OBJECTIVETo evaluate the indications, surgical techniques and clinical effects of the fixation of posterior malleolus in complicated external rotation ankle fractures and illuminate the importance of anatomical reduction and rigid internal fixation of posterior malleolar fracture.

METHODSFrom July 2007 to June 2009, 32 patients were treated with open reduction and internal fixation,involving 21 males and 11 females with an average age of 36 years old (ranged from 19 to 68 years old). According to Lauge-Hansen classification: 13 cases of pronation-external rotation type (IV), 7 and 12 cases of supination-external rotation type (III and IV). Postoperative functional exercise and regular follow-up were done and outcomes were assessed.

RESULTSAll the patients were followed up,and the duration ranged from 7 to 20 months,with an average of 14.5 months. According to Ankle Hindfoot Clinical Rating System of the American Orthopaedic Foot & Ankle Society (AOFAS), 23 patients got an excellent result, 7 good, 2 fair, 0 poor.

CONCLUSIONAnatomical reduction and rigid internal fixation of posterior malleolar fracture as well as early functional exercise have significance in restoring ankle joint function and reducing the incidence of traumatic arthritis.