3.0 T conventional hip MR and hip MR arthrography for the acetabular labral tears confirmed by arthroscopy

Objective

To evaluate the value of hip MR for diagnosing acetabular labrum tears, and to further compare the diagnostic performances of conventional MR with MR arthrography in acetabular labrum tears.

Methods

90 patients undergoing both hip MR examination and subsequent hip arthroscopy were retrospectively evaluated. Of these patients, 34 accepted both conventional MR and MR arthrography; while the other 56 only underwent conventional MR examination. All hip MR images were independently reviewed by two radiologists, and further compared with the results of hip arthroscopy.

Results

59 of 90 patients were confirmed with acetabular labral tears by hip arthroscopy and 31 without tears. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of conventional MR for evaluating the acetabular labral tears were 61.0%, 77.4%, 83.7% and 51.1% (radiologist A), and 66.1%, 74.2%, 82.9% and 53.4% (radiologist B), respectively, with good consistency between the two observers (K = 0.645). The sensitivity, specificity, PPV and NPV of MR arthrography for assessing the acetabular labral tears were 90.5%, 84.6%, 90.5% and 84.6% (radiologist A), and 95.2%, 84.6%, 90.9% and 91.7% (radiologist B), respectively, with excellent good consistency between the two observers (K = 0.810). The sensitivity and NPV of MR arthrography for diagnosing the acetabular labral tears were significantly higher than those of conventional MR (both P < 0.05).

Conclusion

Hip MR arthrography is a reliable evaluation modality for diagnosing the acetabular labral tears, and its diagnostic performance is superior to that of conventional MR at 3.0 T.     

3.0T常规MRI与MR髋关节造影诊断髋臼唇撕裂的对比研究

目的 在3.0 T场强中,比较常规髋关节MRI及MR髋关节造影对髋臼唇撕裂的诊断价值.方法 回顾分析44例髋关节病变患者的患侧髋关节常规MRI及MR髋关节造影资料,将每例患者的臼唇划分为前、上、后3处区域(共计132处),确定有无撕裂,并进行分型.其中5例患者经髋关节镜检查.对于常规MRI及MR髋关节造影获得的臼唇撕裂及分型数据差异比较采用Wilcoxon秩和检验,一致性比较采用Kappa检验.结果 常规MRI与MR髋关节造影诊断完全相同者计116处臼唇,只有16处存在诊断差异.其中,前者诊断无撕裂而后者诊断撕裂者9处,前者诊断撕裂但后者诊断无撕裂者6处,其余1处两者均诊断为撕裂但分型不同.常规MRI与MR髋关节造影的评价差异没有统计学意义(Z=0.347,P＞0.05),且具有极好的一致性(K=0.781,P＜0.01).在接受关节镜的5例患者中,常规MRI、MR髋关节造影及关节镜结果均完全吻合.结论 对髋臼唇撕裂,3.0 T常规髋关节MRI可获得与MR髋关节造影基本相同的诊断效果.     

Evaluation of radial-sequence imaging in detecting acetabular labral tears at hip MR arthrography

Objective In recent years, radial imaging has been advocated for improved visualization of the acetabular labrum in magnetic resonance arthrography of the hip. The purpose of this study was to investigate whether radial imaging demonstrates labral tears not visible on standard imaging planes. Methods Fifty-four consecutive magnetic resonance (MR) arthrograms of the hip that included radial imaging over 2 years were retrospectively analyzed by two radiologists. Standard imaging planes and radial imaging were reviewed for identification of labral tears in four specific areas of the labrum: anterosuperior, posterosuperior, anteroinferior, and posteroinferior. The standard imaging sequences include fat-saturated spin-echo T1-weighted images in the coronal and oblique axial planes, non-fat-saturated T1-weighted images in the coronal and sagittal planes, and T2-weighted sequence in the axial plane. Radial imaging was performed as previously described using fat-saturated T1-weighted sequences. Results Using standard imaging planes, 50 anterosuperior, 31 posterosuperior, 10 anteroinferior, and 9 posteroinferior labral tears were detected in 54 MR arthrograms of the hip. Using radial sequences alone, 44 anterosuperior, 25 posterosuperior, 9 anteroinferior, and 5 posteroinferior labral tears were detected. In all four areas of the labrum, the radial imaging did not show any labral tear not seen on standard imaging planes. Discussion In MR arthrography of the hip, radial imaging did not reveal any additional labral tears. Standard imaging planes sufficiently demonstrate all acetabular labral tears.     

