Robotic-Assisted versus Manually Implanted Total Hip Arthroplasty: A Clinical and Radiographic Comparison

Component positioning during THA is one of the more critical surgeon-controlled factors as malposition has been associated with higher rates of hip dislocations, poor biomechanics, accelerated wear rates, leg length discrepancies (LLDs), and revision surgeries. In order to reduce the rates of component malposition and improve surgical accuracy, robotic-assisted THA has developed increased interest. The primary objective of this study was to compare patient outcomes following THA using the Mako Stryker robotic system (Stryker Orthopaedics, Mahwah, New Jersey) to outcomes in patients who underwent conventional instrumented THA.

Consecutive patients undergoing THA with a direct-lateral surgical approach from a single surgeon were reviewed. Patients were treated with either a robotic-arm assisted total hip arthroplasty (RTHA) or a conventional-instrumented total hip arthroplasty (CTHA). Minimum follow up was 16 months.

Robotic-assisted THA significantly improved patient outcomes compared to conventional THA. No significant differences were observed in postoperative radiographic outcomes between the RTHA and CTHA cohorts. In our analysis, patients in the RTHA cohort compared to the CTHA cohort had significantly higher Western Ontario and McMaster Universities Arthritis Index (WOMAC) (P<0.001) and Harris Hip Scores (P<0.05) at final follow up. There were no significant differences between the RTHA cohort and CTHA cohorts in regard to cup inclination (°) (P=0.10), hip length difference (mm) (P=0.80), hip length discrepancy (mm) (P=0.10), and global offset difference (mm) (P=0.20).

Further studies, particularly prospective randomized studies, are necessary to investigate the short- and long-term clinical outcomes, possible long-term complications, and cost-effectiveness of robotic-assisted THA in regard to improving outcomes and accuracy.