MRI诊断膝关节半月板桶柄状撕裂

目的:总结分析半月板桶柄状撕裂的MRI征象和诊断价值.方法:回顾性分析146个经关节镜证实的膝关节MR图像,其中28个膝关节存在半月板桶柄状撕裂,记录如下5种MRI征象:碎块内移征、外周残半月板征、双PCL征、空领结征及双前角征,并分别计算每种征象诊断半月板桶柄状撕裂的敏感度、特异度、准确度、阳性预测值和阴性预测值.结...     

外侧半月板桶柄状撕裂低场MRI特殊征象分析

目的分析膝关节外侧半月板桶柄状撕裂(bucket-handletears,BHT)的低场MRI特殊征象。资料与方法回顾性分析12例经关节镜证实为膝关节外侧半月板BHT患者的低场强MRI图像,总结MRI征象,除碎块内移征、外周残半月板征、半月板翻转征、空领结征外,着重分析双前交叉韧带征、厚饼征、三韧带征。结果 12例外侧半月板BHT中,碎块内移征10例、外周残半月板征9例、半月板翻转征6例、空领结征12例、双前交叉韧带征3例、厚饼征4例、三韧带征3例。结论碎块内移征、外周残半月板征、半月板翻转征、空领结征见于内侧半月板BHT,同样见于外侧半月板BHT,前交叉韧带征、厚饼征和三韧带征为外侧半月板BHT特殊征象。     

半月板残破征在桶柄样撕裂中的MRI表现及其诊断价值

<正> 膝关节桶柄样撕裂作为纵行撕裂的特殊形式临床上并不少见,它的治疗方案和一般的半月板损伤不同,需要切除移位的半月板碎块。有关桶柄样撕裂的MRI征象很多,在冠状位及状位均有显示,其诊断价值各不相同。笔者回顾性总结本院经手术或关节镜证实的半月板桶柄样撕裂56例的MRI表现,探讨在矢状位上半月板大小形态的异常改变及其临床意义。     

MRI检查膝关节半月板桶柄样撕裂的临床价值分析

目的探讨MRI在膝关节半月板桶柄样撕裂诊断中的临床应用价值。方法对我院经关节镜证实为膝关节半月板损伤患者62例进行MRI检查。结果双前角征、髁间碎片征、双后交叉韧带征、领结消失征等四个征象对内侧半月板桶柄样撕裂的诊断敏感性分别为61.54%、92.31%、38.46%、76.92%,特异性均为100.00%。双前角征、髁间碎片征、双后交叉韧带征、领结消失征等四个征象对外侧半月板桶柄样撕裂的诊断敏感性分别为23.53%、47.06%、0.00%、70.59%。在28例膝关节半月板桶柄样撕裂中,有22例在MRI上出现了两种以上的征象,总体诊断敏感性为78.57%。对比分析发现内侧半月板桶柄样撕裂在双前角征、髁间碎片征、双后交叉韧带征等征象下诊断敏感性明显高于外侧半月板,且差异具有统计学意义。髁间碎片征是诊断内侧半月板桶柄样撕裂敏感性最高的征象(92.31%),特异性达100.00%。结论 MRI是诊断膝关节半月板桶柄样撕裂的有效方法,其对内侧半月板桶柄样撕裂的敏感性及特异性较外侧高,髁间碎片征对诊断内侧半月板桶柄样撕裂的来说最具价值,而外侧半月板桶柄样撕裂则很难利用该征象进行确诊。双前角征在诊断外侧半月板桶柄样撕裂时敏感性低,特异性高,而领结消失征则是敏感性高,特异性低,仅能作为诊断参考。     

