Rotator cuff tears: assessment with MR arthrography in 275 patients with arthroscopic correlation

We assessed the diagnostic performance of magnetic resonance (MR) arthrography in the diagnosis of articular-sided partial-thickness and full-thickness rotator cuff tears in a large symptomatic population. MR arthrograms obtained in 275 patients including a study group of 139 patients with rotator cuff tears proved by arthroscopy and a control group of 136 patients with arthroscopically intact rotator cuff tendons were reviewed in random order. MR imaging was performed on a 1.0 T system (Magnetom Expert, Siemens). MR arthrograms were analyzed by two radiologists in consensus for articular-sided partial-thickness and full-thickness tears of the supraspinatus, infraspinatus, and subscapularis tendons. At arthroscopy, 197 rotator cuff tears were diagnosed, including 105 partial-thickness (93 supraspinatus, nine infraspinatus, three subscapularis) and 92 full-thickness (43 supraspinatus, 20 infraspinatus, 29 subscapularis) tendon tears. For full-thickness tears, sensitivity, specificity, and accuracy were 96%, 99%, and 98%, respectively, and for partial tears 80%, 97%, and 95%, respectively. False negative and positive assessments in the diagnosis of articular-sided partial-thickness tears were predominantly [78% (35/45)] observed with small articular-sided (Ellman grade1) tendon tears. MR arthrography is highly accurate in the diagnosis of full-thickness rotator cuff tears and is accurate in the diagnosis of articular-sided partial-thickness tears. Limitations in the diagnosis of partial-thickness tears are mainly restricted to small articular-sided tears (Ellman grade 1) due to difficulties in differentiation between fiber tearing, tendinitis, synovitic changes, and superficial fraying at tendon margins.     

Morton neuroma: effect of MR imaging findings on diagnostic thinking and therapeutic decisions.

PURPOSE: To determine the effect of magnetic resonance (MR) imaging results on diagnostic thinking and therapeutic decisions by orthopedic surgeons in cases of a possible Morton neuroma. MATERIAL AND METHODS: Orthopedic surgeons completed a questionnaire before and after MR imaging for 54 feet in 49 patients thought to have Morton neuroma. Clinical diagnosis (Morton neuroma, differential diagnosis), location, diagnostic confidence, and therapeutic decisions were noted before and after MR imaging. The influence of the size of the neuroma on therapeutic decisions was analyzed. MR imaging diagnoses were compared with surgical results for 23 revised intermetatarsal spaces. RESULTS: After MR imaging, the clinical diagnosis of Morton neuroma was withdrawn in 15 of 54 (28%) feet. In 14 of 39 maintained diagnoses, the location or number of neuromas was changed after MR imaging. Confidence levels for Morton neuroma increased substantially after MR imaging. In 31 (57%) feet, a change in treatment plan resulted after MR imaging. Diameters of neuromas on MR images were significantly larger (P = .003) in surgically treated feet than in conservatively treated feet. MR imaging diagnoses were correct in all 23 revised intermetatarsal spaces. CONCLUSION: MR imaging has a major effect on diagnostic thinking and therapeutic decisions by orthopedic surgeons when Morton neuroma is suspected, especially because MR imaging helps in localization and size assessment of Morton neuromas.     

Shoulder MR arthrography: which patient group benefits most?

