynthesis material (7%) and for the removal of joint bodies (1%). Postoperative computer tomographies of the ankle joints showed no deformities requiring revision. Conclusion: An intraoperative 3D scan allows a reliable assessment of the injured ankle region and reduces the postoperative revision rate. This makes a postoperative routine CT examination of the ankle joint dispensable.