ObjectiveTo investigate the efficacy of total hip arthroplasty (THA) assisted by the MAKO robotic arm via posterolateral approach.MethodsThe clinical data of 70 patients treated with THA via posterolateral approach between March 2017 and March 2019 who met the selection criteria were retrospectively analyzed. According to different treatment methods, the patients were divided into two groups, 35 were treated with MAKO robotic arm assisted THA (MAKO group) and 35 with traditional THA (THA group). There was no significant difference in gender, age, body mass index, disease duration, etiology, perioperative time, preoperative activity of daily living (ADL) scale index, American Society of Anesthesiologists (ASA) classification, walking ability, comorbidities, hemoglobin, and other general data between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stay, postoperative acetabular abduction and anteversion angles, postoperative length difference of bilateral lower limbs, and proportions of intraoperative blood transfusion, immediate postoperative loading, wound drainage time more than 2 days, and complications were recorded and compared between the two groups. According to the X-ray films at 6 months after operation, the reduction quality was judged. The forgotten joint score, Harris score, and proportions of independent walking and ADL index increased were used to evaluate the function recovery of patients.ResultsPatients in both groups were followed up 6-18 months, with an average of 8 months. There was no significant difference (P>0.05) between the two groups in operation time, intraoperative blood loss, hospital stay, acetabular abduction and anteversion angles, and length difference of both lower limbs at 6 months after operation. There was no significant difference in the proportions of intraoperative blood transfusion, immediate postoperative loading, and wound drainage time more than 2 days between the two group (P>0.05). X-ray reexamination at 6 months after operation showed that there was no significant difference in the reduction quality between the two groups (Z=4.191, P=0.123). Postoperative complications occurred in 7 patients (20.0%) in the MAKO group and 10 patients (28.6%) in the THA group, showing no significant difference in the incidence of complications between the two groups (χ2=2.121, P=0.224). Two patients (5.7%) in the MAKO group and 4 patients (11.4%) in the THA group underwent revision within 6 months, showing no significant difference in the revision rate between the two groups (χ2=0.729, P=0.673). At 3 and 6 months after operation, the proportions of independent walking and ADL index increased showed no significant difference between the two groups (P>0.05). Harris scores in both groups improved significantly when compared with preoperative scores (P<0.05); there was no significant difference in the forgotten joint scores and Harris scores between the two groups (P>0.05).ConclusionCompared with traditional THA, MAKO robotic arm assisted THA has longer operation time and more intraoperative blood loss, but it has the advantages of accurate positioning and simple operation, and there is no significant difference in short-term postoperative function recovery.