MRI对膝关节半月板桶柄样撕裂的诊断价值

目的　评价MRI诊断膝关节半月板桶柄样撕裂的应用价值。方法　经关节镜证实的 2 1例的桶柄样撕裂患者及 11例非桶柄样撕裂患者。采用百胜公司的关节专用磁共振成像系统进行扫描。观察以下 4种MRI征象 ,双前角征 ,双后交叉韧带征 ,髁间碎片征及领结消失征。结果　 3 2例患者中 ,出现双前角征的有 10例 ,双后交叉韧带征 5例 ,髁间碎片征 2 0例 ,领结消失征 2 5例。结论　MRI是诊断半月板桶柄样撕裂的有效手段 ,内侧半月板桶柄样撕裂的敏感性及特异性较外侧高 ,髁间碎片征是诊断内侧半月板桶柄样撕裂最有价值的征象     

膝关节半月板桶柄样撕裂的MRI表现

目的 探讨膝关节半月板桶柄样撕裂的MRI特征.方法 搜集经手术或关节镜证实的膝关节半月板桶柄样撕裂56例,回顾性分析其MRI表现,总结MRI特征.结果 56例半月板桶柄样撕裂中,内侧半月板34例,外侧半月板22例,半月板碎块移位征42例,阳性率75%(42/56);双前(后)交叉韧带征36例,阳性率64.3%(36/56);半月板翻转征30例,阳性率53.6%(30/56);半月板双前角征24例,阳性率42.9%(24/56);领结缺如征39例,阳性率69.6%(39/56);外周残半月板征41例,阳性率73.2%(41/56).结论 膝关节半月板桶柄样撕裂具有典型的MRI特征,MRI对其诊断具有重要价值.     

MRI检查对半月板桶柄状撕裂的诊断价值研究

目的:探讨MR影像在膝关节半月板桶柄状撕裂(Bucket Handle Tear,BHT)中的诊断价值及MRI诊断BHT的观察方法。方法:采用敏感度、特异度等指标,盲法回顾分析130例同时行MRI及关节镜(Arthroscope,AS)检查治疗的膝关节损伤患者诊断结果,其中以经关节镜诊断BHT76例作为金标准,评价项目包括:①原始报告诊断;②中央移位的半月板碎片;③双后交叉韧带征;④蝶结消失征。结果:原始报告诊断BHT敏感度为43%,特异度为87%。中央移位的半月板碎片敏感度为72%,特异度为87%。双后交叉韧带征敏感度为31%,特异度为97%。蝶结消失征敏感度为71%,特异度为69%。结论:采用MRI诊断BHT时,中央移位的半月板碎片的特异度和敏感度均较高,而蝶结消失征的敏感度高,特异度低,双后交叉韧带征的特异度最高,敏感度最低。     

MR与关节镜诊断半月板损伤的临床价值研究

目的探讨MR与关节镜诊断半月板损伤的临床价值。方法本组72例患者检查86个膝关节,共172例半月板,入院后进行MRI检查评价半月板损伤情况,2周内进行膝关节镜检查,MRI检查结果按Fischer分级标准分I级信号、II级信号、III级信号,关节镜检查结果分正常、退变、撕裂。结果 MRI与关节镜检查诊断半月板损伤结果比较,X~2=1.432,P=0.698,κ=0.694;MRI与关节镜检查诊断半月板撕裂结果比较,X~2=0.529,P=0.629,κ=0.767,MRI诊断半月板撕裂的敏感度86.27%、特异度91.73%、阳性预测值81.48%、阴性预测值94.07%、阳性似然比10.43、阴性似然比0.15、准确度90.12%、假阳性率8.27%、假阴性率13.73%。结论 MRI能够较好的诊断半月板损伤的程度,特别是对半月板撕裂的诊断,MRI的Ⅲ级信号可作为临床选择关节镜检查和手术治疗的一个重要指征。     

