Society for Arthroscopy and Joint Surgery (AGA) Research Committee (2026). A consensus-based classification of minor complications, major complications, and failure after anterior cruciate ligament reconstruction: A modified delphi study
Society for Arthroscopy and Joint Surgery (AGA) Research Committee
Faculty of Medicine Vienna
Link Campus University, University of Zurich, University Hospital Münster, Section of Sports Orthopaedics, Department of Trauma Surgery, Austrian Society for Regenerative Medicine (RegMed) and Austrian Research Group for Regenerative and Orthopedic Medicine (AURROM), Sigmund Freud Private University of Vienna, Medical University of Vienna, MedSciCare, Department of Clinical Research, Semmelweis University, Clinic for Trauma Surgery and Orthopaedics, Orthopaedicum Lich/Gießen, Gelenkpunkt, Technical University of Munich, Sporthopaedicum Regensburg, University Hospital Brandenburg an der Havel, OrthoZentrum Doebling, Lyon Ortho Clinic, Klinik Diakonissen Linz, St. Vinzenz Hospital, Schulthess Klinik – Schulthess Clinic, Albert-Ludwigs-University Freiburg, University of Pretoria, Past Chairman Department of Orthopaedic Sports MedicineTUMUniversity Hospital Rechts der Isar Ismaninger Street 22 Munich 81675, Center for Musculoskeletal Surgery, Gelenkzentrum Winterthur, Department of Trauma and Orthopaedic Surgery University Medical Center Hamburg – Eppendorf Hamburg Germany, Boston University School of Medicine and Harvard Medical School, Editor-in-chief, University of Basel, UPMC Freddie Fu Sports Medicine Center, University for Continuing Education Krems, HygCen Germany GmbH, University Hospital Essen, International Center for Orthopedics, Sportklinik, Fortius Clinic, Kazakh Medical University of Continuing Education
https://doi.org/10.1016/j.jisako.2026.101104
Abstract
INTRODUCTION: The aim of this study was to establish a consensus-based classification of postoperative events following anterior cruciate ligament reconstruction (ACLR), clearly distinguishing no complication/normal clinical course, minor complication, major complication, and failure, using a structured Delphi methodology among international experts in anterior cruciate ligament (ACL) surgery.
METHODS: A three-round modified Delphi process was conducted involving international high-volume ACL surgeons. An initial set of statements addressing potential postoperative events after ACLR was developed by a working group based on clinical expertise and contemporary literature. Panellists classified each statement as no complication/normal clinical course, minor complication, major complication, or failure. Consensus was predefined as ≥75% agreement within a single category. Statements reaching consensus were retained, whereas non-consensus statements were revised and re-evaluated in subsequent rounds.
RESULTS: Thirty-nine experts completed the first and second Delphi rounds, and 30 (76.9%) completed the third round. The initial 52 statements were expanded to 67 in round two and refined to 46 in round three. Consensus was achieved for 14 statements (26.9%) in round one, 21 statements (31.3%) in round two, and 20 statements (43.5%) in round three. Overall, consensus was reached for 55 statements, forming the final classification framework. The panel clearly distinguished graft failure-defined as graft insufficiency or symptomatic instability-from major complications requiring surgical intervention or associated with substantial morbidity, and from minor complications or expected postoperative findings. Notably, traumatic graft rupture following a clearly documented new injury was not considered a postoperative complication.
CONCLUSIONS: This international Delphi consensus establishes a standardised and clinically meaningful classification of postoperative events following ACLR. By clearly distinguishing no complication, minor complication, major complication, and failure, this framework provides a shared language that may improve consistency in outcome reporting, facilitate comparison across studies, and enhance the interpretability of clinical research and registry data.