Patterns of ankle injury in soccer: MRI clues to traumatic mechanism.

Understanding the traumatic mechanisms of ankle injuries in soccer is crucial for an accurate and complete MRI diagnosis. Many ankle injuries share universal mechanisms seen in other athletic activities, but certain patterns are found to be more specific and relatively unique to soccer. Ankle impingement syndromes encountered in soccer encompass a spectrum of disorders that include anterior and posterior impingement categories, with anterior impingement representing pathology relatively specific to soccer. Lateral ligamentous sprains are one of the most common injuries; however, there is a higher rate of injuries to the medial structures in soccer as compared to other sports. Ankle fractures are uncommon in soccer while bone contusions and chondral and osteochondral injuries frequently accompany ligamentous sprains. Tendon abnormalities in soccer most commonly result from overuse injuries and typically affect peroneal tendons, posterior and anterior tibialis tendons, and Achilles tendon. Acute Achilles tendon ruptures occur in both recreational players and elite soccer athletes. Tibialis anterior friction syndrome may mimic tibial stress fractures. Long-term sequelae of acute traumatic and chronic overuse ankle injuries in professional soccer players manifest as ankle osteoarthritis that is more prevalent compared to not only the general population, but also to former elite athletes from other sports. This article examines the most common and specific injuries in soccer in order of their frequency.

Imaging and Treatment of Posttraumatic Ankle and Hindfoot Osteoarthritis.

Posttraumatic osteoarthritis of the ankle and hindfoot is a common and frequently debilitating disorder. 70% to 90% of ankle osteoarthritis is related to prior trauma that encompasses a spectrum of disorders including fractures and ligamentous injuries that either disrupt the articular surface or result in instability of the joint. In addition to clinical evaluation, imaging plays a substantial role in the treatment planning of posttraumatic ankle and hindfoot osteoarthritis. Imaging evaluation must be tailored to specific clinical scenarios and includes weight bearing radiography that utilizes standard and specialty views, computed tomography which can be performed with a standard or a weight bearing technique, magnetic resonance imaging, and ultrasound evaluation. This review article aims to familiarize the reader with treatment rationale, to provide a brief review of surgical techniques and to illustrate expected imaging appearances of common operative procedures performed in the setting of posttraumatic ankle and hindfoot osteoarthritis, such as joint-preserving procedures, ankle fusion, subtalar fusion, tibiotalarcalcaneal fusion and ankle arthroplasty. Preoperative findings will be discussed along with the expected postoperative appearance of various procedures in order to improve detection of their complications on imaging and to provide optimal patient care.

Egg-and-Banana Sign: A Novel Diagnostic CT Marker for Pulmonary Hypertension.

OBJECTIVE: The purpose of this study was to retrospectively determine whether the egg-and-banana sign, defined as the visualization of the main pulmonary artery (PA) at the level of the aortic arch, is a sensitive and specific diagnostic marker for pulmonary hypertension. MATERIALS AND METHODS: A total of 186 patients who, between January 2014 and July 2017, received right heart catheterizations and underwent CT studies that included the aortic arch within 140 days of catheterization were evaluated in this retrospective study. Of these patients, 127 had pulmonary hypertension (PH), and 59 who did not have PH served as control subjects. Two blinded radiologists reviewed each study for the egg-and-banana sign. The diameters of the main PA and ascending aorta were also measured. Contingency tables, ROC curves, and a t test were used for statistical analysis. RESULTS: The egg-and-banana sign was associated with a higher mean PA pressure, a higher ratio of the diameter of the PA to the diameter of the ascending aorta (Ao) (hereafter referred to as the "PA-to-Ao ratio"), and a larger PA diameter (p < 0.006). It had a specificity of 85% and a positive predictive value of 85%. When the egg-and-banana sign was used in combination with a main PA diameter larger than 29 mm and a PA-to-Ao ratio greater than 1, its specificity increased to 91% and 93%, respectively. When considered as individual markers, the PA diameter had a high sensitivity (80%; AUC value, 0.74) and the PA-to-Ao ratio had a high specificity (81%; AUC value, 0.73) for PH. Moderate correlations were noted between PA pressure and PA diameter (r = 0.37) and between PA pressure and PA-to-Ao ratio (r = 0.43). CONCLUSION: The egg-and-banana sign has a high specificity and PPV for PH. Specificity increased when the sign was used in combination with other classic CT markers.

ACR Appropriateness Criteria® Imaging After Total Knee Arthroplasty.

Total knee arthroplasty (TKA) is the most commonly performed joint replacement procedure in the United States and annual demand for primary TKA is expected to grow by 673% by 2030. The first part provides an overview of imaging modalities (radiographs, CT, MRI, ultrasound, and various nuclear medicine studies) and discusses their usefulness in the imaging evaluation of TKA. The second part focuses on evidence-based imaging and imaging-guided intervention algorithms for the workup of TKA and its complications, including routine follow-up, component wear, periprosthetic infection, aseptic loosening, granulomas/osteolysis, conventional and rotational instability, periprosthetic fracture, patellar complications, and a variety of periprosthetic soft tissue abnormalities. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.