The development of a test for fibular reduction after syndesmosis injury - a cadaveric study

R. Boyd, F. Bintcliffe

Introduction: Injury to the syndesmosis is not always clearly demonstrated on radiographs and different tests have been described to assess for injury. In the presence of a significant injury to the syndesmosis, surgical fixation is often indicated and various fixation methods have been described. If the result of surgery is any mal-reduction of the fibula, this may result in ongoing ankle pain. Assessing how well the fibula has been reduced intra-operatively is currently limited to image intensifier views. We have previously developed a simple assessment, which has been shown to give accurate intra-operative demonstration of an injury to the syndesmosis. Our objective was to ascertain if the same test could demonstrate any malreduction of the fibular after repair of a syndesmosis injury.

Methods: Seven fresh frozen cadavers had complete sydesmosis disruption performed before fixation using a well-recognised technique with a single 3.5 mm small fragment screw. Purposeful malreduction was performed in three ankles and standard reduction in the remaining four. 2-5mls of contrast medium was then injected into the ankle joint.

Results: When there had been a malreduction, an obvious 'blush' of dye leaked superiorly into the surrounding soft tissues, whereas a normal ankle arthrogram was shown when the fibular had been anatomically reduced into the incisura and well fixed.

Conclusion: This cadaveric study showed the test to be an easy and reliable adjuct to assess for acute malreduction of a syndesmosis injury.