ObjectiveTo evaluate the advantage of single posterolateral approach for exposing the fragments of lateral malleolus and posterior malleolus in treating bimalleolar and trimalleolar fractures. MethodsBetween January 2013 and June 2015, 47 patients with ankle fractures were treated. Of 47 cases, 16 were male and 31 were female with an average age of 47.7 years (range, 25-65 years); the locations were the left side in 21 cases and the right side in 26 cases. According to types system of Lauge-Hansen, 11 cases were rated as pronation-external rotation and 36 cases as supination-external rotation. There were 9 cases of bimalleolar fractures and 38 cases trimalleolar fractures. CT examination showed that posterior malleolus fracture involved more than 35% of the joint surface in 11 cases, and 9 cases had comminuted posterior malleolus fracture. Of 47 cases, 44 had fresh fractures with a mean disease course of 4 days (range, 8 hours to 7 days), and 3 had old fracture with the disease course of 43, 58, and 62 days respectively. Posterior malleolus fractures were fixed with T-type plates in 12 cases, one-third tubular plates in 10 cases, and cannulated screws in 25 cases. ResultsThe operation time was 60-100 minutes (mean, 80 minutes); the bleeding volume was 50-100 mL (mean, 72 mL). Primary healing of incision was obtained in all patients, and no postoperative complications of infection, cutaneous necrosis, deep venous thrombosis, and sural nerve injury occurred. The CT examinations after operation showed anatomical reduction of fractures. All patients were followed up from 12 to 20 months (mean, 16 months). No fixation failure or reduction loss was found at last follow-up. All patients could walk normally. The active dorsiflexion of the affected ankles was within 5° less than normal side in 43 cases (91.5%) and 5-10° less than normal side in 4 cases (8.5%). The passive dorsiflexion of the affected ankles was within 5° less than normal side in 44 cases (93.6%) and 5-10° less than normal side in 3 cases (6.4%). According to the Olerud-Molander scoring system, the results were excellent in 40 cases, good in 5 cases, and fair in 2 cases; and the excellent and good rate was 95.7% at last follow-up. ConclusionThe single posterolateral approach could simultaneously expose the fragments of lateral malleolus and posterior malleolus, with less complication of the incision, short operation time, and clear exposure of posterior malleolus. The surgery could be performed under direct vision. It especially is suitable for bimalleolar and trimalleolar fractures with lateral malleolus and posterior malleolus.