Medıal Menıscus Extrusion on MRI: a Crıtıcal Indıcator for Hıgh-Rısk Tears and Assocıated Intra-Artıcular Pathologıes

LEMAN GÜNBEY KARABEKMEZ , ÜLKÜ KERİMOĞLU, MEMDUHA GUMUS, SEMA AKCAM, İBRAHİM TUNCAY

  • LEMAN GÜNBEY KARABEKMEZ: Ankara Yıldırım Beyazıt Üniversitesi Tıp Fakültesi
  • ÜLKÜ KERİMOĞLU: Konya Necmettin Erbakan Üniversitesi Tıp Fakültesi
  • MEMDUHA GUMUS: University of Pittsburgh Medical Center
  • SEMA AKCAM: KONYA NUMUNE HASTANESİ
  • İBRAHİM TUNCAY: SELÇUK ÜNİVERSİTESİ
  • Year : 2026
  • Vol : 42
  • Issue : 3
  •  Page : 224-233
Objective: To evaluate the relationship between medial meniscus (MM) tear morphology and meniscal extrusion, and to determine whether extrusion can be used as
an indicator for identifying high-risk tears based on knee MRI findings.
Materials and Methods: This retrospective study included 183 knee examinations from 160 patients. MM pathologies were classified as degeneration, horizontaloblique
tear, radial tear at the root region, and complex tear. Lateral meniscal pathologies, chondromalacia, joint effusion, and anterior cruciate ligament (ACL) status
were recorded. Meniscal extrusion was measured on coronal proton-density–weighted images. Intergroup differences were analyzed using the chi-square and Kruskal–
Wallis tests. Receiver operating characteristic (ROC) analysis was performed to predict high-risk tears. A multivariate logistic regression model was used to investigate
independent predictors of extrusion ≥3 mm.
Results: Radial root tears and complex tears demonstrated significantly greater extrusion compared with other pathologies. Chondromalacia and joint effusion were
significantly more frequent in knees with extrusion ≥3 mm. ACL rupture was associated with both increased extrusion and complex MM tears. ROC analysis identified
a threshold value of 3.27 mm (clinically approximated as 3 mm) for discriminating high-risk tears (sensitivity 84.4%, specificity 70.2%, AUC 0.82). In the regression
analysis, low-risk and high-risk tear groups as well as chondromalacia were identified as independent predictors of pathological extrusion.
Conclusion: MM extrusion, particularly values ≥3 mm, is a strong radiological indicator of radial root and complex tears and reflects accompanying degenerative
changes. Quantitative assessment of extrusion may contribute to the early diagnosis of surgically significant meniscal tears.
Cite this Article As : Gunbey Karabekmez L, Kerimoglu U, Gumus M, Akcam S, Tuncay I. Medial Meniscus Extrusion on MRI: A Critical Indicator for High-Risk Tears and Associated Intra-Articular Pathologies. Selcuk Med J 2026;42(3): 224-233

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Conflict of interest : The authors declare that they have no conflict of interest.
This article is published under the CC BY-NC 4.0 license.
Selcuk Medical Journal
2026, Vol. 42 (3)
ISSN: 1017-6616
E-ISSN: 2149-8059
Received : , Accepted : , Published Online :

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