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.     

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.     

Full-thickness tears of the rotator cuff of the shoulder: diagnosis with MR imaging.

The purpose of this study was to describe MR findings in full-thickness tears of the rotator cuff. Of 102 shoulders examined by MR imaging, 31 were found to have a full-thickness tendon tear at arthroscopy/bursoscopy (five shoulders) or open surgery (26 shoulders). All shoulders were imaged in oblique coronal and axial planes. MR images of the 102 shoulders were evaluated for (1) the presence of fluid in the subacromial and subdeltoid bursae; (2) abnormal signal of the supraspinatus, subscapularis, infraspinatus, and teres minor tendons; (3) interruption of tendon continuity and thinning of the tendon; and (4) proximal retraction of the junction of the muscle and tendon. The presence or absence of each finding was determined by consensus of two radiologists, who interpreted the images without knowledge of the surgical findings. Results in those 31 shoulders with proved full-thickness tears were: fluid in the subacromial bursae (29 shoulders), interruption of tendinous continuity (22 shoulders), focally increased signal of the tendon equivalent to that of water (27 shoulders), and musculotendinous retraction (24 shoulders). The finding of subacromial fluid was a sensitive indicator (93%) of a full-thickness tear, and interruption of tendinous continuity was a specific finding (96%) in diagnosing a full-thickness tear. Our experience shows interruption of tendon continuity is the most specific MR finding of full-thickness rotator cuff tears, while subacromial fluid is the most common finding.     

Value of CT bursography in the evaluation of rotator cuff tears

PURPOSE: To describe the technique and assess the value of subacromial CT bursography in patients with partial surface tear of the rotator cuff tendon. MATERIALS AND METHODS: 15 patients with shoulder pain suggestive of tendinopathy or tear of the rotator cuff were evaluated with subacromial CT bursography. RESULTS: Subacromial CT bursography was normal in 4 patients. Partial surface tear was detected in 7 patients [irregularities (n=2), defect (n=2), superficial tear (n=3)]. Full thickness tear was detected in 4 patients. CONCLUSION: The authors described the technique for subacromial CT bursography to visualize partial surface tears of the rotator cuff tendon. This simple and reliable technique could be an alternative to MR imaging, especially when MR evaluation is not possible.     

Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

Purpose To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Materials and methods Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. Results There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Conclusion Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear.     

MR imaging diagnosis of rotator cuff tears

Thirty-one symptomatic patients were studied with MR imaging to evaluate the sensitivity and specificity of shoulder MR in the diagnosis of rotator cuff tears. Correlative studies included arthroscopy in 19 patients and arthrography in 12 patients. Images were obtained on either a 0.5- or 1.5-T Philips superconducting magnet using spin-echo pulse sequences (650-850/30 [TR, TE], 2000/30, 100) with 5-mm slices oriented in an oblique coronal plane perpendicular to the glenohumeral joint. The MR studies were initially interpreted without knowledge of the results of other diagnostic procedures. The MR diagnosis of cuff tear was made when irregularity, discontinuity, and increased signal were identified in the rotator cuff. MR images showed tears in 10 patients (32%) and were negative for tear in 21 patients (68%). MR correlated with arthroscopy and arthrography in 17 of 18 normal patients, in eight of 10 patients with complete tears, and in one of three patients with partial tears. For complete rotator cuff tears, the sensitivity, specificity, and accuracy were 80%, 94%, and 89%, respectively. For all tears (partial and complete), the sensitivity, specificity, and accuracy were 69%, 94%, and 84%, respectively. These data suggest that MR imaging is an accurate procedure for the diagnosis of complete rotator cuff tears. The number of partial tears (three) in this series is too small to evaluate the value of MR imaging in the diagnosis of partial tears.     