Sensitivity of MR arthrography in the evaluation of acetabular labral tears

OBJECTIVE: MRI has historically provided suboptimal visualization of tears of the acetabular labrum. Degenerative fraying and underlying cartilage abnormalities can often mimic tears of the labrum on conventional MRI. Administration of intraarticular gadolinium enhances the MRI appearance of the labrum to improve detection of labral abnormalities. This study examined the improved diagnostic sensitivity of MR arthrography compared with conventional MRI and the importance of confining the study to a small field of view. MATERIALS AND METHODS: Fifty-one hips were imaged in 48 patients. Fourteen hips underwent conventional MRI with a large field of view (30-38 cm). Seven hips underwent conventional MRI with a small field of view (14-20 cm). Thirty hips underwent MR arthrography with a small field of view (14-20 cm). Labral tears were diagnosed when contrast material was identified within the labrum or between the labrum and the acetabulum, when a displaced fragment was noted, or when a paralabral cyst was identified. All study results were compared with findings at the time of hip arthroscopy. RESULTS: Conventional MRI with a large field of view was 8% sensitive in detecting labral tears compared with findings at the time of arthroscopy. Diagnostic sensitivity was improved to 25% with a small field of view. MR arthrography with a small field of view was 92% sensitive in detecting labral tears. CONCLUSION: A combination of MR arthrography and a small field of view is more sensitive in detecting labral abnormalities than is conventional MRI with either a large or a small field of view.     

Prognostic value of chondral defects on the outcome after arthroscopic treatment of acetabular labral tears

Pathology of the acetabular labrum plays an increasing role in the treatment of hip pain. Hip arthroscopy has proven its clinical value as a useful procedure for successful treatment of labral tears. Until today, only a few studies have investigated the influence of articular cartilage defects on the clinical outcome of partial arthroscopic labrum resection in a larger patient population. We prospectively evaluated patients with an intraoperatively proven labral lesion/tear without any radiological and arthroscopical sign of a concomitant bony femoroacetabular impingement or hip dysplasia for a minimum postoperative follow-up of 2 years. Cartilage defects were classified according to Outerbridge and divided into two subgroups: Outerbridge ≤ 1 and Outerbridge ≥ 2, respectively. To evaluate combined results, various established scoring systems (visual analogue scale, modified Harris Hip Score, Larson Hip Score) were used. Out of 54 originally enrolled patients, 50 individuals (29 female, 21 male) with a median age of 33 years (range 15–49) were available for follow-up after a mean of 34 (range 24–48) months. At follow-up, the total study population experienced significant improvement in pain and in the combined evaluation scales (Larson Hip Score/MHHS). When patients were categorized into two subgroups, either with intraoperatively present or absent articular cartilage defects, our data indicated that subjects with no degenerative changes of the articular cartilage surface significantly improved in the applied clinically scoring systems. In contrast, in patients with an articular cartilage lesion during hip arthroscopy score values had a tendency to be unimproved or even deteriorated at follow-up. Regression analysis revealed a significant negative correlation between postoperative outcome and the grading of the coexistent articular cartilage defect. On the basis of our investigation, we conclude that partial arthroscopic resection of a torn labrum without attending bone deformity (dysplasia or femoroacetabular impingement) can reveal good and satisfied results. Depending on the extent of a coexisting articular cartilage defect subjective clinical results are compromised.     

Evaluation of the acetabular labrum at 3.0-T MR imaging compared with 1.5-T MR arthrography: preliminary experience

Institutional review board approval and informed consent were obtained for this HIPAA-compliant study. The purpose of this study was to prospectively compare imaging of the acetabular labrum with 3.0-T magnetic resonance (MR) imaging and 1.5-T MR arthrography. Eight patients (four male, four female; mean age, 38 years) with hip pain suspicious for labral disease were examined at both MR arthrography and MR imaging. Presence of labral lesions, paralabral cysts, articular cartilage lesions, subchondral cysts, osteophytes, and synovial herniation pits was recorded. There was arthroscopic correlation of findings in five patients. MR imaging depicted four surgically confirmed labral tears that were identified at MR arthrography, as well as one that was not visualized at MR arthrography. MR imaging helped identify all other pathologic conditions that were diagnosed at MR arthrography and helped identify one additional surgically confirmed focal articular cartilage lesion. These results provide encouraging support for evaluation with 3.0-T MR imaging over 1.5-T MR arthrography.     