OBJECTIVE: We sought to compare the diagnostic accuracy of conventional MRI versus MR arthrography of the shoulder in the assessment of high-performance athletes (professional baseball players) and to compare our findings in these patients with the conventional MRI and MR arthrographic findings in an age-matched control group of nonprofessional athletes. MATERIALS AND METHODS: Conventional MRI and MR arthrographic examinations of the shoulder in 20 consecutive professional baseball players with shoulder pain were reviewed retrospectively by two musculoskeletal radiologists in consensus. These interpretations were compared with retrospective consensus interpretations of conventional MRI and MR arthrographic examinations of the shoulder obtained in a control group of 50 consecutive nonprofessional athletes with shoulder pain. MR images were assessed for full- or partial-thickness supraspinatus tendon tears, superior labral anteroposterior (SLAP) tears, and anterior or posterior labral tears. RESULTS: In the 20 consecutive professional athlete patients, two full-thickness and six partial-thickness undersurface supraspinatus tendon tears were seen on MR arthrography but not seen on conventional MRI as well as six SLAP tears, two anterior labral tears, and one posterior labral tear. Three patients had both SLAP tears and full- or partial-thickness supraspinatus tendon tears. Of 14 patients with findings on MR arthrography that were not seen on MRI, 11 had arthroscopic correlation. In all 11, arthroscopic findings confirmed findings on MR arthrography. In the group of 50 nonprofessional athlete patients, five had additional findings on MR arthrography not seen on conventional MRI: two anterior labral tears, two partial-thickness supraspinatus tendon tears, and two SLAP tears. One patient had both a partial-thickness supraspinatus tendon tear and a SLAP tear seen on MR arthrography. The five patients with additional findings on MR arthrography had arthroscopy. In all five, arthroscopic findings confirmed the findings on MR arthrography. CONCLUSION: MR arthrography is considerably more sensitive for detection of partial-thickness supraspinatus tears and labral tears than conventional MRI. MR arthrography showed injuries in addition to those seen on conventional MRI in 14 of 20 patients in the high-performance athlete group. These results suggest high-performance athletes may be a subgroup of patients for whom MR arthrography yields considerably more diagnostic information than conventional MRI.     

Imaging findings in the dominant shoulder of throwing athletes: comparison of radiography, arthrography, CT arthrography, and MR arthrography with arthroscopic correlation

OBJECTIVE: Conventional radiography, arthrography, CT arthrography, and MR arthrography--including use of the abduction and external rotation position--were compared, with arthroscopic correlation, to determine the spectrum of abnormalities encountered and the relative benefits of each imaging method in the evaluation of shoulder lesions occurring in 17 throwing athletes. SUBJECTS AND METHODS: Each of 36 athletes with shoulder pain aggravated by abduction and external rotation was examined in a single visit during which conventional radiography, arthrography, CT arthrography, and MR arthrography were performed. In 17 of these athletes, imaging findings were compared with those at arthroscopy. All images were independently evaluated by two groups of musculoskeletal radiologists. RESULTS: Structures found to be affected were, in decreasing order of frequency, the following: the posterosuperior labrum, supraspinatus tendon, infraspinatus tendon, humeral head, glenoid cavity and rim, acromioclavicular joint, anteroinferior capsulolabral complex, biceps tendon, and subscapularis tendon. MR arthrography without and with abduction and external rotation yielded the highest sensitivity and specificity for all lesions with the exceptions of bone sclerosis and enthesophytes (which were best seen with CT arthrography). MR arthrography with abduction and external rotation was most accurate for diagnosis of rotator cuff and anteroinferior capsulolabral complex tears. CONCLUSION: On the basis of these preliminary results, we believe that MR arthrography with abduction and external rotation should be part of the imaging evaluation of shoulder pain in throwing athletes, owing to the high sensitivity of this imaging technique.     

Bizepsprobleme: Ultraschall, Magnetresonanztomographie und MR-Arthrographie

Ultrasound and MR imaging are competitive imaging modalities for the diagnosis of pathologic conditions of the biceps tendon. MR imaging has substantial advantages over ultrasound because biceps tendon lesions are most commonly located in the proximal part where lesions are hidden under the acromion for ultrasound assessment. The value of MR arthrography is substantiated by the capability to assess associated diagnoses which are otherwise difficult to assess. Associated diagnoses include full- and partial thickness tears of supraspinatus and subscapularis tendons, pulley lesions, and adhesive capsulitis (frozen shoulder). Moreover, MR arthrography is the method of choice for the assessment of superior labral anterior posterior (SLAP) lesions.     

Can isotropic fast gradient echo imaging be substituted for conventional T1 weighted sequences in shoulder MR arthrography at 3 Tesla?

