Byung-Ho Yoon1, Michael A Mont2, Kyung-Hoi Koo3, Chung-Hwan Chen4, Edward Y Cheng5, Quanjun Cui6, Wolf Drescher7, Valerie Gangji8, Stuart B Goodman9, Yong-Chan Ha10, Philippe Hernigou11, Marc W Hungerford12, Richard Iorio13, Woo-Lam Jo14, Lynne C Jones15, Vikas Khanduja16, Harry K W Kim17, Shin-Yoon Kim18, Tae-Young Kim19, Hee Young Lee20, Mel S Lee21, Young-Kyun Lee3, Yun Jong Lee22, Junichi Nakamura23, Javad Parvizi24, Takashi Sakai25, Nobuhiko Sugano26, Masaki Takao25, Takuaki Yamamoto27, De-Wei Zhao28. 1. Department of Orthopaedic Surgery, Inje University College of Medicine, Seoul Paik Hospital, Seoul, South Korea. 2. Department of Orthopaedic Surgery, Lenox Hill Hospital, Northwell Health, New York, NY. 3. Department of Orthopaedic Surgery, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea. 4. Department of Orthopaedic Surgery, Kaoshiung Medical University Hospital, Kaohsiung, Taiwan. 5. Department of Orthopaedic Surgery, University of Minnesota Medical School, Minneapolis, MN. 6. Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA. 7. Department of Orthopedic and Trauma Surgery, RWTH Aachen University, Aachen, Germany. 8. Department of Rheumatology and Physical Medicine, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium. 9. Department of Orthopaedic Surgery, Stanford University School of Medicine, Redwood City, CA. 10. Department of Orthopaedic Surgery, Chung-Ang University College of Medicine, Seoul, South Korea. 11. Hôpital Henri Mondor, Creteil, France. 12. Department of Orthopedic Surgery, Mercy Medical Center, Baltimore, MD. 13. Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA. 14. Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea. 15. Department of Orthopaedic Surgery, Center for Metabolism and Obesity Research, Johns Hopkins, University School of Medicine, Baltimore, MD. 16. Department of Trauma & Orthopaedics, Addenbrooke's, Cambridge University Hospitals, Cambridge, UK. 17. Center for Excellence in Hip Disorders, Scottish Rite Hospital for Children, UT Southwestern Medical Center, Dallas, TX. 18. Department of Orthopedic Surgery, Graduate School of Medicine, Kyungpook National University, Daegu, Republic of Korea. 19. Department of Orthopedic Surgery, KonKuk University Medical Center, Seoul, South Korea. 20. Center for Preventive Medicine and Public Health, Seoul National University Bundang Hospital, Seongnam, South Korea. 21. Department of Orthopaedic Surgery, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan. 22. Department of Internal Medicine, Seoul National University Bundang Hospital and Medical College of Seoul National University, Seongnam, South Korea. 23. Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba City, Chiba, Japan. 24. Department of Orthopedic Surgery, Rothman Orthopaedic Institute, Philadelphia, PA. 25. Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Japan. 26. Department of Orthopaedic Medical Engineering, Osaka University Graduate School of Medicine, Suita, Osaka, Japan. 27. Department of Orthopaedic Surgery, Faculty of Medicine, Fukuoka University, Jonan-ku, Fukuoka, Japan. 28. Department of Orthopedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, China.
Abstract
BACKGROUND: The Association Research Circulation Osseous (ARCO) presents the 2019 revised staging system of osteonecrosis of the femoral head (ONFH) based on the 1994 ARCO classification. METHODS: In October 2018, ARCO established a task force to revise the staging system of ONFH. The task force involved 29 experts who used a web-based survey for international collaboration. Content validity ratios for each answer were calculated to identify the levels of agreement. For the rating queries, a consensus was defined when more than 70% of the panel members scored a 4 or 5 rating on a 5-point scale. RESULTS: Response rates were 93.1%-100%, and through the 4-round Delphi study, the 1994 ARCO classification for ONFH was successfully revised. The final consensus resulted in the following 4-staged system: stage I-X-ray is normal, but either magnetic resonance imaging or bone scan is positive; stage II-X-ray is abnormal (subtle signs of osteosclerosis, focal osteoporosis, or cystic change in the femoral head) but without any evidence of subchondral fracture, fracture in the necrotic portion, or flattening of the femoral head; stage III-fracture in the subchondral or necrotic zone as seen on X-ray or computed tomography scans. This stage is further divided into stage IIIA (early, femoral head depression ≤2 mm) and stage IIIB (late, femoral head depression >2 mm); and stage IV-X-ray evidence of osteoarthritis with accompanying joint space narrowing, acetabular changes, and/or joint destruction. This revised staging system does not incorporate the previous subclassification or quantitation parameters, but the panels agreed on the future development of a separate grading system for predicting disease progression. CONCLUSION: A staging system has been developed to revise the 1994 ARCO classification for ONFH by an expert panel-based Delphi survey. ARCO approved and recommends this revised system as a universal staging of ONFH.
BACKGROUND: The Association Research Circulation Osseous (ARCO) presents the 2019 revised staging system of osteonecrosis of the femoral head (ONFH) based on the 1994 ARCO classification. METHODS: In October 2018, ARCO established a task force to revise the staging system of ONFH. The task force involved 29 experts who used a web-based survey for international collaboration. Content validity ratios for each answer were calculated to identify the levels of agreement. For the rating queries, a consensus was defined when more than 70% of the panel members scored a 4 or 5 rating on a 5-point scale. RESULTS: Response rates were 93.1%-100%, and through the 4-round Delphi study, the 1994 ARCO classification for ONFH was successfully revised. The final consensus resulted in the following 4-staged system: stage I-X-ray is normal, but either magnetic resonance imaging or bone scan is positive; stage II-X-ray is abnormal (subtle signs of osteosclerosis, focal osteoporosis, or cystic change in the femoral head) but without any evidence of subchondral fracture, fracture in the necrotic portion, or flattening of the femoral head; stage III-fracture in the subchondral or necrotic zone as seen on X-ray or computed tomography scans. This stage is further divided into stage IIIA (early, femoral head depression ≤2 mm) and stage IIIB (late, femoral head depression >2 mm); and stage IV-X-ray evidence of osteoarthritis with accompanying joint space narrowing, acetabular changes, and/or joint destruction. This revised staging system does not incorporate the previous subclassification or quantitation parameters, but the panels agreed on the future development of a separate grading system for predicting disease progression. CONCLUSION: A staging system has been developed to revise the 1994 ARCO classification for ONFH by an expert panel-based Delphi survey. ARCO approved and recommends this revised system as a universal staging of ONFH.
Authors: Helder de Souza Miyahara; Lucas Verissimo Ranzoni; Leandro Ejnisman; José Ricardo Negreiros Vicente; Alberto Tesconi Croci; Henrique Melo de Campos Gurgel Journal: Rev Bras Ortop (Sao Paulo) Date: 2022-06-30
Authors: Jeremy T Hines; Woo Lam Jo; Quanjun Cui; Michael A Mont; Kyung Hoi Koo; Edward Y Cheng; Stuart B Goodman; Yong Chan Ha; Phillippe Hernigou; Lynne C Jones; Shin Yoon Kim; Takashi Sakai; Nobuhiko Sugano; Takuaki Yamamoto; Mel S Lee; Dewei Zhao; Wolf Drescher; Tae Young Kim; Young Kyun Lee; Byung Ho Yoon; Seung Hoon Baek; Wataru Ando; Hong Seok Kim; Jung Wee Park Journal: J Korean Med Sci Date: 2021-06-21 Impact factor: 2.153