The coracoacromial arch: MR evaluation and correlation with rotator cuff pathology

The relative prevalence of various acromial shapes, appearance of the coracoacromial ligament and enthesophytes along the inferior aspect of the acromioclavicular joint in patients with and without rotator cuff tears were evaluated. Of 76 patients with clinical instability and impingement, 31 had a normal rotator cuff and 45 demonstrated a partial or full tear of the supraspinatus tendon at surgery. Results were compared with those from magnetic resonance (MR) scans of 57 asymptomatic volunteers. Of the 45 patients with a supraspinatus tear, 38% (17) had a flat acromial undersurface (type I), 40% (18) had a concave acromial undersurface (type II), 18% (8) had an anteriorly hooked acromion (type III), and 4% (2) had an inferiorly convex acromion (type IV). Among the 31 patients with a normal rotator cuff at surgery and the 57 asymptomatic volunteers, the respective prevalences of the type I acromion were 39% (12) and 44% (25), of type II 48% (15) and 35% (20), type III 3% (1) and 12% (7), and type IV 10% (3) and 9% (5). Shoulders with surgically proven rotator cuff tears showed a tendential association with a type III acromion (8/45) and statistically significant associations with a thickened coracoacromial ligament (17/45) and acromioclavicular enthesophytes (18/45). For the association between inferiorly directed acromioclavicular joint enthesophytes and rotator cuff tears, age appears to be a confounding factor. The type IV acromion, newly classified by this study, does not have a recognizable association with rotator cuff tears. Assessment of the osseous-ligamentous coracoacromial outlet by may prove helpful to the orthopedic surgeon in patients for whom surgical decompression is contemplated.     

MR arthrography of partial thickness tears of the undersurface of the rotator cuff: an arthroscopic correlation

Objective Partial thickness tears of the undersurface (articular surface) of the rotator cuff (RTC) have been recognized increasingly in recent years as a source of treatable shoulder pain in the athletic population. This study evaluated the efficacy of MR arthrography (MR-ARTH) in diagnosing these tears.Design and patients The study design was a retrospective review of medical records of patients who had presented with refractory shoulder complaints and subsequently undergone MR arthrography with multiple signal MRI sequences followed by shoulder arthroscopy. Of particular interest were patients who had oblique T1 fat suppression (COT1FS), coronal oblique T2 (COT2), and coronal oblique T2 fat suppression (COT2FS) images taken. Seventy-six subjects met the study criteria. Investigators examined the MR-ARTH images from these patients' charts while blinded as to arthroscopic results, clinical signs and symptoms.Results Based on COT1FS images, investigators identified nine subjects as having had full thickness tears, 28 as having had partial thickness tears of the undersurface of the rotator cuff (PRTC), and 39 as having had intact RTC. These results were compared to actual findings at arthroscopy: nine full thickness tears, 26 of 28 with PRTC and 34 of 39 intact. The sensitivity of MR-ARTH was 84%, with a positive predictive value of 93%. The overall accuracy was 91% (69/76). The specificity was 96%. That is, if a PRTC was not seen on the MR-ARTH images, it was very unlikely to exist. COT2 and COT2FS sequences failed to increase sensitivity and overall efficacy of MRI.Conclusion PRTC can be diagnosed accurately by MR-ARTH with gadopentatate contrast. A COT1FS sequence is recommended for evaluation when tears are suspected.     

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.     

Indirect MR arthrography of the shoulder in detection of rotator cuff ruptures

The aim of this study was to compare the efficacy of indirect MR arthrography images obtained following intravenous contrast injection and conventional MR imaging in the diagnosis of rotator cuff tears. Twenty-four patients with clinically suspected rotator cuff disease were examined. Conventional MR images and post-contrast indirect MR arthrography images were obtained. All images were evaluated in a blinded fashion by two musculoskeletal radiologist. Results were than analyzed depending on surgical output. The correlation coefficient (Spearman rank correlation test) and the kappa values for agreement between surgery and imaging techniques were calculated. The correlation coefficients between indirect MR arthrography and surgery for reader 1 and reader 2 were 0.9137 and 0.9773, respectively. Whereas the agreement between conventional MR imaging and surgery was moderate (ϰ = 0.383–0.571), the agreement between indirect MR arthrography and surgery was excellent (ϰ = 0.873–0.936). We suggest the use of indirect MR arthrography technique when conventional MR images are equivocal in diagnosis of rotator cuff disease. Received: 12 April 2000/Revised: 22 May 2000/Accepted: 23 May 2000     