PURPOSE: To assess the practical utility of isotropic shoulder imaging in patients undergoing MR arthrography. Isotropic shoulder imaging can be performed in less than three minutes with use of fast gradients. MATERIALS AND METHODS: Two experienced musculoskeletal radiologists retrospectively interpreted MR images of the shoulder in 100 consecutive patients undergoing MR arthrography of the shoulder. All patients underwent MRI of the shoulder in oblique coronal, oblique sagittal, and axial planes on a 3.0-Tesla MRI system. All patients had conventional fast spin-echo T1-weighted imaging. All patients also had thin section (0.4 mm) isotropic spoiled gradient echo images performed. A total of 67 of the 100 patients underwent subsequent arthroscopy and results were compared with MR interpretations. RESULTS: There were 41 full-thickness supraspinatus tendon tears, nine partial-thickness supraspinatus tendon tears (seven articular surface and two bursal surface), 21 superior labral, 18 anterior labral, and seven posterior labral tears demonstrated by consensus retrospective reading of the 100 shoulder MR exams. There was no difference in interpretation of the isotropic images as compared to the conventionally acquired images in the oblique coronal, oblique sagittal, and axial planes. Some patients had more than one finding on each exam. A total of 67 patients went on to arthroscopy. There were 41 full-thickness supraspinatus tendon tears, nine partial-thickness supraspinatus tendon tears, 21 superior labral, 18 anterior labral, and seven posterior labral tears demonstrated on arthroscopy. All full- and partial-thickness supraspinatus tendon tears seen at arthroscopy were seen on consensus MR reading. A total of 19 out of the 21 patients with superior labral anterior posterior (SLAP) tears at arthroscopy were seen on consensus MR reading. A total of 16 of the 18 anterior labral tears and six of the seven posterior labral tears seen at arthroscopy were seen on consensus MR reading. Some of the 67 patients had more than one finding on arthroscopy. CONCLUSION: Isotropic imaging of the shoulder is practical in clinical imaging when performed with use of fast gradients on a 3-Tesla system. Isotropic imaging provides the same clinical information as conventional imaging and can be acquired in less than three minutes.     

Evaluation of Rotator Cuff Tendon Tears: Comparison of Multidetector CT Arthrography and 1.5-T MR Arthrography

Purpose: To compare the diagnostic performance of multidetector computed tomographic (CT) arthrography and 1.5-T magnetic resonance (MR) arthrography in the evaluation of rotator cuff lesions, with arthroscopic correlation. Materials and Methods: This study was approved by the institutional ethical committee, and informed consent was obtained from all patients. CT and MR arthrographic images prospectively obtained in 56 consecutive patients, following the same arthrographic procedure, were independently evaluated by two radiologists. Arthroscopy, performed within 1 month of the imaging, was used as the reference standard. Sensitivity and specificity of CT and MR arthrography were compared by using the McNemar test. Interobserver and intertechnique agreement for detecting rotator cuff lesions were measured and compared with κ and Z statistics. The Bland-Altman method was used to determine interobserver and intertechnique agreement for measuring tendon tears. For grading fatty infiltration of rotator cuff muscles, κ and Z statistics were used. Results: There was no statistically significant difference in sensitivity and specificity between CT arthrography and MR arthrography in depiction of rotator cuff lesions. The respective sensitivity and specificity of CT arthrography were 92% and 93%-97% for the supraspinatus, 100% and 77%-79% for the infraspinatus, 75%-88% and 85%-90% for the subscapularis, and 55%-65% and 100% for the biceps tendon. The respective sensitivity and specificity of MR arthrography were 96% and 83%-93% for the supraspinatus, 88%-100% and 81%-83% for the infraspinatus, 75%-88% and 90%-100% for the subscapularis, and 65%-85% and 100% for the biceps tendon. Interobserver agreement was substantial to almost perfect (κ = 0.744-0.964 for CT arthrography; κ = 0.641-0.893 for MR arthrography), and intertechnique agreement was almost perfect (κ > 0.819). CT and MR arthrography both yielded moderate interobserver and intertechnique agreement for measuring rotator cuff tears and grading muscle fatty infiltration. Conclusion: Data suggest that CT and MR arthrography have similar diagnostic performance for the evaluation of rotator cuff tendon tears. ? RSNA, 2012.     

MR versus MR arthrography in detection of supraspinatus tendon tears in patients without previous shoulder surgery

Purpose

We report the prevalence of supraspinatus tendon tears seen on MR arthrography that are not seen on conventional MR exam in the same patient population.

