J Knee Surg 2024; 37(01): 008-013
DOI: 10.1055/a-2179-8456
Special Focus Section

No Benefit of Robotic-Assisted over Computer-Assisted Surgery for Achieving Neutral Coronal Alignment in Total Knee Arthroplasty

1   AUVA UKH Steiermark, Graz, Austria
2   Johannes Kepler University, Linz, Austria
Victoria Anelli-Monti
1   AUVA UKH Steiermark, Graz, Austria
Stephanie Huber
3   Orthopedic Hospital Speising, Vienna, Austria
4   Michael Ogon Institute, Vienna, Austria
Maximillian Zacherl
1   AUVA UKH Steiermark, Graz, Austria
Jochen Hofstaetter
3   Orthopedic Hospital Speising, Vienna, Austria
4   Michael Ogon Institute, Vienna, Austria
Christian Kammerlander
1   AUVA UKH Steiermark, Graz, Austria
Patrick Sadoghi
5   Department for Orthopedics and Traumatology, Medical University of Graz, Graz, Austria
› Author Affiliations


The use of robotic-assisted surgery (RAS) in total knee arthroplasty (TKA) is becoming increasingly popular due to better precision, potentially superior outcomes and the ability to achieve alternative alignment strategies. The most commonly used alignment strategy with RAS is a modification of mechanical alignment (MA), labeled adjusted MA (aMA). This strategy allows slight joint line obliquity of the tibial component to achieve superior balancing. In the present study, we compared coronal alignment after TKA using RAS with aMA and computer-assisted surgery (CAS) with MA that has been the standard in the center for more than 10 years. We analyzed a prospectively collected database of patients undergoing TKA in a single center. Lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA) were compared for both techniques. In 140 patients, 68 CASs and 72 RASs, we observed no difference in postoperative measurements (median 90 degrees for all, LDFA p = 0.676, MPTA p = 0.947) and no difference in outliers <2 degrees (LDFA p = 0.540, MPTA p = 0.250). The present study demonstrates no benefit in eliminating outliers or achieving neutral alignment of both the femoral and the tibial components in robotic-assisted versus computer-assisted TKA if MA is the target. To utilize the precision of RAS, it is recommended to aim for more personalized alignment strategies. The level of evidence is level III retrospective study.

Publication History

Received: 13 July 2023

Accepted: 20 September 2023

Accepted Manuscript online:
21 September 2023

Article published online:
12 October 2023

© 2023. Thieme. All rights reserved.

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