Fig. 1.

The search results and selection procedure. Legend: The literature search identified 248 citations. Of these, 112 duplicates were removed. Upon review of titles and abstracts of the 136 remaining articles, we excluded 123 papers according to the inclusion criteria; the full text of 13 articles was retrieved. Because sufficient data were not available in one article, three studies were non-RCTs; hence, four studies were excluded. Finally, we identified 783 TKAs (722 patients) assessed in 9 randomized controlled trials