Materials and methods

A total of 150 consecutive conventional shoulder MR and MR arthrography exams performed on the same patients who went on to arthroscopy were reviewed retrospectively by consensus reading of two musculoskeletal radiologists. Full-thickness supraspinatus tendon tears were assessed. None of the patients had previous shoulder surgery.

Results

There were 113 full-thickness supraspinatus tendon tears seen on conventional MR exam while there were 119 full-thickness supraspinatus tendon tears seen on MR arthrography. The six additional full-thickness supraspinatus tendon tears seen on MR arthrography but not seen on conventional MR exam were confirmed at arthroscopy.

Conclusions

Some full-thickness supraspinatus tendon tears are not seen on conventional MR exam but are seen on MR arthrography. This is most likely due to fibrosis at the supraspinatus tendon tear site simulating an intact tendon on conventional MR.     

Imaging of degenerative and posttraumatic disease in the shoulder joint with ultrasound

This article reviews the examination technique of shoulder ultrasound, normal and abnormal ultrasound findings in acute (posttraumatic) and chronic (degenerative) lesions. Moreover, it reviews the effectiveness of ultrasound in relation to magnetic resonance (MR) imaging. Most authors report that full-thickness tears of the supraspinatus can reliably be diagnosed by ultrasound. However, the simple diagnosis of a full-thickness rotator cuff tear is no longer sufficient for surgical management. The precise localization and size of rotator cuff tears as well as the extent of muscle degeneration is important for surgical planning. For this aspect and for partial-thickness tears of the supraspinatus, for subscapularis lesions as well as for lesions of the long biceps tendons there is no consensus regarding the diagnostic value of ultrasound. To the present, ultrasound (contrary to MR imaging) has failed to demonstrate that it consistently influences the clinician's degree of confidence in the clinical diagnosis or the treatment plan. Therefore, some orthopedic surgeons prefer MR imaging to ultrasound in the evaluation of rotator cuff tears and other abnormalities of the glenohumeral joint. Moreover, MR imaging, especially when combined with arthrography, represents a one-step investigation, which not only allows for assessment of rotator cuff lesion but also of lesions of the labrum (Bankart lesions, SLAP lesions), the joint capsule and the biceps tendon. It also demonstrates muscle atrophy, which represents an important predictor of surgical outcome in rotator cuff repair.     

Supraspinatus tendon tears: comparison of 3D US and MR arthrography with surgical correlation

Objective

The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard.

Materials and methods

In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small (<1 cm), medium (1-3 cm), and large (>3 cm).

Results

The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears.

Conclusion

Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears.     

Magnetic resonance visualization of surgical classification of rotator cuff tear: comparison with three-dimensional shoulder magnetic resonance arthrography at 3.0 T

The purpose was to evaluate the diagnostic feasibility of magnetic resonance arthrography (MRA) for surgical classification of rotator cuff tear (RCT). Two-dimensional (2D)/three-dimensional (3D) MRAs of 45 patients who underwent and subsequent arthroscopy were evaluated. Full-thickness tears of supraspinatus–infraspinatus tendon were classified based on surgical categories: crescentic, U-shaped, and L-shaped. Signal-to-noise ratios showed no significant difference (P> .05); however contrast-to-noise ratios were significantly higher on 2D MRA (P= .02). Diagnoses of RCTs using 3D MRA were similar to diagnoses using 2D MRA, but had a shorter imaging time. MR visualization for surgical classification was feasible. However, diagnosis of L-shaped tears was limited.     

Supraspinatus tendon tears: comparison of US and MR arthrography with surgical correlation

The aim of this study was to compare the diagnostic reliability of US with MR arthrography in diagnosing supraspinatus tendon tears. Surgical findings were used as the gold standard in detecting tears. A total of 44 patients were assessed with transverse and longitudinal US scans with respect to the long axis of the rotator cuff tendons and then examined with MR arthrography. This technique involved free-hand injection of contrast medium into the shoulder joint. At surgery 20 incomplete and 24 complete tears were observed. Ultrasound offered good results for the large tears, but its sensitivity decreased proportionally with the size of the tears. Magnetic resonance arthrography correctly diagnosed 43 tears, whereas only one false-negative diagnosis of tendinosis was made for a partial tear on the bursal side. Since it improves the diagnosis of small tears, MR arthrography must be performed on all patients for whom surgical repair is necessary in order to restore normal functions.     

