Direct anterior approach versus posterolateral approach in total hip arthroplasty: a meta-analysis of results on early post-operative period

BACKGROUND: This study was performed to compare the advantage and disadvantage of posterolateral approach (PLA) and direct anterior approach (DAA) in total hip arthroplasty (THA). METHODS: Relevant trials were identified via a search of the Cochrane Central Register of Controlled Trials and PubMed from inception to 1 June 2019. A meta-analysis was performed to compare postoperative perioperative and radiographic outcomes between DAA and PLA in THA with respect to the hospital stay, blood loss, incision length, operative time, complications, and femoral and cup component position. The Harris Hip Score (HHS) was also assessed before and after 6 months postoperatively. RESULTS: Nine eligible studies involving 22698 adult patients (DAA group, n = 2947; PLA group, n = 19751) were identified for analysis. Compared with the PLA group, the DAA group had shorter hospital stay and achieved better HHS within 6 months after operation (P < 0.05), but the HHS was no significant differences between the two groups over 6 months (P > 0.05). The DAA group had significantly longer operative time, more blood loss, and complications than the PLA group (P < 0.05). In addition, the femoral component positioned in neutral and cup component inclination angle was comparable between both groups (P > 0.05); however, cup component anteversion angle was significantly larger in the PLA group (P < 0.05). CONCLUSION: Patients in the DAA group had higher HHS within 6 months and shorter hospital stay. The DAA could offer rapid early functional recovery after THA compared with the PLA. However, the DAA group often required longer operative time and had more blood loss. Furthermore, there was a higher early complication rate. Therefore, we believe that the direct anterior approach was a more difficult technique. The surgeon should be a well-trained joint surgeon with extensive prior hip replacement experience before performing THA through a DAA, and DAA was not suitable for beginners performing THA. In addition, we did not observe the difference with regard to the femoral component position and cup component inclination angle except for the smaller cup component anteversion angle in DAA group.