Imageless and image-based robotic-assisted total knee arthroplasty achieve equivalent radiographic accuracy: A randomised controlled trial.

Study Summary

95 patients with primary knee osteoarthritis were randomized to imageless robotic surgical assistant total knee arthroplasty (ROSA-TKA) or image-based ROSA-TKA. The primary outcome was radiographic accuracy, assessed by differences among final intraoperative planned measurements, robotic-validated measurements after bone cuts, and postoperative scanogram measurements for the hip-knee-ankle angle, femoral coronal and sagittal alignment, tibial coronal alignment, and tibial sagittal alignment. Secondary outcomes included registration time, the Knee injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS), and complications. Outcomes were assessed at 6 and 12 weeks. Overall, the results revealed equivalent radiographic accuracy between the two techniques, with differences between intraoperative planning and robotic validation of 1° or less across all parameters. Functional outcomes and registration times were also comparable, and no complications occurred, suggesting that workflow and resource considerations may guide technique selection rather than accuracy concerns.