Indirect MR arthrography of the shoulder: use of abduction and external rotation to detect full- and partial-thickness tears of the supraspinatus tendon

PURPOSE: To evaluate prospectively the accuracy of indirect magnetic resonance (MR) arthrography for supraspinatus tendon tears during neutral positioning or abduction and external rotation (ABER) and neutral positioning. MATERIALS AND METHODS: Informed consent was obtained in all patients, and the study was approved by the institutional review board. Indirect MR arthrography of the shoulder was performed in 51 symptomatic patients (14 female, 37 male; mean age, 47 years) in the neutral position (set 1) and in the neutral and ABER positions (set 2). Two readers independently interpreted both sets, and diagnoses were compared with arthroscopic findings. Diagnostic accuracy was calculated, and 95% confidence intervals were used to detect significant differences between sets. Diagnostic confidence was recorded by using a three-level confidence score. Differences between sets were evaluated by using the Wilcoxon signed rank test. Interobserver agreement was determined separately for each set and for all diagnoses, full-thickness tears, and partial-thickness tears. RESULTS: For full-thickness tears, there was no benefit to reading set 2. For reader 1, sensitivity and specificity were 95% and 100%, respectively, for set 1 and 100% and 100%, respectively, for set 2. For reader 2, sensitivity and specificity were 80% and 100%, respectively, for set 1 and 100% and 100%, respectively, for set 2. For partial-thickness tears, sensitivity was significantly higher after reading set 2. For reader 1, sensitivity and specificity were 71% and 88%, respectively, for set 1 and 93% and 100%, respectively, for set 2. For reader 2, sensitivity and specificity were 50% and 88%, respectively, for set 1 and 86% and 94%, respectively, for set 2. For both readers, diagnostic confidence for partial-thickness tears was significantly higher after reading set 2. After the interpretation of set 2, kappa values increased from 0.35 to 1.00 for full-thickness tears and from 0.12 to 0.63 for partial-thickness tears. CONCLUSION: Indirect MR arthrography with supplementary images obtained with patients in the ABER position significantly improved sensitivity and increased diagnostic confidence for partial-thickness tears of the supraspinatus tendon. Interobserver agreement was improved for both full- and partial-thickness tears.     

Shoulder after rotator cuff repair: MR imaging findings in asymptomatic individuals--initial experience

PURPOSE: To assess the magnetic resonance (MR) imaging appearance of the successfully repaired rotator cuff in an asymptomatic population. MATERIALS AND METHODS: Fifteen subjects who had undergone clinically successful rotator cuff repair were included in the study. All underwent functional testing of the affected shoulder and had good to excellent scores on the Constant scale. Standard MR imaging sequences were performed at 1.5 T, including oblique coronal fast spin-echo T2-weighted MR imaging with fat saturation. RESULTS: Three (10%) of 30 supraspinatus and infraspinatus tendons had normal signal intensity, and 16 (53%) had mildly increased signal intensity on fast spin-echo T2-weighted fat-saturated images, compatible with tendonitis or tendinosis. Three partial and four complete tears of the supraspinatus tendon and two partial and two complete tears of the infraspinatus tendon were seen. Other findings included subacromial-subdeltoid effusion (10 subjects), joint effusions (five subjects), and bone marrow edema (six subjects). CONCLUSION: Postoperative signal intensity changes consistent with tendonitis or tendinosis were common, and clinically "silent" partial and complete rotator cuff tears were seen. Such postoperative MR imaging findings should be interpreted with caution, and meticulous correlation with symptoms and clinical results is recommended.     

