Robot-assisted unicompartmental knee arthroplasty can reduce radiologic outliers compared to conventional techniques

Autoři: Kwan Kyu Park aff001;  Chang Dong Han aff001;  Ick-Hwan Yang aff001;  Woo-Suk Lee aff001;  Joo Hyung Han aff001;  Hyuck Min Kwon aff001
Působiště autorů: Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Korea aff001
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article



The aim of this study was to compare the clinical and radiologic outcomes of robot-assisted unicompartmental knee arthroplasty (UKA) to those of conventional UKA in Asian patients.


Fifty-five patients underwent robot-assisted UKA and 57 patients underwent conventional UKA were assessed in this study. Preoperative and postoperative range of motion (ROM), American Knee Society (AKS) score, Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC), and patellofemoral (PF) score values were compared between the two groups. The mechanical femorotibial angle (mFTA) and Kennedy zone were also measured. Coronal alignments of the femoral and tibial components and posterior slopes of the tibial component were compared. Additionally, polyethylene (PE) liner thicknesses were compared.


There was no significant difference between the two groups regarding postoperative ROM, AKS, WOMAC and PF score. Robot group showed fewer radiologic outliers in terms of mFTA and coronal alignment of tibial and femoral components (p = 0.022, 0.037, 0.003). The two groups showed significantly different PE liner thicknesses (8.4 ± 0.8 versus 8.8 ± 0.9, p = 0.035). Robot group was the only influencing factor for reducing radiologic outlier (postoperative mFTA) in multivariate model (odds ratio: 2.833, p = 0.037).


In this study, robot-assisted UKA had many advantages over conventional UKA, such as its ability to achieve precise implant insertion and reduce radiologic outliers. Although the clinical outcomes of robot-assisted UKA over a short-term follow-up period were not significantly different compared to those of conventional UKA, longer follow-up period is needed to determine whether the improved radiologic accuracy of the components in robotic-assisted UKA will lead to better clinical outcomes and improved long-term survival.

Klíčová slova:

Computed axial tomography – Knees – Medical implants – Orthopedic surgery – Osteoarthritis – Robotics – Surgical and invasive medical procedures


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2019 Číslo 12
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