Sensitivity and specificity in detection of labral tears with 3.0-T MRI of the shoulder

OBJECTIVE: MRI of the shoulder has been found to be sensitive and specific for detection of labral tears at 1.5 T or lower field strength compared with arthroscopy, whereas 3.0-T MRI of the shoulder has not been specifically assessed. This study assesses the sensitivity and specificity of MRI at 3.0 T for labral tears compared with arthroscopy. CONCLUSION: MRI of the shoulder at 3.0 T is very sensitive and specific compared with arthroscopy in detection of superior, anterior, and posterior labral tears.     

Sublabral sulcus at the posteroinferior acetabulum: a potential pitfall in MR arthrography diagnosis of acetabular labral tears

OBJECTIVE: Our study correlated findings on hip MRI and MR arthrography with hip arthroscopy to assess the location, prevalence, and potential pitfall of a normal acetabular sublabral sulcus. MATERIALS AND METHODS: We retrospectively collected 58 hip MRI studies along with surgical reports in 58 patients who underwent hip arthroscopy over a 5-year period. Intraoperative photography (n = 23), radiography (n = 56), unenhanced MRI (n = 13), and MR arthrography (n = 54) studies were available for review. Two radiologists described hip anatomy on radiology studies with agreement by consensus. RESULTS: A normal posteroinferior sublabral groove was confirmed on available arthroscopy photographs in four (17.4%) of 23 hips. In each of these four patients, the anatomic sublabral groove correlated with apparent partial labral detachment on MR arthrography. On review of all studies, 13 hips (22.4%) without a posterior labral tear at surgery had imaging findings of a sublabral sulcus. The sulcus was not associated with acetabular dysplasia, which was radiographically noted in 12 cases (21.4%). Preoperatively, the sulcus was misdiagnosed as a tear in two cases. Labral tears were anterior or anterosuperior in 51 patients. CONCLUSION: A posteroinferior sublabral groove is a relatively common normal anatomic hip variation. If not recognized as normal, the sulcus may serve as a diagnostic pitfall on MR arthrography. Its location is distinct from most labral tears. We did not discover a sublabral sulcus at the anterior or anterosuperior acetabulum, the most common sites of labral injury.     

髋关节MR造影在髋臼唇撕裂诊断中的应用

目的 探讨髋关节MR造影在髋臼唇撕裂诊断中的应用价值.方法 临床高度怀疑髋臼唇撕裂的15例20个髋关节在透视下行髋关节穿刺造影,采用SE T1WI加脂肪抑制技术,进行髋关节冠状面、矢状面、斜轴面及放射状位扫描.其中12例行关节镜检查.结果 在行髋关节镜检查的12例14个髋关节中,11例13个髋关节MR造影诊断为髋臼唇撕裂,与关节镜诊断相符;1例MR造影示正常,关节镜检查亦未发现髋臼唇撕裂.13个髋臼唇撕裂中位于前上象限12个髋关节,后上象限1个髋关节.在关节镜诊断髋臼唇撕裂的13个髋关节中,MR造影冠状面诊断髋臼唇撕裂3个髋关节,矢状面诊断10个髋关节,斜轴面及放射状位诊断髋臼唇撕裂均为13个髋关节.15例20个髋关节中有5例6个髋关节在后下象限有髋臼唇下沟表现.结论 MR髋关节造影是诊断髋臼唇撕裂的可靠方法,扫描方法应选择T1WI加脂肪抑制的矢状面及斜轴面或矢状面加放射状位.后下象限撕裂的诊断中应注意正常变异的存在.