膝关节半月板放射状撕裂的MRI表现

目的 探讨MRI对膝关节半月板放射状撕裂的检出能力.方法 回顾性分析1085例经关节镜证实的膝关节半月板损伤中的半月板放射状撕裂107例(9.9%)患者的MRI资料,同时按住院号顺序采用等足巨抽样方法 ,抽取100例经关节镜证实的非放射状撕裂的半月板损伤患者作为对照组.所有患者均经MR检查,观察裂隙征及裂隙行走征、半月板分离征、半月板消失征及小半月板征4种征象,与关节镜结果 比较.结果 (1)107例半月板放射状撕裂患者中,最常见的发生部位是外侧半月板体部(71例,66.4%)和前体交界部(25例,23.4%).(2)107例半月板放射状撕裂中,MRI诊断放射状撕裂102例.100例半月板非放射状撕裂的半月板损伤中,MRI诊断11例为放射状撕裂,MRI诊断半月板放射状撕裂的敏感度、特异度、阳性预测值、阴性预测值分别为95.3%(102/107)、89.0%(89/100)、90.3%(102/113)、94.7%(89/94).(3)裂隙征和半月板分离征出现频率最高,102例中分别出现59例(57.8%)和43例(42.2%),是诊断放射状撕裂最重要的MRI征象.结论 MRI诊断半月板放射状撕裂的准确率较高,是目前术前无创诊断的最佳方法 .     

膝关节半月板桶柄样撕裂的MR诊断

目的　研究膝关节半月板桶柄样撕裂的MR表现。方法　分析 38例经关节镜证实为半月板桶柄样撕裂的患者术前MR的特征性表现。结果　38例中 30例可见典型的撕裂半月板髁间窝内移位,半月板缺失或部分缺失征象; 5例仅显示半月板撕裂Ⅲ级信号; 3例无异常发现。结论　膝关节半月板桶柄样撕裂典型的MRI表现为撕裂半月板的游离缘关节内移位征象,但是当撕裂的游离缘未发生移位时,仅表现半月板撕裂的 3级信号,且与半月板的上下关节面均相通。     

Pitfalls and limitations of Magnetic Resonance Imaging in bucket-handle tears of knee menisci

PURPOSE: The aim of the present study was to assess the accuracy of magnetic resonance imaging (MRI) in the diagnosis of bucket-handle tears of the knee menisci, determining the sensitivity and specificity of the imaging for each of the signs typical of these tears. MATERIALS AND METHODS: MR examinations of 495 patients suffering from knee traumas were assessed retrospectively. Forty-eight patients had arthroscopically-proven bucket-handle tears of the meniscus. MR examinations were performed using a 0.5-T superconducting magnet, with T1-weighted spin-echo (SE) and gradient-echo (GE) T2*-weighted sequences. Imaging findings used for the diagnosis were: a) double posterior cruciate ligament sign; b) flipped meniscus sign; c) presence of a displaced fragment of the meniscus in the intercondylar notch, visible in coronal and axial images; d) truncated triangular shape of the peripheral non-displaced portion of the meniscus, visible in coronal images. RESULTS: A total of 43 out of 48 bucket-handle tears of the meniscus were correctly diagnosed at MR, thus overall MR accuracy was 98%. In 12 (28%) cases three signs were present simultaneously the double posterior cruciate ligament (sensitivity 28%, specificity 99%, accuracy 93%) + the displaced fragment in the intercondylar notch (sensitivity 69.8%, specificity 98.7%, accuracy 96.2%) + the truncated triangular shape of the peripheral portion of the meniscus (sensitivity 74.4%, specificity 98%, accuracy 96%). In 18 (42%) cases two signs were present together the displaced fragment of the meniscus + the truncated triangular shape of the peripheral portion of the meniscus. In 13 (30%) cases only one sign was presenting two cases the truncated triangular shape of the peripheral portion of the meniscus and in 11 cases the flipped meniscus sign (sensitivity 25.6%, specificity 93.4%, accuracy 87.5%). No statistically significant differences were found comparing the results for tears of the medial meniscus with those for the lateral meniscus. CONCLUSIONS: MR imaging is highly accurate in diagnosing bucket-handle tears of the menisci due to its ability to identify a displaced fragment of the meniscus in the intercondylar notch or flipped over the anterior horn of the meniscus of origin. We speculate that bucket-handle tears not found by MR imaging are cases where the meniscus was displaced after MR examination.     