Fast MR arthrography using VIBE sequences to evaluate the rotator cuff

Purpose  The purpose of this paper was to evaluate if short volumetric interpolated breath-hold examination (VIBE) sequences can be used as a substitute for T1-weighted with fat saturation (T1-FS) sequences when performing magnetic resonance (MR) arthrography to diagnose rotator cuff tears. Materials and methods  Eighty-two patients underwent direct MR arthrography of the shoulder joint using VIBE (acquisition time of 13 s) and T1-FS (acquisition time of 5 min) sequences in the axial and paracoronal plane on a 1.0-T MR unit. Two radiologists scored rotator cuff tendons on VIBE and T1-FS images separately as normal, small/large partial thickness and full thickness tears with or without geyser sign. T1-FS sequences were considered the gold standard. Surgical correlation was available in a small sample. Results  Sensitivity, specificity, and positive and negative predictive values of VIBE were greater than 92% for large articular-sided partial thickness and full thickness tears. For detecting fraying and articular-sided small partial thickness tears, these parameters were 55%, 94%, 94%, and 57%, respectively. The simple kappa value was 0.76, and the weighted kappa value was 0.86 for agreement between T1-FS and VIBE scores. All large partial and full thickness tears at surgery were correctly diagnosed using VIBE or T1-FS MR images. Conclusion  Fast MR arthrography of the shoulder joint using VIBE sequences showed good concordance with the classically used T1-FS sequences for the appearance of the rotator cuff, in particular for large articular-sided partial thickness tears and for full thickness tears. Due to its very short acquisition time, VIBE may be especially useful when performing MR arthrography in claustrophobic patients or patients with a painful shoulder.     

Coexistence of calcific tendinitis and rotator cuff tear: an arthrographic study

A prospective evaluation of the coexistence of calcific tendinitis and tear of the rotator cuff demonstrated by arthrography was made in patients presenting with shoulder pain. Patients were X-rayed using conventional views and impingement views. Eighty-one patients (mean age 61.2 years) with calcific tendinitis underwent arthrography. Arthrography showed 22 partial or complete tears of the rotator cuff. A small rather than a large amount of calcification was more likely to be associated with a rotator cuff tear (p = 0.005). The coexistence of calcific tendinitis with rotator cuff tear is not uncommon, especially in older age groups.     

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.     

Imaging of the rotator cuff: an arthrographic pitfall

We present a case where MRI and arthrography of the shoulder reports provided seemingly conflicting data. The subsequent findings at arthroscopy revealed a potential pitfall in arthrographic interpretation. Received 1 July 1997; Revision received 12 September 1997; Accepted 16 September 1997     

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.     

MRI和MR关节腔造影诊断肩袖撕裂的实验研究

目的 :探讨常规MRI和MR肩关节腔造影诊断肩袖撕裂的价值。方法 :采用 2 0个人离体肩关节标本 ,将常规MRI和追加MR肩关节腔造影检查结果与大体解剖、组织病理学结果进行比较。结果 :常规MRI检出肩袖部分撕裂的敏感度约为 61.9% ,追加MR肩关节腔造影后敏感度提高到 90 .5 %。常规MRI和MR关节腔造影检出肩袖完全撕裂的敏感度和特异度均为 10 0 %和 97.1%。结论 :在常规MRI检查的基础上追加MRI关节腔造影能提高检出肩袖部分撕裂的敏感度。     

Diagnosis of partial and complete rotator cuff tears using combined gradient echo and spin echo imaging

