膝關節內側半月板后根撕裂的MR影像征象

[摘要]目的 探討MR對膝關節內側半月板后根撕裂的影像診斷價值。 方法 回顧性分析40例經關節鏡確診膝關節內側半月板后根撕裂的MR影像學特征，并分析膝關節韌帶損傷及半月板脫位等伴隨征象。 結果 直接征象：40例患者中有36例MR上表現為內側半月板后根形態及信號的異常改變：軸位顯示內側半月板根部的放射狀撕裂，冠狀位顯示存在信號截斷，矢狀位表現為空半月板征。伴隨征象：半月板脫位：32/36例患者冠狀位表現為內側半月板脫位；關節韌帶損傷：14/36例患者矢狀位上可見前交叉韌帶形態改變及異常高信號；關節退變：34/36例患者關節軟骨內出現異常高信號影。 結論 MR是診斷內側半月板后根撕裂及其伴隨征象的有效檢查方法。

[關鍵詞]內側半月板；后根；撕裂

[中圖分類號] R687.3 [文獻標識碼] B [文章編號] 2095-0616（2012）22-100-03

MR imaging findings of posterior meniscal root tear of the medial meniscus

LIU Shan1 SUN He2

1.Department of Radiology，Shenyang the Forth Hospital of People，Shenyang 110031，China；2.Department of Radiology，the Fourth Affiliated Hospital of China Medical University，Shenyang 110032，China

[Abstract] Objective To explore diagnostic value of MR imaging on the medial meniscus root tear. Methods 40 patients confirmed by arthroscopy knee medial meniscus posterior root tear underwent MRI，and the imaging features and accompanied signs of ligaments injured and meniscus extrusion were reviewed retrospectively. Results Direct signs：Of the 40 patients，36 cases MR imaging appearanced abnormal of medial meniscus posterior root morphology and signal：the radial tear on the meniscal root of the medial meniscus in the axial plane，the presence of the truncation sign in the coronal plane and the ghost meniscus sign in the sagittal plane. Accompanied by signs：Meniscus extrusion：32 cases showed mendial meniscus extrusion in the coronal palne. Ligament injuried：the anterior ligaments morphological changes and abnormal high signal in 14 patients. Knee joint degeneration：articular cartilage of 34 cases with abnormally high signal intensity. Conclusion MR can effectively demonstrate imaging features of medial meniscal root tear and its accompanying signs.

[Key words] The medial meniscus；Posterior meniscal root；Tears

膝關節半月板根部附著于脛骨平臺中央，是保持周圍張力和防止半月板承受軸負荷移位的必要結構[1]。研究發現，在半月板后根撕裂的患者中，發生于內側半月板的病例要多于外側半月板。然而，內側半月板后根部很難在關節鏡下得到清晰的顯露，這就意味著術前對內側半月板后根撕裂的正確評價對于手術成功起到至關重要的作用[2]。隨著影像技術的的發展，MR已成為術前評估半月板后根撕裂的主要檢查手段。本研究回顧性分析經關節鏡證實的內側半月板后根撕裂的40例患者，探討其MR影像特征及伴隨的膝關節異常改變，為臨床治療提供可靠依據。……