The Archives of Bone and Joint Surgery

The Archives of Bone and Joint Surgery

Collateral Ligament Tension Guided Medial Unicompartmental Knee Revision to a Kinematically Aligned Total Knee Arthroplasty

Document Type : TECHNICAL NOTE

Authors
Giorgio Cacciola 1
Daniele Vezza 2
Luigi Sabatini 2
1 University of Turin, Department of Orthopaedic and Traumatology, Turin, Italy
2 Humanitas “Gradenigo” Hospital, Department of robotic and mini invasive surgery, Turin, Italy
10.22038/abjs.2026.86819.3943
Abstract
Objectives: This study presents a novel approach to revising failed medial unicompartmental knee arthroplasty into kinematically aligned total knee arthroplasty using an augmented reality (AR) system (NextAR by Medacta International). Traditional methods involve mechanically aligned total knee arthroplasty (TKA), which can be complex and often requires additional components like stems and augments. The proposed technique builds on the caliper-based manual method by integrating AR-based navigation to enhance precision during surgery, particularly in maintaining the patient’s native joint line and soft tissue behavior. The procedure includes preoperative three-dimensional planning and intraoperative adjustments based on real-time data on collateral ligament elongation. This AR-assisted technique aims to reduce the technical challenges associated with unicompartmental knee arthroplasty (UKA) revisions, offering potential benefits for alignment accuracy and soft-tissue management.
        Level of evidence: V
Keywords
Augmented reality
Kinematic alignment
Medial UKA
NextAR
Revision
Subjects
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The Archives of Bone and Joint Surgery
Volume 14, Issue 7
July 2026
Pages 478-483

  • Receive Date 17 March 2025
  • Revise Date 25 June 2025
  • Accept Date 18 May 2026