Meniscal tears with fragments displaced in notch and recesses of knee: MR imaging with arthroscopic comparison

PURPOSE: To retrospectively evaluate magnetic resonance (MR) imaging for the depiction of meniscal tears with partially detached meniscal fragments displaced in the intercondylar notch or in the meniscal recesses of the knee. MATERIALS AND METHODS: The institutional review board required neither its approval nor informed patient consent for the retrospective review of patient data; however, informed patient consent had been obtained before the MR imaging examinations were performed. The presence of meniscal tears with notch and recess fragments was determined at MR imaging and at subsequent arthroscopy in 101 consecutive knees to determine the value of MR imaging for the depiction of these lesions. Initial reports were reviewed to evaluate results of initial interpretations. MR images were retrospectively analyzed to determine the value of several MR image signs for the detection of displaced tears with notch or recess fragments. RESULTS: At arthroscopy, 37 (41%) of 91 torn menisci had partially detached fragments. Twenty-six torn menisci had notch fragments, and 14 had recess fragments; three torn menisci had one notch and one recess fragment each. At initial MR image analysis, 38 (36%) of 105 torn menisci had partially detached fragments. Twenty-eight torn menisci had notch fragments, and 13 had recess fragments; one torn meniscus had two recess fragments, and three torn menisci had one notch and one recess fragment each. At initial analysis, sensitivities and specificities were, respectively, 69% and 94% for detection of tears with notch fragments and 71% and 98% for detection of tears with recess fragments. At retrospective analysis of sagittal MR images, the presence of at least one sign indicative of meniscal tear with a notch fragment had sensitivities and specificities, respectively, of 65% and 78% for observer 1 and 77% and 73% for observer 2. The presence of at least one sign indicative of a meniscal tear with a recess fragment had sensitivities and specificities, respectively, of 64% and 77% for observer 1 and 64% and 76% for observer 2. CONCLUSION: Meniscal tears with notch and recess fragments are frequently seen at arthroscopy and can be depicted at knee MR imaging with moderate sensitivity and high specificity.     

MR imaging of meniscal bucket-handle tears: a review of signs and their relation to arthroscopic classification

Our objective was to review the MR imaging signs of meniscal bucket-handle tears and assess the relevance of these signs to the arthroscopic classification of displaced meniscal tears. Forty-five menisci in 42 patients who had a diagnosis of bucket-handle tear either on MR imaging or on subsequent arthroscopy (in which Dandy's classification of meniscal tears was used) were retrospectively analyzed for MR imaging findings of double posterior cruciate ligament (PCL), fragment within the intercondylar notch, absent bow tie, flipped meniscus, double-anterior horn, and disproportional posterior horn signs. Arthroscopy, which was considered as the gold standard, revealed 41 bucket-handle tears (either diagnosed or not diagnosed by MR imaging) in 38 patients (33 males, 5 females). There was a stastistically significant male preponderance for the occurrence of meniscal bucket-handle tears. Overall, sensitivity and positive predictive value of MR imaging for the detection of meniscal bucket-handle tears were calculated as 90%. Common MR imaging signs of meniscal bucket-handle tears in arthroscopically proven cases of such tears were the fragment in the notch and absent bow tie signs (98% frequency for each). Double-PCL, flipped meniscus, double-anterior horn, and disproportional posterior horn signs, however, were less common (32, 29, 29, and 27%, respectively). An arthroscopically proven bucket-handle tear was found in all patients who displayed at least three of the six MR imaging signs of meniscal bucket-handle tears. The presence of three or more MR imaging signs of meniscal bucket-handle tears is highly suggestive of this condition. Electronic Publication     

