Robotic-assisted unicompartmental knee arthroplasty is associated with earlier discharge from physiotherapy and reduced length-of-stay compared to conventional navigated techniques

Introduction Computer-assisted surgery (CAS) has been used to improve intraoperative accuracy to restore patient's anatomy and joint kinematics. It is not yet known whether robotic systems provide significant benefits over established navigation techniques. Materials and methods Thirty-one patients underwent robotic-assisted UKA (RA-UKA) over a 14-month period. Length of operation, transfusion requirements, time to discharge, range-of-motion and analgesia requirements were compared to a similar cohort of 31 patients who had received UKA using computer-assisted surgery (CAS-UKA). Results All patients in the RA-UKA and CAS-UKA groups underwent surgery without conversion to conventional techniques. Both cohorts were similar apart from mean BMI (RA-UKA-group 28.5 vs 32.2; p < 0.05). There was a higher percentage of females in the CAS-UKA group (68% vs 45%, p = 0.12). Minor complication rates were the same in both groups (4/31, 12.9%). Mean operating time was longer in the RA-UKA group (104.8 vs 85.6 min; p < 0.001). No patients required post-operative transfusion in either group and there was no significant difference in haemoglobin level drop or analgesia requirements at any time point. Patients in the RA-UKA group achieved straight leg raise without lag sooner (23 vs 37.5 h; p = 0.004) and demonstrated increased range-of-motion on discharge (81.4 degrees vs 64.5 degrees; p < 0.001). Patients in the RA-UKA group were discharged from physiotherapy services earlier than the CAS-UKA group (42.5 vs 49 h; p = 0.02) and discharged from hospital significantly sooner (46 vs 74 h; p = 0.005). Conclusions RA-UKA is safe and reproducible, comparable to traditional navigation. Patients undergoing RA-UKA achieve straight leg raise and discharge from physiotherapy sooner than with navigation alone.