Most magnetic resonance (MR) studies evaluating the rotator cuff for tears have used T2-weighted imaging in the coronal oblique and sagittal oblique planes, T2^*-weighted gradient echo imaging, however, has advantages over spin echo imaging, including contiguous slices without cross-talk, high contrast around the cuff, and intrinsically shorter imaging times which can be used to increase the number of signals averaged and thus improve the signal-to-noise ratio. We reviewed the shoulder MR scans of 87 consecutive patients who underwent both a MR scan and a shoulder arthroscopy during which the size of tears, if present, was graded. The reviewers were blinded as to the history and arthroscopic results. The MR scans included oblique coronal T2^*-weighted gradient echo and oblique sagittal T2-weighted spin echo images. MR cuff grades were correlated with arthroscopic findings. For complete tears, the sensitivity of MR was 0.91 and the specificity 0.95. For partial tears, the sensitivity was 0.74 and the specificity 0.87. This accuracy is similar to two-plane T2-weighted imaging as previously reported in the literature. There was a statistically significant correlation (p < 0.0005) between the cuff grade as determined by MR and the arthroscopic findings.     

Low-field MR arthrography of the shoulder joint: technique,indications, and clinical results

In the age of cost containment and urgent reductions in health care expenditures, new options have to be explored to satisfy both diagnostic requirements and economic limitations. The introduction of low-field MR systems for assessment of joint disorders seemed to be an option for lower costs. The purpose of this article is to summarize available experiences with low-field MR arthrography of the glenohumeral joint with respect to image quality and diagnostic accuracy in detecting labral and rotator cuff lesions. Up to now, there has been only a limited number of studies available dealing with low-field MR arthrography of the glenohumeral joint. They reveal that, despite a minor image quality in comparison with high-field imaging, low-field MR arthrography of the shoulder allows for sufficient evaluation of intra- and extra-articular structures in the detection of major abnormalities such as glenohumeral instability or rotator cuff disease. Furthermore, open-configured MR scanners enable kinematic studies: Besides the analysis of normal motion, pathological findings in patients with instabilities and impingement syndrome can be delineated. They further offer the possibility for performing MR imaging-guided arthrography of the shoulder. This was first described using an open C-arm scanner with a vertically oriented magnetic field so that MR arthrography may be performed in one setting. Electronic Publication     

Comparisons of the Various Partial-Thickness Rotator Cuff Tears on MR Arthrography and Arthroscopic Correlation

Objective

To assess the diagnostic performance of MR arthrography in the diagnosis of the various types of partial-thickness rotator cuff tears by comparing the MR imaging findings with the arthroscopic findings.

Materials and Methods

The series of MR arthrography studies included 202 patients consisting of 100 patients with partial-thickness rotator cuff tears proved by arthroscopy and a control group of 102 patients with arthroscopically intact rotator cuffs, which were reviewed in random order. At arthroscopy, 54 articular-sided, 26 bursal-sided, 20 both articular- and bursal-sided partial-thickness tears were diagnosed. The MR arthrographies were analyzed by two radiologists for articular-sided tears, bursal-sided tears, and both articular- and bursal-sided tears of the rotator cuff. The sensitivity and specificity of each type of partial-thickness tears were determined. Kappa statistics was calculated to determine the inter- and intra-observer agreement of the diagnosis of partial-thickness rotator cuff tears.

Results

The sensitivity and specificity of the various types of rotator cuff tears were 85% and 90%, respectively for articular-sided tears, 62% and 95% for bursal-sided tears, as well as 45% and 99% for both articular- and bursal-sided tears. False-negative assessments were primarily observed in the diagnosis of bursal-sided tears. Conversely, both articular- and bursal-sided tears were overestimated as full-thickness tears. Inter-observer agreement was excellent for the diagnosis of articular-sided tears (k = 0.70), moderate (k = 0.59) for bursal-sided tears, and fair (k = 0.34) for both articular- and bursal-sided tears, respectively. Intra-observer agreement for the interpretation of articular- and bursal-sided tears was excellent and good, respectively, whereas intra-observer agreement for both articular- and bursal-sided tears was moderate.

Conclusion

MR arthrography is a useful diagnostic tool for partial-thickness rotator cuff tears, but has limitations in that it has low sensitivity in bursal- and both articular- and bursal-sided tears. In addition, it shows only fair inter-observer agreement when it comes to predicting both articular- and bursal-sided tears.     

