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Meniscal extrusion

Last revised by Henry Knipe ◉ on 4 Jan 2022

Citation, DOI, disclosures and article data

Citation:

Weerakkody Y, Knipe H, Elfeky M, et al. Meniscal extrusion. Reference article, Radiopaedia.org (Accessed on 10 Mar 2025) https://doi.org/10.53347/rID-40591

DOI:

https://doi.org/10.53347/rID-40591

Permalink:

https://radiopaedia.org/articles/40591

rID:

40591

Article created:

27 Oct 2015, Yuranga Weerakkody ◉

Disclosures:

At the time the article was created Yuranga Weerakkody had no recorded disclosures.

View Yuranga Weerakkody's current disclosures

Last revised:

4 Jan 2022, Henry Knipe ◉

Disclosures:

At the time the article was last revised Henry Knipe had no recorded disclosures.

View Henry Knipe's current disclosures

Revisions:

10 times, by 8 contributors - see full revision history and disclosures

Systems:

Musculoskeletal

Tags:

knee

Synonyms:

Extrusion of meniscus
Extrusion of menisci
Meniscal subluxation

Meniscal extrusion or subluxation refers to the peripheral meniscal margin extending beyond the external aspect of the tibiofemoral compartment of the knee.

Pathology

This can result from disruption of collagen fibers within the meniscus that provide hoop strength ⁸.

Associations

medial meniscal extrusion is associated with osteoarthritis ^2,5
meniscal tears: can occur with many tears, but especially root tears ³
meniscal maceration ⁵
knee malalignment ⁵
high BMI (females) ⁹
female sex ¹⁰

Radiographic features

Meniscal extrusion can be assessed reliably on ultrasound and MRI ⁵ as well as on CT ⁷. Significant meniscal extrusion has been variably defined as ≥3 mm ¹ or ≥4 mm ⁶.

References

1. Costa C, Morrison W, Carrino J. Medial Meniscus Extrusion on Knee MRI: Is Extent Associated with Severity of Degeneration or Type of Tear? AJR Am J Roentgenol. 2004;183(1):17-23. doi:10.2214/ajr.183.1.1830017 - Pubmed
2. Wang Y, Wluka A, Pelletier J et al. Meniscal Extrusion Predicts Increases in Subchondral Bone Marrow Lesions and Bone Cysts and Expansion of Subchondral Bone in Osteoarthritic Knees. Rheumatology (Oxford). 2010;49(5):997-1004. doi:10.1093/rheumatology/keq034 - Pubmed
3. Crema M, Roemer F, Felson D et al. Factors Associated with Meniscal Extrusion in Knees with or at Risk for Osteoarthritis: The Multicenter Osteoarthritis Study. Radiology. 2012;264(2):494-503. doi:10.1148/radiol.12110986 - Pubmed
4. Rennie W & Finlay D. Meniscal Extrusion in Young Athletes: Associated Knee Joint Abnormalities. AJR Am J Roentgenol. 2006;186(3):791-4. doi:10.2214/AJR.04.1181 - Pubmed
5. Nogueira-Barbosa M, Gregio-Junior E, Lorenzato M et al. Ultrasound Assessment of Medial Meniscal Extrusion: A Validation Study Using MRI as Reference Standard. AJR Am J Roentgenol. 2015;204(3):584-8. doi:10.2214/AJR.14.12522 - Pubmed
6. Svensson F, Felson D, Turkiewicz A et al. Scrutinizing the Cut-Off for "Pathological" Meniscal Body Extrusion on Knee MRI. Eur Radiol. 2019;29(5):2616-23. doi:10.1007/s00330-018-5914-0 - Pubmed
7. Roemer F, Demehri S, Omoumi P et al. State of the Art: Imaging of Osteoarthritis-Revisited 2020. Radiology. 2020;296(1):5-21. doi:10.1148/radiol.2020192498 - Pubmed
8. Adams J, McAlindon T, Dimasi M, Carey J, Eustace S. Contribution of Meniscal Extrusion and Cartilage Loss to Joint Space Narrowing in Osteoarthritis. Clin Radiol. 1999;54(8):502-6. doi:10.1016/s0009-9260(99)90846-2 - Pubmed
9. Zhang F, Bierma-Zeinstra S, Oei E, Turkiewicz A, Englund M, Runhaar J. Factors Associated with Meniscal Body Extrusion on Knee MRI in Overweight and Obese Women. Osteoarthritis Cartilage. 2017;25(5):694-9. doi:10.1016/j.joca.2016.12.001 - Pubmed
10. Zhang F, Kumm J, Svensson F, Turkiewicz A, Frobell R, Englund M. Risk Factors for Meniscal Body Extrusion on MRI in Subjects Free of Radiographic Knee Osteoarthritis: Longitudinal Data from the Osteoarthritis Initiative. Osteoarthritis Cartilage. 2016;24(5):801-6. doi:10.1016/j.joca.2015.12.003 - Pubmed