半月板桶柄样撕裂的MRI表现

目的 探讨半月板桶柄样撕裂的MRI征象. 资料与方法 对经关节镜证实的半月板桶柄样撕裂56例(58侧)患者的MRI表现进行研究. 结果 领结残破征21膝,空领结征28膝,双前交叉韧带征6膝,双后交叉韧带征19膝,双半月板前角征11膝,前角异常肥大征5膝,双半月板后角征16膝,后角异常肥大7膝,后角残破征19膝,厚饼征6膝,半月板分离移位征53膝.合并膝关节囊积液58膝、股骨(或胫骨)挫伤36膝、内侧副韧带损伤6膝、前交叉韧带损伤5膝、后交叉韧带损伤9膝、关节软骨损伤13膝、骨梗死2膝. 结论 空(残)领结征、后角残破征、双后交叉韧带征及半月板分离移位征提示半月板桶柄样撕裂.     

Meniscal bucket handle tears: a retrospective study of arthroscopy and the relation to MRI

In this study, we aim to evaluate the arthroscopic findings of meniscal bucket handle tears and to correlate them with the proposed MR imaging signs of meniscal bucket handle tears suggested in the literature. Thirty-six patients who had a diagnosis of bucket handle tear in arthroscopy, in either medial or lateral meniscus, were included in our study (32 males and 4 females). Meniscal tears were evaluated in arthroscopy according to Dandys classification. The MRIs were retrospectively analyzed regarding the following findings: absence of bow tie sign, presence of double posterior cruciate ligament (PCL) sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign, and fragment within the intercondylar region. Locked types I and II fragment of medial meniscus and half-length, whole-width and whole length–half-width fragment of lateral meniscus in arthroscopy were basically correlated with fragment within the intercondylar notch and absent bow tie signs in MRI. We did not find the double PCL sign in any of the patients with a lateral meniscal bucket handle tear. The most common signs in MR images of meniscal bucket handle tears were the fragment in the notch sign and the absent bow tie sign. They were observed with equal frequency of 88.8%. The presence of double PCL sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign were less common (41.66, 33, 25, and 27.7%, respectively). We conclude that the presence of at least two of the six MRI signs should be regarded as highly suggestive for bucket handle tears of menisci.     

Bucket-handle meniscal tears of the knee: sensitivity and specificity of MRI signs

OBJECTIVE: To determine the sensitivity and specificity of reported MRI signs in the evaluation of bucket-handle tears of the knee. DESIGN AND PATIENTS: A retrospective analysis of 71 knee MR examinations that were read as displaying evidence of a bucket-handle or "bucket-handle type" tear was performed. We evaluated for the presence or absence of the absent bow tie sign, the coronal truncation sign, the double posterior cruciate ligament (PCL) sign, the anterior flipped fragment sign, and a fragment displaced into the intercondylar notch. Sensitivity and specificity were calculated relative to the gold standard of arthroscopy. RESULTS: Forty-three of 71 cases were surgically proven as bucket-handle tears. The absent bow tie sign demonstrated a sensitivity of 88.4%. The presence of at least one of the displaced fragment signs had a sensitivity of 90.7%. A finding of both the absent bow tie sign and one of the displaced fragment signs demonstrated a specificity of 85.7%. The double PCL sign demonstrated a specificity of 100%. The anterior flipped meniscus sign had a specificity of 89.7%. CONCLUSIONS: Bucket-handle tears of the menisci, reported in about 10% of most large series, have been described by several signs with MRI. This report gives the sensitivity and specificity of MRI for bucket-handle tears using each of these signs independently and in combination. MRI is shown to be very accurate for diagnosing bucket-handle tears when two or more of these signs coexist.     

