Background: Posterior malleolus (PM) fractures have historically been classified according to the size of the fragment, to study the need for surgical fixation and to assess clinical outcomes. Recent research has suggested that the morphology of the PM fragment is of more relevance than its size. Objectives: This systematic review aims to determine if the size of the PM fragment influences clinical outcomes of trimalleolar fractures after surgical fixation, and if so, to find out which fracture type has the best outcomes. Methods: This systematic review will be conducted according to the PRISMA guidelines. A literature search will be conducted on the electronic databases of PubMed, Embase, Scopus and Ovid with a pre-determined search strategy. A manual bibliography search of included studies will also be done. Original articles in English that have relevant data on the outcomes of PM fractures and its morphology will be included. Data will be extracted from included studies and analysis carried out with the help of appropriate software.

The authors have declared no competing interest.

This study did not receive any funding

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This study involves only openly available human data, which can be obtained from: PubMed, Embase, Ovid, Scopus, Google Scholar

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