MRI of the shoulder

Shoulder imaging is one of the major applications in musculoskeletal MRI. In order to analyze the images it is important to keep informed about anatomical and pathological findings and publications. In this article MRI technique, anatomy and pathology is reviewed. Technical considerations about MR sequences and examination strategy are only shortly discussed with emphasis on turbo spin echo and short T1 inversion recovery imaging. Basic anatomy as well as recent findings, including macroscopic aspects of the supraspinatus fat pad, composition of the supraspinatus muscle belly, and variability of the glenohumeral ligaments or coracoid ligament, are presented. Basic pathological conditions are described in detail, e. g. instability particularly problems in differentiating the various subtypes of labral pathology. Rotator cuff diseases are elucidated with emphasis on some rarer entities such as subscapularis calcifying tendinitis, coracoid impingement, chronic bursitis producing the double-line sign, prominent coraco-acromial ligament and the impingement due to an inflamed os acromiale.     

MRI of the shoulder

Magnetic resonance imaging of the shoulder is routinely used, especially in the evaluation of rotator cuff disease and glenohumeral instability. More recent studies have provided a more sophisticated understanding of what represents a pathologic rotator cuff. Similarly, there has been an increased focus on the role of the glenohumeral ligaments and their labral attachment sites in maintaining glenohumeral stability. There have been technical advances as well, including the increased use of magnetic resonance arthrography. In addition, newer studies have shed light on the pathophysiology of the long bicipital tendon and compression neuropathies involving the suprascapular and axillary nerves.     

MRI of shoulder instability

The most unstable joint in the body, the glenohumeral joint is subject to many insults including microinstability, subluxation and dislocation. During the last two decades, MRI has allowed for direct visualization of many of the lesions related to instability, aiding in diagnosis as well as therapeutic planning and follow-up. This article reviews the use of MRI for shoulder instability and describes the different types of lesions associated with this disorder. Topics include technical considerations, the use of MR arthrography, normal anatomy and variants, labral and glenohumeral ligament pathology, and osseous lesions related to instability.     

Postoperative MRI of the shoulder

Magnetic resonance imaging (MRI) evaluation of the postoperative shoulder presents technical and diagnostic challenges related to imaging artifacts from hardware and micrometallic shavings, postsurgical scarring, and morphological alterations. Improved visualization of postoperative shoulder anatomy and pathology can be obtained with the use of metal artifact reduction techniques as well as MR arthrography. In this article we review the MR techniques that are designed to address these technical and diagnostic challenges, and we discuss the definitions and indications, normal MRI appearance, and complications of routine surgical procedures for treatment of injuries to the rotator cuff, labral ligamentous complex, and biceps tendon. J. Magn. Reson. Imaging 2014;40:1280–1297 . © 2014 Wiley Periodicals, Inc .     

MRI of Little Leaguer's shoulder

The MRI appearance of 'Little Leaguer's shoulder' has not been previously reported in the radiology literature. Purported etiologies include proximal humeral epiphyseolysis, osteochondrosis of the proximal humeral epiphysis, stress fracture of the proximal humeral epiphyseal plate, and rotational stress fracture of the proximal humeral epiphyseal plate. We describe magnetic resonance imaging findings in four patients and review the literature.     

MRI of the postoperative shoulder

Pain in the postoperative shoulder is difficult for all individuals involved. The patient has already undergone a surgical procedure and is presenting now with pain possibly relating to a complication of the procedure or reinjury. In addition, the patient typically has undergone a series of maneuvers, from physical therapy to cortisone injection, without relief of the symptoms. For the orthopaedic surgeon the possibility of a complication of the procedure is disheartening. Finally, for the radiologist the postoperative shoulder usually is more difficult to interpret because of a change in the normal anatomy, not knowing exactly what was accomplished at surgery or what techniques or types of equipment were used, and, more typically, the presence of artifact.     