Indirect MR arthrography of the unexercised glenohumeral joint in patients with rotator cuff tears.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic utility of indirect MR arthrography of the unexercised glenohumeral joint in patients with rotator cuff tears confirmed by arthroscopy or arthrotomy as the gold standard. METHODS: Twenty-six patients underwent conventional MR imaging and indirect MR arthrography of the stationary glenohumeral joint using a wrap-around surface coil. Unenhanced T1-weighted spin echo/T2-weighted fast spin echo sequences and T1-weighted gradient echo sequences, adding spectral fat suppression after intravenous administration of contrast medium, were performed in the oblique coronal and oblique sagittal planes. Images were analyzed by three experienced radiologists in consensus. Levels of diagnostic confidence were evaluated using a four-point scale of diagnostic certainty. RESULTS: Performing indirect MR arthrography of the unexercised shoulder leads to a diagnostically efficient enhancement of joint fluid (120% at 4 minutes and 145% at 8 minutes after intravenous injection of gadodiamide). In terms of soft tissue delineation, characterization of rotator cuff tears was significantly improved by using enhanced fat-suppressed T1-weighted gradient echo sequences compared with conventional MR imaging. CONCLUSIONS: Indirect MR arthrography without glenohumeral joint exercise in the diagnosis of rotator cuff tears is feasible and represents a more convenient and less time-consuming alternative to indirect MR arthrography after joint exercise.     

Infraspinatus muscle atrophy: implications?

PURPOSE: To evaluate associated findings in patients who exhibited atrophy of infraspinatus muscle at magnetic resonance (MR) examination of their shoulders to clarify implications of this abnormality. MATERIALS AND METHODS: With an electronic database search, cases of advanced infraspinatus muscle atrophy in patients who underwent MR imaging during a 1-year period for evaluation of shoulder pain or dysfunction were identified. The analysis was restricted to cases interpreted by one reader who applied a standardized method of reporting. Associated MR imaging findings in these cases were tabulated. RESULTS: Advanced infraspinatus muscle atrophy was encountered in 51 (4.3%) of 1,191 MR examinations of the shoulder. Tears of the infraspinatus tendon were present in only 27 (53%) of 51 cases. In 46 (90%) of 51 cases, a full-thickness tear was present in the anterior portion of the rotator cuff. In 10 (20%) of 51 cases with infraspinatus muscle atrophy, cuff muscle atrophy was confined to the infraspinatus muscle. Cuff muscle atrophy was isolated to the infraspinatus muscle in four (17%) of 24 cases in which atrophy of the infraspinatus muscle was present despite an intact tendon. In none of the 51 cases was there a mass in the suprascapular or sphenoglenoid notch. CONCLUSION: Infraspinatus muscle atrophy typically occurs with tendon tears in the anterior aspect of the rotator cuff. Concomitant atrophy in the supraspinatus muscle often is present, but infraspinatus muscle atrophy can occur in isolation, and this finding does not imply that the infraspinatus tendon is ruptured.     

MR arthrography of the shoulder: comparison with conventional MR imaging

Twenty-three patients underwent both conventional MR imaging of the shoulder and MR shoulder arthrography for clinically suspected labral or rotator cuff abnormalities. Images obtained before and after contrast administration were studied independently, and without knowledge of clinical findings, by two radiologists for the presence of abnormalities of the glenoid labrum or rotator cuff. Results were correlated with surgical findings in all patients. Nine patients had surgically proved labral tears. MR arthrography detected all nine labral abnormalities, while six of the nine were missed on conventional MR imaging. Fourteen patients had surgically proved rotator cuff tears. MR arthrography detected 11 of the 14 tears and missed three partial tears on the bursal surface. Conventional MR imaging detected nine cuff tears and missed five tears; two of these were complete rotator cuff tears and three were partial tears of the undersurface of the rotator cuff. Our results suggest that MR arthrography enhances the accuracy of MR in the evaluation of the glenoid labrum and rotator cuff tendon.     

Supraspinatus tendon tears at 3.0?T shoulder MR arthrography: diagnosis with 3D isotropic turbo spin-echo SPACE sequence versus 2D conventional sequences

Objective

To assess the diagnostic performance of shoulder MR arthrography with 3D isotropic fat-suppressed (FS) turbo spin-echo sequence (TSE-SPACE) for supraspinatus tendon tears in comparison with 2D conventional sequences at 3.0?T.

Materials and methods

The study was HIPAA-compliant and approved by the institutional review board with a waiver of informed consent. Eighty-seven arthroscopically confirmed patients who underwent 3.0?T shoulder MR arthrography with 2D sequences and 3D TSE-SPACE were included in a consecutive fashion from March 2009 to February 2010. Two reviewers independently analyzed 2D sequences and 3D TSE-SPACE. Sensitivity, specificity, accuracy, and interobserver agreement (κ) were compared between 2D sequences and 3D TSE-SPACE for full-thickness and partial-thickness supraspinatus tendon tears together and for partial-thickness supraspinatus tendon tears alone.

