Achieving Accuracy and Gap Balancing in Fully Autonomous Robotic-Assisted Total Knee Arthroplasty with Functional Alignment in Valgus Knee Deformity.

INTRODUCTION

The robotic-assisted total knee arthroplasty (RA-TKA) facilitates real-time intra-operative balance assessment and accurate component positioning customized to the patient's ligamentous behavior, enhancing procedural accuracy and precision. Preliminary findings suggest RA-TKA, using fully autonomous computed tomography based systems, such as Cuvis, result in better short-term outcomes and improved patient-reported outcome measures. Coronal plane alignment of the knee classification aids to decide pre-arthritic phenotype of the knee and soft tissue balance judgment.

MATERIALS AND

METHODS

This investigation was conducted as a retrospective matched-cohort observational study. We retrospectively analyzed a matched group of patients to compare RA TKA with functional alignment (n = 26) and mechanically aligned conventional-TKA (CM-TKA) (n = 24) in individuals with a valgus deformity Ranawat grade 1 and 2. The evaluation included radiographic assessments and PROMs over a 6-month period. The Western Ontario and McMaster University Osteoarthritis Index score and Oxford Knee Score (OKS) were used to determine the outcomes.

RESULTS

The RA TKA cohort showed faster recovery than CM TKA patients. The RA TKA cohort required less soft tissue releases (P = 0.010). At the 3-month follow-up, there was a substantial reduction in pain in the RA TKA cohort (19.73 ± 2.38 vs. 25.71 ± 3.96, P = 0.000). However, over 6 months, pain reduction was found to be similar in both groups (13.27 ± 1.99 vs. 13.21 ± 2.04, P = 0.281). The improvement in OKS in RA TKA cohort was significant at 3 months (33.96 ± 3.88 vs. 31.04 ± 2.79, P = 0.006) and at 6 months (39.77 ± 2.97 vs. 36.46 ± 3.18, P = 0.136), and improved ROM in both groups (111.25 ± 13.29 vs. 116.96 ± 9.31, P = 0.083), with improvement in flexion (12.73 ± 5.85 vs. 7.08 ± 10.41, P = 0.210) in RA TKA compared to the CM-TKA cohort.

CONCLUSION

The CUVIS robotic system leads to optimum gap balancing throughout the range of motion, less soft tissue release, less post-operative pain, and improved function in short-term follow-up with optimum patella tracking in valgus knees.