MR IMAGING OF DISPLACED MENISCAL TEARS OF THE KNEE: Importance of a "disproportional posterior horn sign"

Purpose: Meniscal tears associated with displaced fragments are clinically significant. We propose the "disproportional posterior horn sign" as a supportive criterion to identify a posterocentrally displaced meniscal fragment on MR imaging studies. If the meniscal posterior horn in the central portion appears larger than that in the peripheral section, it is considered positive for "disproportional posterior horn sign".Material and Methods: MR images obtained in 42 patients with 43 lesions, confirmed to have displaced meniscal tears, were included in this study. The MR images were retrospectively evaluated for the presence of the "disproportional posterior horn sign", as well as the other known signs.Results: The "disproportional posterior horn sign" was seen in 9 (20.9%) of 43 lesions, including 1 lateral discoid meniscal tear, 5 lateral meniscal tears and 3 medial meniscal tears. Five of them also had other signs of a displaced meniscal fragment. However, the remaining 4 cases only exhibited the "disproportional posterior horn sign". For the other MR signs, the "absent bow tie sign" was detected in 40 (93%) of 43 lesions, the "flipped meniscus sign" in 27 (62.8%) of 43 lesions, the "double posterior cruciate ligament sign" in 17 (39.5%) of 43 lesions and the "notch fragment sign" in 22 (51.2%) of 43 lesions.Conclusion: The "disproportional posterior horn sign" is helpful in demonstrating a posterocentrally displaced meniscal fragment, especially when other characteristic signs are unremarkable or absent.     

The value of the absent bow tie sign in MRI of bucket-handle tears

AIM: To assess the accuracy of the absent bow tie sign in diagnosing bucket handle meniscal tears (BHT) of the knee menisci. MATERIALS AND METHODS: During a 3-year period, we correlated the MRI and arthroscopic findings and the presence of the various signs. One hundred and seven knees were reviewed: 74 where either MRI or arthroscopy had identified a BHT and 33 which were either normal (31), or a simple tear was identified (2). All cases were reviewed by a single radiologist with a musculoskeletal interest blinded to the original results. Each was assessed for the presence of (1) a central meniscal fragment, (2) the double posterior cruciate ligament (PCL) sign, (3) the bow tie sign and (4) the contribution of a 3D-volume sequence. RESULTS: Optimal results were obtained using standard sequences and a 3D-volume sequence, giving a sensitivity of 74% and positive predictive value of 89%. The bow tie sign gave a sensitivity of 71% and positive predictive value of 76%, significantly less than previous reports. The 18 BHTs diagnosed by arthroscopy but missed by MRI showed other abnormal findings at MRI and were not reported as normal. CONCLUSION: We were not able to reproduce the previously reported high sensitivity and specificity of the absent bow tie sign. Despite optimization of all factors, the accurate diagnosis of a bucket handle tear remains difficult, and is most reliably made by identifying a central meniscal fragment, rather than relying on secondary signs such as the absent bow tie sign.     

Accuracy of MR imaging of the knee in adolescents

OBJECTIVE: A report in the orthopedics literature states that MR imaging for internal derangement of the knee has a lower accuracy in adolescents than in adults and may even provide spurious information that alters clinical management. This assertion has not been specifically addressed in the radiology literature. The purpose of our study was to determine the accuracy of MR imaging in adolescents with regard to injury of the cruciate ligaments and menisci. MATERIALS AND METHODS: A database search of our institution's records from January 1998 to July 2000 yielded 2140 MR examinations of the knee, all of which had been performed with a standard knee protocol on a 1.5-T magnet. Of these 2140 examinations, 156 included patients younger than 18 years. Fifty-nine of these patients underwent surgery, and the orthopedic surgeons' operative reports were used as the gold standard with which the MR imaging results were compared. Thirty-four boys and 25 girls who ranged in age from 11 to 17 years (mean age, 15 years) were examined. The clinical notes for the remaining 97 patients were evaluated for information about management and clinical improvement. RESULTS: The sensitivity and specificity values for MR imaging of the menisci and cruciate ligaments in adolescents were as follows: medial meniscus, 92% sensitivity and 87% specificity; lateral meniscus, 93% sensitivity and 95% specificity; anterior cruciate ligament, 100% sensitivity and 100% specificity; and posterior cruciate ligament, 0% sensitivity and 100% specificity. CONCLUSION: Our data suggest that MR imaging of the knee in adolescents is sensitive, specific, and accurate.