Limited sensitivity of ultrasound for the detection of rotator cuff tears

Bilateral rotator cuff sonography was performed on 56 patients referred for shoulder arthrography to detect rotator cuff tears. Since one patient had bilateral arthrography there were 57 arthrograms. Twenty-seven shoulders had rotator cuff tears shown on arthrography, 15 of which were detected by sonography. Eleven were false negative by sonography, and one was indeterminate. Of the 30 shoulders with negative arthrograms, 28 had normal sonograms and two were false positive. Sensitivity was 58%, specificity was 93% and overall accuracy was 77%. The positive and negative predictive values were 88% and 72%. These results suggest that sonography has limited value in screening patients for rotator cuff tears and that a positive sonographic reading is more reliable than a negative one. Theories relating to the variable anatomic configuration of a tear are postulated to explain these results, which differ from those previously reported.     

超声诊断肩袖撕裂的临床指导价值研究

目的：探讨肩袖撕裂的超声特征,评价超声检查肩袖撕裂的应用价值及对临床治疗的指导意义。方法：对临床怀疑有肩袖损伤的66例患者（70个肩关节）进行超声检查,并与手术、肩关节造影或磁共振结果进行比较。结果：肩袖撕裂的主要超声表现为：肩袖内局灶性异常回声,肩袖部分缺失,肩袖不显示。超声诊断的敏感性为98%（54/55）,特异性为81%（17/21）,准确性为93%（65/70）。结论：超声诊断肩袖撕裂有很高的应用价值,对临床治疗有很好的指导意义。     

Evaluation of the rotator cuff and glenoid labrum using a 0.2-Tesla extremity magnetic resonance (MR) system: MR results compared to surgical findings.

The purpose of this investigation was to evaluate the diagnostic capabilities of magnetic resonance imaging (MRI) performed using a dedicated-extremity MR system in detecting lesions of the rotator cuff and glenoid labrum. This retrospective study compared the MR results obtained in 47 patients that underwent MRI using a 0.2-Tesla extremity MR system (E-scan) to the surgical findings. MR images of the shoulder were obtained as follows: shoulder coil, T1-weighted, coronal-oblique and axial images; short Tau inversion recovery (STIR), coronal-oblique images; and T2-weighted, coronal-oblique, sagittal-oblique, and axial images. The MR examinations were interpreted by three highly experienced, musculoskeletal radiologists. Open surgical (N = 26) or arthroscopic (N = 21) procedures were performed within a mean time of 33 days after MRI. The surgical findings revealed rotator cuff tears in 28 patients and labral lesions in 9 patients. For the rotator cuff tears, the sensitivity, specificity, positive predictive value, and negative predictive value were 89%, 100%, 100%, and 90%, respectively. For the labral lesions, the sensitivity, specificity, positive predictive value, and negative predictive value were 89%, 95%, 80%, and 97%, respectively. The findings indicated that there was good agreement comparing the MR results obtained using the low-field extremity MR system to the surgical findings for determination of lesions of the rotator cuff and glenoid labrum. Notably, the statistical values determined for the use of this MR system were comparable to those reported in the peer-reviewed literature for the use of whole-body, mid- and high-field-strength MR systems.     

Anterior versus posterior, and rim-rent rotator cuff tears: prevalence and MR sensitivity

