Does Robotic-Assisted Total Hip Arthroplasty Improve Accuracy of Cup Positioning?

Acetabular component malpositioning is a frequent cause of complications in total hip arthroplasty including instability, increased wear, osteolysis, impingement, and revision surgery. Recently, robotics and navigation have been introduced to improve cup positioning in total hip arthroplasty. The purpose of this study was to compare the accuracy of postoperative acetabular component positioning using MAKO robotic-assisted versus manual acetabular component placement. A consecutive series of 100 total hip replacements were performed in 100 patients. The first 50 were performed using manual techniques, while the second 50 were performed using MAKO-guided acetabular component placement. Postoperative anteroposterior pelvis radiographs were used to determine the postoperative anteversion and inclination of the cup relative to the goal of 15 and 45°, respectively. In the manual group, the average anteversion and inclination was 14.3 and 44.2°, respectively, with 28% within 5° and 82% within 10° of the goal alignment, respectively. In the robotic group, the average anteversion and inclination was 15.1 and 45.6°, respectively, with 54 and 88% within 5 and 10° of the goal alignment, respectively. This equated to a statistically significant improvement in the number of acetabular components placed within 5° of the target alignment with the use of robotic guidance ( p  = 0.0142). From the authors' study, they were able to demonstrate a significant improvement in acetabular component alignment with the use of robotic techniques. Additional studies are needed to demonstrate improvement in clinical outcomes as a result of improved accuracy and precision of acetabular component placement.