Introduction: A beneficial effect of minimally invasive surgery (MIS) in total joint replacement has been postulated, but to date it still remains to be proven. This study aimed at assessing what the common effects of MIS are in all clinical trials/studies.
Methods: Randomized controlled trials of MIS total joint replacement were searched online in Medline, EMBASE, CINAHL, and the Cochrane Library. Data on clinical endpoints were extracted in duplicate.
Results: The authors pooled data from 13 studies and found beneficial "MIS effects" for most endpoints. Blood loss, clinical scores, and incision length were significantly different from the standard procedure. The calculated MIS effect could be successfully validated using 3 independent data sets.
Conclusion: Our analysis provides strong evidence for an intrinsic "MIS effect" in total joint replacement. However, most effect sizes seem too small to have much clinical meaning.