Abstract：

Objective To investigate the application value of MR rthrography (MRA) in the diagnosis of acetabular labral tears. Methods Fifteen patients with a high degree of suspected acetabular labral tears received fluoroscope-guided injection of the contrast media into the hip joint ( hip arthrography) and fat-saturated spin-echo T1-weighted images were obtained in the coronal, sagittal, oblique-axial and radial planes. Hip arthroscopy was performed on 12 of them. Results Labral tears which were diagnosed in 11 patients by hip MRA were confirmed at hip arthroscopy. One patient showed no MRA indication of labral tear, also showed normal on arthroscopy. Tear in the anterior-superior quadrant 10 cases of 12 joints ( 12/13), posterior-superior quadrant 1 case of a joint (1/13). In 11 patients who underwent arthroscopy, hip MRA diagnosed 3 (3/13) joints labral tears in coronal planes, 10 (10/13) joints in sagittal planes and 13 (13/13) labral tears in axial-oblique and radial planes. In 15 patients with 20 hip joints, 5 cases 6 joints (6/20) with normal acetabular sublabral sulcus were performed. Conclusions MR arthrography of hip is a reliable method in the diagnosis of acetabular labral tears. Scanning method should be included fat-saturated spin-echo T1-weighted images in sagittal and oblique-axial planes or sagittal plus radial planes. The diagnosis of tor posterior-inferior quadrant should pay attention to the existence of a normal variation.     

3．0T三维各向同性肩关节MR关节成像与二维MR关节成像在诊断关节唇病变方面的比较

目的 使用3．0T成像设备比较三维各向同性MR关节成像与二维MR关节成像对肩关节唇病变的诊断准确性。方法 机构审查委员会批准本回顾性研究，免除了知情同意书。2006年3月—2007年1月，100例病人经3．0T成像设备进行三维各向同性和二维肩关节成像，随后接受关节镜手术。     

MR arthrographic appearance of the postoperative acetabular labrum in patients with suspected recurrent labral tears

OBJECTIVE: The objective of our study was to evaluate the MR arthrographic appearance of the acetabular labrum in patients with a suspected recurrent acetabular labral tear after previous arthroscopic resection of a labral tear. CONCLUSION: The labrum after excision will appear shortened on MR arthrography. A recurrent labral tear can be diagnosed by the identification on MR arthrography of a new line to the labral surface, an enlarged and distorted labrum, or a new paralabral cyst.     

评价肩袖肌腱撕裂:多层螺旋CT关节成像与1.5TMR关节成像的比较

摘要目的比较多层螺旋CT关节成像与1.5T MR关节成像对于肩袖损伤的诊断价值。材料与方法本研究已获得伦理委员会批准,且所有受试者均签署知情同意书。对56例病人分别行CT及MR关节成像,并由2名放射科医师独立评估     

The diagnostic accuracy of acetabular labral tears using magnetic resonance imaging and magnetic resonance arthrography: a meta-analysis

Objectives  

Magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) have been advocated for the diagnosis of acetabular labral tears. The purpose of this study was to determine the sensitivity and specificity of MRI and MRA in diagnosing acetabular labral tears using meta-analysis.     

Meta分析MRI及MR关节成像诊断髋臼盂唇撕裂准确性的研究

目的 MRI及MR关节成像(MRA)被推荐用于诊断髋臼盂唇撕裂。本研究的目的是用Meta分析法确定MRI及MRA诊断髋臼盂唇撕裂的敏感性及特异性。材料与方法     

MR arthrography for evaluation of the acetabular labrum

MR arthrography of the hip has provided new insights into the lesions underlying mechanical hip pain. Until now evaluation of these structures, especially the acetabular labrum, has been limited. With the joint distention provided by MR arthrography, labral detachments and intrasubstance tears can be identified and differentiated from the many varied appearances of the asymptomatic labrum. This article reviews the normal anatomy of the hip, the clinical presentation of internal derangement and the technique for performing MR arthrography. The variations in morphology and signal of the asymptomatic labrum are reviewed as well as the appearance of the abnormal labrum. Received: 16 January 2001 Revision requested: 21 January 2001 Revision received: 19 April 2001 Accepted: 19 April 2001     

MR imaging and MR arthrography for diagnosis of recurrent tears in the postoperative meniscus

The accuracy, pitfalls, and limitations of magnetic resonance (MR) imaging for diagnosing a tear in the nonoperated knee are well known. However, the diagnosis of a recurrent tear can be more difficult in the postoperative meniscus. Resection or meniscal repair results in postoperative changes that can mimic a recurrent tear. To serve as a foundation, the techniques of treatment for meniscal tears are reviewed. This is followed by a detailed review of the literature on the accuracy of diagnosis of a recurrent meniscal tear using MR imaging and MR arthrography. Finally, recommendations are given as to the circumstances in which MR imaging or MR arthrography should be used for evaluation of the postoperative meniscus.