Abstract: Objective To investigate the clinical characteristics of posterior malleolar ankle fracture, and the selection of the surgical approach. Methods From January 2013 to September 2015, 83 cases of posterior malleolar fractures were retrospectively analyzed. Haraguchi typing was performed based on the three- dimensional CT. There were 54 cases with HaraguchiⅠ type, 16 cases with HaraguchiⅡ type, and 13 cases with HaraguchiⅢ type. The patients who were HaraguchiⅠ and Haraguchi Ⅲ types accepted the operation with posterolateral approach. The patients who were Haraguchi Ⅱtype and combined medial malleolus fracture accepted the operation with medial approach. The Haraguchi Ⅱ patients who were not combined medial malleolus fracture were used the medial paraachilles approach. Images of the ankle joint were filmed 2 weeks, 4 weeks, 12 weeks, 6 months and 12 months after the surgery. The healing time, complications and corresponding record outcome were determined by X-ray and clinical examination. At the last follow-up, ankle function and quality of life of patients were evaluated according to the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score and SF-36. Results Eighty-three patients were follow-up for 6-24 (mean 15.4± 6.2) months. The fractures healed on Xray. The average X-ray healing time was from 12 to 24 (mean 18.6±4.2) weeks. AOFAS score was 71 to 100 (mean 88.4±8.4) points. Sixty-seven cases were excellent, 14 cases were good, 2 cases were moderate, and good rate was 97.59%. SF-36 physiological score was 31.6-69.2 points(mean 48.4±4.8 points); SF-36 psychological score 28.6-64.5 points(mean 45.8± 3.5 points). Chronic ankle pain was complained by one patient. He was diagnosed traumatic arthritis, oral non- steroidal drugs was used to relief his ankle pain. One patient wound infected, and healed after treatment. No instrument failure and fracture displacement were found. Conclusion According to fracture morphology and clinical features after posterior malleolar ankle fracture, different surgical approaches are selected, which will be satisfied with the outcome.

Key words: ankle joint, posterior malleolar fracture, fracture fixation, internal, surgical approach, treatment outcome