肩袖撕裂的肩关节MR造影评价

目的 评价肩关节MR造影对肩袖撕裂的诊断价值。方法 分析32例病人的肩关节MR造影图像,评价内容包括肩袖肌腱、盂唇、肱二头肌长头腱,结果与肩关节镜及肩部开放手术比较。结果 以肩关节镜和手术结果为标准,32例病人包括14例全层撕裂,6例下表面部分撕裂,12例无撕裂。肩关节MR造影判定有无肩袖撕裂的敏感性、特异性和准确性都为100％;诊断全层撕裂的敏感性、特异性和准确性分别为100％、94％和97％。同时,肩关节MR造影还正确诊断了所有的多肌腱撕裂、合并的盂唇异常及肱二头肌长头腱异常。结论 肩关节MR造影可以准确、全面地评价肩袖撕裂。     

MR anatomy of the subcoracoid bursa and the association of subcoracoid effusion with tears of the anterior rotator cuff and the rotator interval

OBJECTIVE: We describe the MR anatomy of the subcoracoid bursa and findings associated with subcoracoid effusion. CONCLUSION: Fluid in the subcoracoid space, revealed on MR imaging of the shoulder, may lie in the subcoracoid bursa or the subscapularis recess (both structures can be distinguished with MR imaging). In our patients, subcoracoid effusions were often associated with anterior rotator cuff tears, including tears of the rotator interval.     

Rim-rent tear of the rotator cuff: a common and easily overlooked partial tear

OBJECTIVE: The purpose of this study was to determine the incidence of rim-rent rotator cuff tears in a population of patients referred for shoulder MRI and to determine the sensitivity of MRI for the detection of these tears. CONCLUSION: Rim-rent tears are a common type of partial-thickness rotator cuff tear, much more commonly present than has been previously reported. In particular, infraspinatus rim-rent tears are more common than previously believed. Rim-rent tears of the infraspinatus tendon and those involving the anterior-most fibers of the supraspinatus tendon are commonly overlooked on MRI, possibly because of failure to appreciate the high incidence of these types of tears and failure to inspect the anterior-most fibers of the rotator cuff.     

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.     

High-field and low-field MR imaging of superior glenoid labral tears and associated tendon injuries

OBJECTIVE: The purpose of this study was to determine the performance characteristics of high-field and low-field MR imaging for the diagnosis of a glenoid superior labral anteroposterior (SLAP) tear. MATERIALS AND METHODS: High-field (n = 46) or low-field (n = 21) MR imaging was performed on 41 patients with SLAP tears and 26 patients with normal superior labra. The superior labrum was classified into one of four types on the basis of patterns of intralabral signal intensity. The relative frequency of rotator cuff tears and long head of the biceps tendinopathy was also assessed. RESULTS: For the diagnosis of SLAP tear, the sensitivity of high-field MR imaging was 90% (95% confidence interval = 74%, 98%), specificity was 63% (35%, 85%), and accuracy was 80% (66%, 91%). The sensitivity of low-field MR imaging was 64% (31%, 89%), specificity was 70% (35%, 93%), and accuracy was 67% (43%, 85%). A branched linear or stellate focus of abnormal intralabral signal intensity was associated with a SLAP tear in 86% of patients. Conversely, two other labral patterns correlated with a normal superior labrum in 71% of patients. Abnormal signal intensity in the biceps tendon was seen in 15% of patients with a SLAP tear. Full-thickness (37%) and partial-thickness (31%) rotator cuff tears were often seen. CONCLUSION: The performance characteristics of high-field MR imaging are superior to those of low-field MR imaging for the diagnosis of a superior labral tear. Rotator cuff tears can be seen in many patients with superior labral tears, but abnormal signal intensity in the biceps tendon is uncommon.     

Intramuscular rotator cuff cysts: association with tendon tears on MRI and arthroscopy

OBJECTIVE: This study was designed to explore the relationship between intramuscular cysts and rotator cuff tendon tears. CONCLUSION: Intramuscular cysts are strongly associated with rotator cuff tendon tears. Identification of such a cyst should prompt a search for a rotator cuff tear. Findings on MR arthrography and surgery suggest that a delaminating component of the rotator cuff tear may lead to the development of these cysts and may explain the occasional discrepancy between location of tears and location of cysts.     

