Fig. 1

The search results and selection procedure. Seven hundred ninety-one relevant citations were identified from the databases according to the literature search strategy described earlier. After deleting 218 duplicates, we obtained 573 articles. Upon review of titles and abstracts of the 573 remaining articles, 502 irrelevant clinical studies were excluded. By reading the 71 full-text articles, we excluded another 64 articles for the following reasons such as (systematic) reviews, surgery techniques, none-compare groups, cadaver researches, animal researches, and no useful outcome data. The remaining seven articles were deemed appropriate. Finally, we identified 1417 patients (1481 hips) assessed in (2 RCTs [30, 31] and 5 nRCTs