Faculty Bibliography

BACKGROUND:The goal of the Latarjet procedure is restoration of shoulder stability enabled by accurate graft positioning and union. This study aimed to establish a reproducible method of quantitatively assessing coracoid graft osseous union percentage (OUP) using computed tomography (CT) scans and to determine the effect of other factors on the OUP. MATERIALS AND METHODS/METHODS:Postoperative CT scans of 41 consecutive patients treated with the open Latarjet procedure (37% primary, 63% revision) for anterior glenohumeral instability were analyzed for the OUP, position of the graft, and screw type and angle. Two musculoskeletal radiologists independently examined the images 2 times, and intraobserver and interobserver reliability was calculated using intraclass correlation coefficient (ICC). RESULTS:Mean OUP was 66% (range, 0%-94%) using quantitate methods, with good intraobserver reliability (ICC = 0.795) and interobserver reliability (ICC = 0.797). Nonunion and significant graft resorption was found in 2 patients. No significant difference was found in the mean OUP in the primary (63%) vs. revision Latarjet procedure (67%). Grafts were flush in 39%, medial in 36%, and lateral in 8%. The medial and neutral graft position was associated with slightly higher OUP (72% and 69%) compared with lateral (65%). OUP was higher when the superior screw angle was less than 17° and the inferior screw angle was less than 24°. This difference did not reach statistical significance. Screw type was not associated with significant difference in OUP. CONCLUSION/CONCLUSIONS:Quantitative assessment of osseous union of the graft using a reproducible method that we introduced showed similar OUP in the primary and revision Latarjet procedure.

OBJECTIVE:The aim of this article is to review the postoperative MRI appearances of irreparable massive rotator cuff tears (RCTs) after surgery was performed using newer techniques, including patch repair, muscle tendon transfer, superior capsular reconstruction, and subacromial balloon implantation. CONCLUSION/CONCLUSIONS:Newer surgical techniques are emerging for the management of massive RCTs. As radiologists become increasingly likely to encounter postoperative imaging studies of RCTs repaired using these techniques, familiarity with the normal postoperative appearances and complications associated with these techniques becomes important.

OBJECTIVE:The purpose of this study was to determine whether adding DWI to conventional MRI of the sacroiliac joints improves the diagnostic performance of MRI readers in the detection of sacroiliitis. MATERIALS AND METHODS/METHODS:values of patients with and those without sacroiliitis were compared. RESULTS:AUC was 0.758 (95% CI, 0.67-0.83). CONCLUSION/CONCLUSIONS:The addition of DWI to conventional MRI does not significantly improve overall diagnostic performance in terms of accuracy, sensitivity, or confidence in the detection of inflammatory sacroiliitis, but it does have increased specificity and interobserver agreement. ADC threshold values can be used as predictors of sacroiliitis but give no added advantage over MRI with DWI.

Purpose: As glenohumeral osteoarthritis progresses, there is increased risk for posterior glenoid bone loss which impacts an increasingly common treatment for these patients, total shoulder arthroplasty. Defining the level of maximum posterior bone loss and accurate assessment of its severity, using glenoid version measurements, are crucial to correctly align the glenoid prosthesis with glenoid to prevent prosthetic failure. While the importance of this information is clear, how these measurements should be performed remains in question with several techniques described in the literature. The purpose of this study was to define the most accurate level to measure glenoid version on CT for the most clinically relevant variants of posterior glenoid bone loss, Walch B2 and B3 types. Materials and Methods: 386 consecutive CT shoulder studies performed for shoulder arthroplasty preoperative planning between 2013- 2016 were retrospectively reviewed. Patients with B2 and B3 glenoid types were included. Two radiologists measured glenoid retroversion independently according to Friedman method on true axial CT images using the "intermediate glenoid line", at three glenoid heights: 25% (upper) 50% (equator) and 75% (lower). Results: 29 B2 and 8 B3 glenoid types were included. There was no statistically significant difference found in the retroversion measurements performed by each reader at the three glenoid levels on the B2 or B3 glenoid types (Mean angles (%) in upper, equator and lower in B2: 16.5, 17,0 and 17.5 and B3: 20.6, 20.7 and 23.2, respectively). There was substantial inter-reader correlation (r>=0.7) in angle measurements. Conclusion: Our study suggests that glenoid version can be accurately measured at any level between 25%-75%of the glenoid height forWalch B2 and B3 types. We recommend that the glenoid equator be used as the reference in order to assure consistent and reliable version measurements in this group of patients

We present two cases of pseudoaneurysm (PSA) about the shoulder mimicking more common clinical entities-soft tissue neoplasm and septic arthritis-for which biopsy of the mass and joint aspiration were requested respectively. We review the imaging findings of PSA with emphasis on findings in musculoskeletal protocol MRI, including the identification of pulsation artifact in both cases, which was critical to establishing the correct diagnosis. In the proper clinical setting, with imaging findings demonstrating a complex mass or fluid collection, MR images should be scrutinized for the presence of pulsation artifact, which can help diagnose a high-flow vascular lesion and avoid a potentially harmful invasive procedure such as biopsy.

