Reduction Quality in Posterior Malleolar Fractures using the Modified Posteromedial Ankle Approach

Abstract

Category: Trauma; Ankle Introduction/Purpose: Several studies have documented which of the posterior ankle approaches has the best exposure of the posterior malleolus. However, no study has made a correlation between the quality of posterior fragment reduction using CT scan and the approach used. The purpose of this study was to assess the quality of reduction of posterior malleolus fractures in patients with trimalleolar ankle fractures operated with the modified posteromedial approach. Methods: A retrospective search was performed in two Health Centers between 2014 and 2021 for patients with ankle fracture dislocations associated with types two, three and four PM fractures according to the Bartonicek classification3. In relation with the inclusion criteria, patients included in the study had complete trauma ankle set radiographs and CT scans with axial, sagittal and coronal planes pre and postoperative and in all of them a direct reduction and internal fixation of the posterior malleolus was achieved with the modified posteromedial approach. All procedures were performed by six experienced Foot and Ankle Surgeons. 48 patients met the inclusion criteria (29 women and 19 men) with a mean age of 46 years (range 23-80). 6 patients required two stage management with an initial external fixation because of irreducible fracture-dislocations or soft tissue compromise and in a second time the final ORIF. Results: Axial CT Plane Evaluation Evaluation of the morphology of the fractured PM according to the Bartonicek classification on the CT scan axial planes showed type II in 11 patients, type III in 31 patients and type IV in 7 patients. In relation to fibular position at the fibular notch 39 patients showed adequate reduction. Four patients showed diastasis or GAP >= 2mm as a consequence of intercalary fragment unreduced. Sagittal CT Plane Evaluation Sagittal CT plane evaluation showed anatomical reduction (<2mm) in 45 patients and poor reduction in 3 patients. Fourteen patients showed residual impaction either in posteromedial (type III fractures) or posterolateral fragments (type II, III or IV fractures). Conclusion: In conclusion, we think the modified posteromedial approach is a good option to manage trimalleolar fractures, since we achieved an anatomic posterior malleolus fracture reduction in 94% of our patients.