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Our hypothesis was that there would be no obvious differences in mortality rates, functional outcomes and complications between the two groups. We therefore conducted a meta-analysis to compare the relative advantages of intramedullary nail and extramedullary fixation. A total of 10 randomized controlled trials including only patients with unstable intertrochanteric fractures were included in the final analysis. We found that no statistically significant difference in one-year mortality was observed between the two groups (RR: 0.78, 95% CI: 0.55\u20131.10, p\u2009=\u20090.160). Analysis of exact <jats:italic>p<\/jats:italic> values from five included studies indicated that functional outcomes were markedly better for patients of the intramedullary nail group when compared with those of the extramedullary fixation group (<jats:italic>p<\/jats:italic>\u2009=\u20090.0028), although evidence remains controversial. Higher incidences of all complications were noted for extramedullary fixation (RR:1.48, 95% CI: 1.12\u20131.96, <jats:italic>p<\/jats:italic>\u2009=\u20090.006). However, no significant differences in implant-related complications were observed between the two groups (RR:1.20, 95% CI: 0.73\u20131.97, <jats:italic>p<\/jats:italic>\u2009=\u20090.475). Therefore, comparing with extramedullary fixation, the intramedullary nail method would be more reliable and should be encouraging for unstable intertrochanteric fractures.<\/jats:p>","DOI":"10.1038\/s41598-018-20717-2","type":"journal-article","created":{"date-parts":[[2018,1,29]],"date-time":"2018-01-29T16:39:47Z","timestamp":1517243987000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["Comparing the Intramedullary Nail and Extramedullary Fixation in Treatment of Unstable Intertrochanteric Fractures"],"prefix":"10.1038","volume":"8","author":[{"given":"Wen-Qiang","family":"Zhang","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Sun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chun-Yu","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong-Yao","family":"Zhao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi-Feng","family":"Sun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2018,2,2]]},"reference":[{"key":"20717_CR1","doi-asserted-by":"publisher","first-page":"789","DOI":"10.1007\/s00264-009-0826-x","volume":"34","author":"AS Sidhu","year":"2010","unstructured":"Sidhu, A. 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