Purpose. To determine the relative distribution of the locations of rotator cuff tears, and the sensitivity of anterior versus posterior tears on MR images. Patients and methods. We identified 110 consecutive patients who had a shoulder MR and either a partial-thickness or a small full-thickness rotator cuff tear diagnosed at arthroscopy. From the arthroscopy videotapes, we classified the tears as centered in the anterior or posterior half of the cuff, and as either in the critical zone or adjacent to the bony insertion. The original MR interpretation was compared with the arthroscopic findings. MR sensitivity and patient age were compared between patients with tears in the anterior and posterior halves of the cuff. In addition, in patients with partial tears less than 2 cm in diameter, an age comparison between those with tears in the critical zone and those with articular surface tears adjacent to the bony insertion (rim-rent tear) was performed. Results. The tear was centered in the anterior half of the rotator cuff in 79% of the patients younger than 36 years old, and in 89% of the patients 36 years old and over. The average age of the patients with tears in the anterior half (44 years) was not significantly different from the average age of those with posterior tears (40 years)(P=0.23). The sensitivity of MR for anterior tears was 0.69, and for posterior tears it was 0.56 (P=0.17). The average age of the 9 patients with rim-rent tears was 31 years, while that of the 28 patients with similarly-sized partial tears not involving the insertion was 40 years old (P=0.048). Five of the nine rim-rent tears (0.56) were interpreted correctly on the original MR report; two of the other tears were misinterpreted as intratendinous fluid but were diagnosable in retrospect. Conclusion. Even in patients less than 36 years old, most partial and small full-thickness rotator cuff tears are centered in the anterior half of the supraspinatus. Although our figure for MR sensitivity for these tears is lower than in recent articles, we found no significant difference between the sensitivity of MR for diagnosing posterior tears versus tears in the anterior half of the supraspinatus tendon. Rim-rent tears can be mistaken for intratendinous signal, and should be carefully looked for in younger patients with shoulder pain.     

Ultrasonography for diagnosis of rotator cuff tear

 In this study the clinical usefulness of ultrasonography in the diagnosis of rotator cuff tears was assessed. One hundred twenty-two patients undergoing preoperative ultrasonography were evaluated surgically. Three different ultrasonographic machines were applied with a 7.5-MHz linear-array transducer. Surgery confirmed a sensitivity of 79% for full-thickness tears and 50% for partial thickness tears. In 73 patients with negative ultrasonographic findings, the specifity was 100% for full-thickness tears and 90% for partial-thickness tears. The diagnostic sensitivity for full-thickness tears of the Hitachi EUB-340 system was significantly lower than those of Hitachi EUB-415 and EUB-515, and thus the former cannot be recommended for detection of rotator cuff tears. The sensitivity with regard to partial-thickness tears was also significantly lower with the Hitachi EUB-340 system as compared to the Hitachi EUB-515. There were no significant differences in false-positive rate among the three machines used. In conclusion, accurate ultrasonographic diagnosis of rotator cuff tear requires a high-resolution machine, as well as considerable experience in interpretation.     

Assessment of the rotator cuff and glenoid labrum using an extremity MR system: MR results compared to surgical findings from a multi-center study

PURPOSE: To conduct a multi-center assessment of the use of a 0.2-T, extremity MR system (E-scan; General Electric Lunar Corp. and Esaote, Genoa, Italy) for identifying tears of the rotator cuff and glenoid labrum. MATERIALS AND METHODS: A retrospective study was performed involving 160 patients (age range, 15-84 years old) from five facilities in the United States, comparing shoulder MR imaging to surgical findings. MR imaging of the shoulder was conducted as follows: shoulder coil; T1-weighted spin echo, coronal-oblique and axial images; short Tau inversion recovery (STIR), coronal-oblique images and axial images; and T2-weighted spin echo, coronal-oblique and sagittal-oblique images. The MR examinations were interpreted in an independent, prospective manner by two radiologists with extensive musculoskeletal MRI experience. Arthroscopic (N = 103) or open surgical (N = 57) procedures were performed within a mean of 53 days after MR imaging. RESULTS: Surgical findings demonstrated rotator cuff tears in 131 patients and labral tears in 60 patients. For the rotator cuff, the sensitivity, specificity, positive predictive value, and negative predictive value were 90%, 93%, 98%, and 68%, respectively. For the labrum, the sensitivity, specificity, positive predictive value, and negative predictive value were 55%, 100%, 100%, and 82%, respectively. CONCLUSIONS: There was good agreement when MR results obtained using the extremity MR system were compared to surgical findings for identifying rotator cuff tears, while the sensitivity of MR imaging for determining labral tears was relatively poor. Nevertheless, these findings were comparable to those reported in the peer-reviewed literature for MR systems operating at mid-, and high-field-strengths.