MRI of the postoperative shoulder

Performing and interpreting MRI of the shoulder in patients after surgery is a difficult task. The normal anatomic features are distorted by the surgical alterations as well as the artifacts that result from metal and other materials used in the surgical procedures. This article reviews the common surgical procedures undertaken in patients with rotator cuff disease and shoulder instability, and how they affect the appearance of the relevant anatomic structures on MRI examination. It also reviews the more common causes for residual and recurrent abnormalities seen in such patients and how MRI can be used to diagnose such lesions, thus aiding the orthopedic surgeon in treating these difficult clinical problems.     

MRI and sonography of the shoulder

We prospectively evaluated the diagnostic value of sonography and magnetic resonance imaging (MRI) in 24 shoulders in 23 patients with suspected rotator cuff tears using arthrography as gold standard. Sonography demonstrated 14 of 15, MRI 10 of 15 rotator cuff tears, respectively. Sonography diagnosed seven of nine intact rotator cuffs correctly, MRI eight of nine. In a retrospective study we reviewed the diagnostic value of sonography and MRI in other pathologies of the shoulder including intra-articular pathology, humeral head and acromioclavicular joint pathology, and calcification. We conclude that with regard to cost and patient compliance, sonography should be the first radiologic examination in suspected rotator cuff tears if performed by an experienced sonographer. MRI is superior in depicting additional pathology and is less operator dependent. It may thus become the method of choice for the evaluation of the rotator cuff and related pathology in the future.     

MRI assessment of pelvic trauma

This article details the utility of magnetic resonance imaging (MRI) in assessing patients with pelvic pain resulting from musculoskeletal trauma and its differential diagnoses. There are numerous pathologies seen in and around the pelvis that frequently present with a confusing clinical picture. The anatomy is complex, with imaging assessment difficult. There is substantial overlap between conditions, and knowledge of a wide spectrum of disease is needed to successfully interpret pelvic MRI.     

MRI of acute spinal trauma

The clinician managing patients who have suffered trauma to the spine requires several questions answered from imaging studies. In the acute stage, a full assessment of the complete injury to the bony, ligamentous, disc and neural tissues will determine the stability of the injury and help decide the nature of clinical management, either conservative or surgical, and also help in determining the surgical approach. Magnetic resonance imaging (MRI) is established as a vital imaging technique and can answer many of the questions posed above. The purpose of this article is to review the current status of MRI in the assessment of acute spinal trauma. Received: 24 August 2000 Revision requested: 13 December 2000 Revision received: 31 January 2001 Accepted: 15 February 2001     

MRI of internal impingement of the shoulder

OBJECTIVE: Internal impingement is a condition that occurs in athletes in which the shoulder is put in extreme abduction and external rotation during overhead movements. During this motion, the posterior fibers of the supraspinatus tendon, anterior fibers of the infraspinatus tendon, or both can get impinged between the humeral head and the posterior glenoid. The purpose of this study was to evaluate the ability of MRI to show the findings of internal impingement of the shoulder. CONCLUSION: As opposed to our six patients with clinically and surgically diagnosed internal impingement, the control patients had isolated pathology in the rotator cuff, labrum, or humeral head. We found that the constellation of findings of undersurface tears of the supraspinatus or infraspinatus tendon and cystic changes in the posterior aspect of the humeral head associated with posterosuperior labral pathology is a consistent finding diagnostic of internal impingement.     

Kinematic shoulder MRI: the diagnostic value in acute shoulder dislocations

Objectives

To determine whether positioning of the arm in adduction and internal rotation would improve the confidence in the diagnosis of Bankart lesions in first time shoulder dislocators.

Methods

Eleven patients were imaged on an open bore MRI within 1–6 days of traumatic shoulder dislocation with the arm adducted and internally rotated, and subsequently the patients were reimaged with the arm adduced and externally rotated. Two blinded musculoskeletal radiologists determined the confidence of diagnosing labral tears in each of the two positions.

