BackgroundThe fixation methods of posterior malleolar fracture (PMF) in trimalleolar ankle fractures is still controversial. We aim to compare clinical and radiological outcomes between plate fixation and screws fixation for PMF in trimalleolar ankle fractures. MethodsLiterature search was performed through PubMed, EMBASE, Cochrane Library and CNKI database from databases inception to May 2022 to identify randomized controlled trial (RCT) and comparative clinical study in English or Chinese. A meta-analysis was performed using RevMan 5.1 software, and systematic review was performed when the data extracted from included studies could not be synthesized. ResultsTwo RCTs and six cohort studies were included. The meta-analysis results showed that articular step-off or gap in plate fixation was superior to antero-posterior screws fixation (RR = 0.28; 95%CI: 0.11, 0.76; P = 0.01). there were no significant differences in American Orthopaedic Foot & Ankle Society scores (MD = -0.19; 95%CI: -2.43, 2.05; P = 0.87), arthritis (RR = 1.67; 95%CI: 0.61, 4.55; P = 0.32), infection and total complication (RR = 1.42; 95%CI: 0.89, 2.25; P = 0.14). ConclusionPlate fixation might have better articular step-off or gap, compared with “A to P” screws fixation for the posterior malleolus in trimalleolar ankle fractures. Screw fixation could achieve shorter surgical time than plate fixation. However, no significant differences were found in AOFAS scores, arthritis, infection, sural nerve injury and total complication during the comparisons.