Results

There were 33 full-thickness tears and 28 partial-thickness tears of supraspinatus tendons. For full-thickness and partial-thickness supraspinatus tendon tears together, the mean sensitivity, specificity, and accuracy of both readers were 96, 92, and 94% on 2D sequences and 91, 84, and 89% on 3D TSE-SPACE. For partial-thickness supraspinatus tendon tears alone, the mean sensitivity, specificity, and accuracy were 95, 92, and 94% on 2D sequences and 84, 85, and 84% on 3D TSE-SPACE. There was no statistical difference between 2D sequences and 3D TSE-SPACE. Interobserver agreements were almost perfect on 2D conventional sequences and substantial on 3D TSE-SPACE.

Conclusion

Compared with 2D conventional sequences, MR arthrography using 3D TSE-SPACE was comparable for diagnosing supraspinatus tendon tears despite limitations in detecting small partial-thickness tears and in discriminating between full-thickness and deep partial-thickness tears.     

MR evaluation of subscapularis tears.

PURPOSE: The purpose of this work was to describe the MR appearance of tears of the subscapularis tendon and compare the usefulness of different imaging planes as well as note the association of subscapularis tears with other rotator cuff tears and biceps tendon dislocations. METHOD: MR studies at 1.5 T over an 8 year interval were retrospectively assessed for the presence of a rotator cuff tear and/or tear of the subscapularis tendon. Images that showed a subscapularis tear were reviewed for the presence of a visible tear separately on the axial, coronal, and sagittal images. The MR studies were also evaluated for associated tears of the supraspinatus, infraspinatus, and teres minor muscles as well as biceps tendon dislocation and the "naked humerus sign" on coronal images. Last, clinical records and surgical reports were reviewed. RESULTS: Forty-five (2%) of 2,167 rotator cuff tears involved the subscapularis; 27% were partial and 73% were complete tears. Tears were best seen in the sagittal oblique plane. Almost all subscapularis tears were an extension of typical rotator cuff tears: supraspinatus in 35 patients (79%), extending into infraspinatus tears in 25 (56%) and into teres minor tears in 2 patients (4%). Bicipital dislocations were seen in 22 patients (49%), and three complete tears of the biceps (7%) were noted as well. The naked humerus sign was demonstrated in 31 patients (69%). Surgical reports that confirmed the MR findings were available for 15 patients. CONCLUSION: About 2% of rotator cuff tears involve the subscapularis tendon. Most subscapularis tears are extensions of supraspinatus tears and frequently involve the biceps tendon.     

Diagnosis of tears in rotator-cuff-injuries

Pathology of the rotator cuff is the cause of most common problems at the shoulder joint. Acute injuries are not as frequent as chronic cuff disease, but often they aggravate inflammatory or degenerative tendon alterations, even if they are of minor severity. Traumatic rotator cuff tears predominantly affect the supraspinatus tendon or the rotator interval. The subscapularis tendon is involved in anterior dislocations of the glenohumeral joint or in direct trauma. Plain film radiography still remains the base of all further imaging studies. If only full-thickness tears must be ruled out, double-contrast arthrography and ultrasound are acceptable imaging modalities. However, the former has a drawback in being invasive and does not detect partial tears at the bursal site of the cuff or rotator cuff tendinopathy, whereas the latter heavily depends on the experience of the radiologist and is restricted to the rotator cuff. Nowadays the most comprehensive imaging method is magnetic resonance (MR) imaging. MR imaging enables the detection or exclusion of complete rotator cuff tears with a reasonable accuracy and is also suitable to diagnose further pathologies of the shoulder joint. MR arthrography is valuable in the detection of subtle anatomic details and further improves the differentiation of rotator cuff diseases. Although in comparison MR imaging is still the most expensive imaging method, its high negative predictive value for the diagnosis of complete rotator cuff tears and its reliability evaluating different shoulder joint pathologies make it the preferred imaging modality.