A propensity score-matched comparison between Mako robotic arm-assisted system and conventional technique in total hip arthroplasty for patients with osteoarthritis secondary to developmental dysplasia of the hip

Background The clinical effectiveness of robotic arm-assisted systems remains unclear for total hip arthroplasty (THA) in patients suffering from osteoarthritis secondary to developmental dysplasia of the hip (DDH). Methods Patients with DDH who underwent primary THA were included in this study. We conducted a propensity score-matched comparison between THAs using a robotic arm-assisted system (Mako group) versus those using the manual procedure (manual group) to compare the absolute differences in cup placement angles measured using postoperative computed tomography and those planned preoperatively. Results A total of 217 patients with osteoarthritis due to DDH met the inclusion criteria. Eighty-four patients were matched as the Mako group and 84 as the manual group. The differences were smaller in the Mako group than the manual group in terms of both inclination and anteversion angles (1.1 +/- 1.0 versus 4.2 +/- 3.1, respectively; 95% CI, 2.4 to 3.8; p < 0.0001, and 1.2 +/- 1.1 versus 5.8 +/- 4.0, respectively; 95% CI, 3.7 to 5.5; p < 0.0001). Conclusions The robotic arm-assisted system may provide more accurate cup placement in THA for DDH.