Results

An anterior–inferior labral tear was diagnosed in 11/11 patients in internal rotation and in 6/11 patients in external rotation. The average confidence was 2.8 in internal rotation and 1.5 in external rotation (on a scale of 0–3). Using a Wilcoxon signed rank test, the certainty of the diagnosis was determined to be significantly higher with the arm in internal rotation (P?=?0.016).

Conclusions

MRI performed with the arm in internal rotation for patients with acute first time anterior shoulder dislocation increases the certainty of the diagnosis of anterior–inferior labral tears.

Key Points

? Adduction and internal arm rotation improves the MRI diagnosis of Bankart tears. ? Arm positioning in ADIR has distinct advantages over abduction and external rotation. ? Early imaging after shoulder dislocation may provide a diagnostically useful “arthrographic” effect.     

MR evaluation of synovial injury in shoulder trauma

The purpose of this study was to determine magnetic resonance imaging (MRI) findings relevant to synovial injury of the shoulder in patients with and without acute shoulder trauma. Three hundred and nine consecutive shoulder MRI studies (185—male, 124—female, 50 ± 15 years old) were retrospectively evaluated for findings suggestive of synovial injury including rupture and/or diverticulum of the joint capsule, bursa, and biceps tendon sheath (BTS), ganglion/synovial cyst, geyser phenomenon, and sequel of previous shoulder dislocation (Hill–Sachs deformity). Patients with one or more of these findings were included in the MR-positive group, whereas the remaining subjects were used as MR negatives. Based on their medical records, patients were also divided into trauma and non-trauma groups, and statistical analysis was performed to evaluate the association between the aforementioned MRI findings and history of shoulder trauma. Fifty-six patients were included in the MR-positive group and 253 in the MR-negative group. In MR-positive group, the incidence of capsular rupture (CR) and subacromial/subdeltoid (SASD) bursal rupture was higher in trauma patients, whereas the incidence of BTS diverticulum and ganglion cyst was higher in subjects without trauma. Significant association was found between the history of acute trauma and CR, SASD bursal rupture, BTS rupture, and Hill–Sachs deformity. In shoulder MR examination, presence of CR and/or SASD bursal rupture is strongly suggestive of acute shoulder trauma. In addition, BTS rupture and Hill–Sachs deformity are more prevalent in patients with acute shoulder trauma. The presence of these features should alert MRI readers to assess for additional trauma-related internal derangements, if a respective history has not been provided.     

跟腱损伤的MRI诊断

目的:评价跟腱损伤的MRI诊断价值。方法:回顾11例有明确踝关节损伤史、经手术证实为跟腱损伤患者的MRI表现,并与手术结果对照。结果:11例MRI均有异常表现,诊断为跟腱完全断裂5例、部分断裂6例。MRI对跟腱的形态及其内部结构显示直接、清晰、完整。跟腱损伤表现为跟腱不均匀增粗,腱内信号增高、紊乱,腱束的连续性完全中断或部分中断。结论:MRI能够直接显示外伤后跟腱的形态、内部结构及周围软组织改变,并能准确显示跟腱完全撕裂与部分撕裂的部位和程度,对临床诊治具有重要指导意义。     

MRI evaluation of acute renal trauma

We describe the MR findings in a patient with acute renal injury after blunt abdominal trauma associated with perinephric hematoma and urinoma. Both CT and MR findings are described. Active urine extravasation into a perinephric urinoma is demonstrated by serial post-contrast imaging with CT and MRI showing progressively increased attenuation/signal intensity fluid in communication with the collecting system, commencing 2 minutes after contrast administration.     

MRI of the rotator interval of the shoulder

The rotator interval of the shoulder joint is located between the distal edges of the supraspinatus and subscapularis tendons and contains the insertions of the coracohumeral and superior glenohumeral ligaments. These structures form a complex pulley system that stabilizes the long head of the biceps tendon as it enters the bicipital groove of the humeral head. The rotator interval is the site of a variety of pathological processes including biceps tendon lesions, adhesive capsulitis and anterosuperior internal impingement. This article describes the anatomy, function and pathology of the rotator interval using magnetic resonance imaging (MRI).