Operative Treatment of Nonunion Following Distal Fibula and Medial Malleolar Ankle Fractures

Background: The purpose of this study was to evaluate the outcomes following operative treatment of nonunited rotational distal fibula and medial malleolar ankle fractures. Methods: Seventeen patients were identified as having a nonunion of a rotational ankle fracture. All patients were evaluated clinically, radiographically, and functionally with the Short Musculoskeletal Functional Assessment (SMFA) questionnaire. They were divided into lateral and medial malleolus groups and compared with 44 patients following a nonoperative (SE2/3) ankle fracture and 25 patients who underwent operative fixation of their SE4 ankle fracture for functional comparison. Results: Two of the 17 patients were excluded. The patients in the medial malleolar group were notably older than those in the other groups. Nonunions included 12 distal fibulas and 3 medial malleoli. All patients were treated with open reduction with plate and screw fixation or screw fixation alone. Adjunctive grafting was performed in all but 2 cases. The average time to healing was 5.2 months post surgery. At latest follow-up, mean 33.9 months, all nonunions had resolved. Standardized SMFA scores differed notably among the groups in the Bothersome, Emotional, and Mobility categories. There was no difference between lateral malleolar nonunion patients and surgically treated SE4 patients. Conclusions: Reports of nonunions of fractures of lateral and medial malleoli have been rarely reported. Operative treatment of these nonunions in this study led to reliable bony healing. Patients who underwent surgery for these nonunions ultimately had similar outcomes and range of motion compared with patients who underwent operative treatment for acute ankle fractures. Level of Evidence: Level III, retrospective comparative series.