Ultrasonography of symptomatic rotator cuff tears compared with MR imaging and surgery

Purpose

To compare the accuracy of ultrasonography and magnetic resonance imaging in the detection of rotator cuff tears.

Materials and methods

Ninety-six patients with clinically suspected rotator cuff pathology underwent ultrasonography and magnetic resonance imaging of the shoulder. The findings in 88 patients were compared with arthroscopy or open surgery.

Results

Full-thickness tear was confirmed in 57 cases, partial-thickness tear in 30 cases and degenerative changes without tear in 1. In all 57 cases of full-thickness tear and in 28 out of 30 cases of partial-thickness tear the supraspinatus tendon was involved. The accuracy in the detection of full-thickness tears was 98 and 100% for ultrasonography and magnetic resonance imaging, respectively. The accuracy in the detection of bursal or articular partial-thickness tears was 87 and 90% for ultrasonography and magnetic resonance imaging, respectively.

Conclusions

In experienced hands ultrasonography should be considered as an accurate modality for the initial investigation of rotator cuff, especially supraspinatus, tears.     

Trabecular microstructure and surface changes in the greater tuberosity in rotator cuff tears

OBJECTIVE: When planning surgery in patients with rotator cuff tear, strength of bone at the tendon insertion and trabecular bone structure in the greater tuberosity are usually taken into consideration. We investigated radiographic changes in bone structure of the greater tuberosity in rotator cuff tears. DESIGN: Twenty-two human cadaveric shoulders from subjects ranging from 55 to 75 years of age were obtained. The integrity of the rotator cuff was examined by sonography to determine if it is intact without any tear, or torn partially or completely. The humeral head was sectioned in 3 mm thick coronal slab sections and microradiographed. After digitization of the microradiographs and imaging processing with in-house semi-automated image processing software tools developed using software interfaces on a Sun workstation, the trabecular histomorphometrical structural parameters and connectivity in the greater tuberosity were quantified. The degenerative changes on the surface of the greater tuberosity were interpreted blindly by 2 independent readers. RESULTS: Among the 22 shoulder specimens, the rotator cuff was found intact in 10 shoulders, partially in 7 and fully torn in 5. Statistically significant loss in apparent trabecular bone volume fraction, number of trabecular nodes, and number of trabecular branches, and a statistically significant increase in apparent trabecular separation and number of trabecular free ends were found in the greater tuberosity of the shoulders with tears. The loss was greater in association with full tear than in partial tear. Thickening of the cortical margin of the enthesis, irregularity of its surface, and calcification beyond the tidemark were observed in 2 (20%) shoulders with intact rotator cuff, in 6 (86%) shoulders with partial tear, and in 5 (100%) shoulders with full tear. CONCLUSIONS: Rotator cuff tears are associated with degenerative changes on the bone surface and with disuse osteopenia of the greater tuberosity. Aging, degenerative enthesopathy of the supraspinatus tendon, and rotator cuff tears appear closely related.     

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.     

Surgically repaired massive rotator cuff tears: MRI of tendon integrity, muscle fatty degeneration, and muscle atrophy correlated with intraoperative and clinical findings