Muscle herniations are rare and most reported cases involve muscles of the lower leg. We use a case of muscle herniation involving the semimembranosus muscle, presenting as a painful mass in an adolescent male after an unspecified American football injury, to highlight a simple concept of muscle biomechanics as it pertains to muscle hernia(s): decreased traction upon muscle fibers can increase conspicuity of muscle herniation(s)-this allows a better understanding of the apt provocative maneuvers to employ, during dynamic ultrasound or magnetic resonance imaging, in order to maximize diagnostic yield and, thereby, limit patient morbidity related to any muscle herniation. Our patient subsequently underwent successful decompressive fasciotomy and has since returned to his normal daily activities.

OBJECTIVE: Mueller-Weiss syndrome is a complex condition of the adult tarsal navicular characterized by progressive fragmentation leading to mid- and hindfoot pain and deformity. Since its first descriptions in the early 20th century, controversy has persisted regarding its pathogenesis. CONCLUSION: This article reviews the literature and discusses the anatomy, epidemiology, causes, clinical and radiologic findings, and treatment of Mueller-Weiss syndrome, and thus permits a better understanding of this disease and its management.

Vertebrobasilar dolichoectasia (VBD) is characterized by ectasia, elongation, and tortuosity of the vertebrobasilar arteries, with a high degree of variability in clinical presentation. The disease origin is believed to involve degeneration of the internal elastic lamina, thinning of the media secondary to reticular fiber deficiency, and smooth muscle atrophy. The prevalence of VBD is variable, ranging from 0.05% to 18%. Most patients with VBD are asymptomatic and their VBD is detected incidentally; however, it is important to recognize that the presence of symptoms, which can lead to clinically significant morbidity and sometimes mortality, may influence clinical management. The most important clinical presentations of VBD are vascular events, such as ischemic stroke and catastrophic intracranial hemorrhage, or progressive compressive symptoms related to compression of adjacent structures, including the cranial nerves, brainstem, or third ventricle, causing hydrocephalus. The imaging diagnostic criteria for computed tomography and magnetic resonance (MR) imaging include three quantitative measures of basilar artery morphology: laterality score, height of bifurcation, and basilar artery diameter. The authors review the relevant anatomy and disease origin of VBD; pertinent imaging findings, including intraluminal thrombus and relation to the cranial nerves; and imaging pitfalls, such as the hyperintense vessel sign on MR images and artifacts related to slow flow in the dolichoectatic vessel. In addition, clinical manifestations, the role of radiology in diagnosis and management of this condition, and available management options are reviewed. ((c))RSNA, 2016.

PURPOSE: This study aimed to determine the prevalence, importance, and types of incidental findings (IF) in non-enhanced CT scans performed for suspected renal colic, based on ACR white papers and other accepted radiographic recommendations. METHODS: Retrospective review of 5,383 consecutive finalized reports of nonenhanced CT using renal colic protocol performed on adult patients at 2 emergency departments over a 5.5-year period. IF were defined as those unrelated to symptoms (as opposed to alternate causes of symptoms) and were categorized as "important" if follow-up was recommended based on recently published consensus recommendations. Subsets of reports of those with important IF were blindly re-reviewed to calculate inter-rater variability for presence and categorization of important IF. RESULTS: Important IF were identified in 12.7% (95% confidence interval [CI]: 11.8%-13.6%) of scans. Prevalence of important IF increased with age: important IF in individuals age >80 years were 4 times more common than for those aged 18-30 years: 28.9% (95% CI: 22.4%-36.4%) versus 6.9% (95% CI: 5.5%-8.6%), respectively, P /= 0.69) regarding presence and classification of important IFs using published guidelines. CONCLUSIONS: Important IF occurred in 12.7% of non-enhanced CT scans performed for suspected renal colic in the emergency department and are more common in older individuals. Prospective studies that use radiographic recommendations to characterize IF and examine the outcome and cost of their workup are encouraged.