Collins Mark S, Unruh Kenneth P, Bond Jeffrey R, Mandrekar Jayawant N
Department of Radiology, Mayo Clinic, Ch2-290, 200 First Street, SW, Rochester, MN 55905, USA.
Skeletal Radiol. 2008 Mar;37(3):233-43. doi: 10.1007/s00256-007-0423-2. Epub 2007 Dec 19.
To evaluate previously described primary and secondary MRI signs of disruption to anterior cruciate ligament (ACL) grafts in surgically proven cases.
We retrospectively analyzed MR images of 48 patients (mean age 29 years) with clinically suspected ACL graft disruption. All patients had surgical confirmation of the MRI findings. The reviewers analyzed the cases blinded to the surgical results and assessed each of the primary and secondary MRI signs of graft disruption individually. Subsequently, a final impression of the graft integrity based on a comprehensive assessment of all of the primary and secondary findings was made.
Utilizing a comprehensive assessment of previously described primary and secondary MR findings of ACL graft disruption, the blinded reviewers were able to identify correctly full-thickness graft tears with test accuracy of 85%, sensitivity of 72%, and specificity of 100%. Individual assessment of the primary finding of graft fiber discontinuity had sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 72%, 100%, 100%, 77% and 85%, respectively, for full-thickness tears. Other individual primary and secondary findings were less reliable; however, the primary findings of marked segmental thinning of the graft and markedly abnormal graft orientation, and the secondary findings of bone contusions in the lateral compartment and large joint effusion, had high specificity and positive predictive value. Of the four missed cases, two had associated arthrofibrosis.
The comprehensive assessment of previously described primary and secondary MRI findings of ACL graft disruption has high test specificity and moderately high test accuracy. The presence of graft fiber discontinuity is the most reliable primary or secondary finding when assessed individually. Marked segmental thinning of the graft and abnormal fiber orientation, and the presence of bone contusions in the lateral compartment and large joint effusion, are less reliable overall but are highly suggestive of full-thickness graft tear when present.
在经手术证实的病例中，评估先前描述的前交叉韧带（ACL）移植物断裂的主要和次要MRI征象。
我们回顾性分析了48例临床怀疑ACL移植物断裂患者（平均年龄29岁）的MR图像。所有患者均经手术证实MRI检查结果。阅片者在不知晓手术结果的情况下分析病例，并分别评估移植物断裂的主要和次要MRI征象。随后，基于对所有主要和次要发现的综合评估，对移植物完整性做出最终判断。
通过对先前描述的ACL移植物断裂的主要和次要MR表现进行综合评估，不知情的阅片者能够正确识别全层移植物撕裂，测试准确率为85%，敏感性为72%，特异性为100%。对于全层撕裂，移植物纤维连续性这一主要表现的个体评估的敏感性、特异性、阳性预测值、阴性预测值和准确率分别为72%、100%、100%、77%和85%。其他个体主要和次要表现的可靠性较低；然而，移植物明显节段性变薄和明显异常的移植物方向这两个主要表现，以及外侧间室骨挫伤和大量关节积液这两个次要表现，具有较高的特异性和阳性预测值。在4例漏诊病例中，2例伴有关节纤维性粘连。
对先前描述的ACL移植物断裂的主要和次要MRI表现进行综合评估具有较高的测试特异性和中等偏高的测试准确率。单独评估时，移植物纤维连续性的存在是最可靠的主要或次要表现。移植物明显节段性变薄和纤维方向异常，以及外侧间室骨挫伤和大量关节积液的存在，总体可靠性较低，但出现时高度提示全层移植物撕裂。