OBJECTIVE: Our goal in this study was to evaluate by means of MRI the clinical significance of tendon integrity, muscle fatty degeneration, and muscle atrophy in surgically repaired massive rotator cuff tears and to correlate these and other prognostic factors with intraoperative and clinical findings. MATERIALS AND METHODS: Twenty-eight surgically proven massive rotator cuff tears were retrospectively included in the study. Twenty-two patients underwent complete repair, and six patients underwent partial repair. Preoperative and postoperative clinical assessment was performed by using the University of California at Los Angeles score. Preoperative and postoperative MRI studies were evaluated for the presence and extent of rotator cuff tear and for the degree of fatty degeneration and atrophy of the rotator cuff muscles. RESULTS: At a mean 44.4 months' follow-up, 20 patients (71.4%) had a favorable result. A total of 25 patients (89.2%) showed postoperative full-thickness rotator cuff tear, 19 of which were reruptures. A sagittal preoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 100% for predicting a favorable outcome. A coronal postoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 85.7% and a positive predictive value of 92.9% for predicting a favorable outcome. A postoperative fatty degeneration of infraspinatus muscle less than or equal to 2 had a specificity of 87.5% and a positive predictive value of 90.9% for predicting a favorable outcome. CONCLUSION: Open repair of massive rotator cuff tears may reach a favorable outcome in a significant proportion of patients, despite a high rate of recurrent or residual tears. Oblique coronal sizes of the recurrent or residual tear of less than or equal to 34 mm and postoperative fatty degenerations of infraspinatus muscle of less than or equal to 2 may allow a favorable outcome.     

Clinical impact of MR arthrography of the shoulder.

PURPOSE: To evaluate the effect of MR arthrography of the shoulder on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons. MATERIAL AND METHODS: Orthopedic surgeons completed a questionnaire before and after MR arthrography for 73 consecutive patients. The main indications were suspected rotator cuff abnormalities. The clinical diagnosis, the degree of confidence in this diagnosis, and the therapeutic decision were noted before and after MR imaging. Surgical reports were available for 34 patients. RESULTS: Thirty-four percent of the pre-MR imaging diagnoses were withdrawn after MR imaging, and new diagnoses were made after MR imaging in 13% of the cases. Confidence in the diagnosis increased significantly after MR imaging for supraspinatus and infraspinatus lesions (p<0.05). Changes of therapeutic decision after MR imaging were noted in 36 of the 73 patients (49%). In 23 patients, more invasive therapeutic procedures were initiated after MR imaging, and a more conservative treatment was implemented for 13 patients. Agreement of MR diagnoses with surgery was 94% for supraspinatus tears, 87% for infraspinatus tears, 77% for subscapularis tears, and 81% for biceps tendon lesions. Agreement of clinical diagnoses with surgery was 56%, 83%, 50%, and 64%, respectively. CONCLUSION: MR arthrography of the shoulder has a major effect on diagnostic thinking and therapeutic decisions by orthopedic shoulder surgeons.     

Findings of the subcoracoid bursa on MR arthrography and their clinical significance

We studied visualization of the subcoracoid bursa by conducting a retrospective analysis of the MR arthrograms of 101 shoulders with surgical confirmation. MR arthrography showed the subcoracoid bursa in 28 shoulders, among which the bursa was revealed by inadvertent direct injection of contrast material into the bursa in 10 shoulders. Of the remaining 18 shoulders, 16 shoulders had rotator cuff tears, one had shoulder instability, and one had dislocation of the long head of the biceps tendon. Both the subcoracoid and subscapularis bursae are located in the subcoracoid space. The subcoracoid bursa does not communicate with the subscapularis bursa, but occasionally communicates with the subacromial-subdeltoid bursa. On MR arthrography, contrast material in the subcoracoid bursa indicates a pathologic condition such as rotator cuff tear. Careful examination of the subcoracoid bursa on MR arthrography helps to achieve better assessment of the rotator cuff.     

Sonographic detection of rotator cuff tears

Thirty-nine consecutive patients referred for shoulder arthrography underwent shoulder sonography to determine the ability of sonography to detect rotator cuff tears. Fifteen patients had arthrographically proven rotator cuff tears. Of these, 14 were detected by sonography, for a sensitivity of 93%. The three sonographic criteria indicative of rotator cuff tear were (1) discontinuity in the normal homogeneous echogenicity of the rotator cuff; (2) replacement of the normal homogeneous echogenicity by a central echogenic band; and (3) nonvisualization of the cuff. Twenty patients had normal sonographic examinations, 19 of which were normal by arthrography. Therefore, the predictive value of a negative sonogram was 95%. On the basis of these findings, sonography can provide a noninvasive means of screening patients with suspected rotator cuff tears.