ABSTRACT Objective To correlate the significance of osseous, chondral, tendon, and ligamentous injuries with anatomical variations in low-grade versus high-grade acute ankle sprains. Methods We retrospectively identified the magnetic resonance imaging findings of acute ankle sprains (<15 days). Participants with a history of previous sprains, arthritis, tumors, infections, or inflammatory conditions were excluded. Images were independently evaluated by two musculoskeletal radiologists and assessed for osseous, chondral, tendon, and ligamentous injuries and anatomical variations. Participants were divided into low-grade versus high-grade sprain groups, according to the presence of a complete tear in at least one component of the lateral ligament complex. Results The final study group comprised 100 magnetic resonance images (mean age, 36 years), the majority of males (54%), the right ankle (52%), and a mean sprain duration of 5 days. Participants with high-grade sprains presented with increased rates of medial malleolus edema (p<0.001), moderate and large articular effusions (p=0.041), and shorter calcaneonavicular distance (p=0.008). Complete tears of the anterior talofibular ligament and calcaneofibular ligaments were observed in 100% and 51.2% of the participants in the High-Grade Group, respectively. The deltoid ligament complex was partially torn in this group (55.8% versus 8.8%, p<0.001). Extensor tendon retinaculum lesions occurred significantly more frequently in this group (41.9%) compared to the overall study population (23%) (p<0.001). Conclusion Participants with high-grade ankle sprains presented with shorter calcaneonavicular distances and increased rates of medial malleolus edema, deltoid complex partial tears, extensor retinaculum lesions, and articular effusion.

Resumo O achado de lesões ósseas focais não é incomum no dia-a-dia do radiologista. É, portanto, imprescindível saber discernir as lesões com potencial maligno agressivo, que requerem ação, das desprovidas de significado clínico, muitas destas sendo variantes da normalidade ou processos reativos benignos, às vezes, autolimitados. Em alguns casos, a confusão diagnóstica pode ter resultados catastróficos, como a realização de biópsia em casos de miosite ossificante, que pode levar ao diagnóstico incorreto de lesões de origem sarcomatosa e a cirurgias mutilantes. O presente estudo faz uma revisão dos principais aspectos radiológicos das lesões que mais comumente são vistas no dia-a-dia e que possuem potencial para causar confusão com processos ósseos malignos e agressivos. Ilustramos, ainda, essas lesões, apresentando casos do nosso serviço.

Abstract Focal bone lesions are not uncommon findings in the daily practice of radiology. Therefore, it is essential to differentiate between lesions with aggressive, malignant potential that require action and those that have no clinical significance, many of which are variants or benign lesions, sometimes self-limited and related to reactive processes. In some cases, a diagnostic error can have catastrophic results. For example, a biopsy performed in a patient with myositis ossificans can lead to an incorrect diagnosis of sarcomatous lesions and consequently to mutilating surgical procedures. The present study reviews the main radiological aspects of the lesions that are most commonly seen in daily practice and have the potential to be confused with aggressive, malignant bone processes. We also illustrate these entities by presenting cases seen at our institution.

RESUMO Objetivo: Avaliar o desempenho da ultrassonografia na avaliação dos ligamentos do cotovelo, comparando os achados com ressonância magnética. Métodos: Estudo prospectivo unicêntrico envolvendo 30 pacientes, sem alterações articulares nos cotovelos. Dois ultrassonografistas experientes avaliaram ambos os cotovelos de cada um dos pacientes, com 60 avaliações cada médico e 120 avaliações no total. As imagens de ressonância magnética foram obtidas em aparelhos 3 Tesla. Dois radiologistas experientes avaliaram as imagens, com total de 120 exames. Cada examinador deu uma nota subjetiva, de zero a 5, para os ligamentos avaliados; zero correspondeu a ligamento não identificado, e 5 a ligamento visualizado integralmente. Foi considerado nível de significância de 5%. Para cada par de medidas obtidas, construíram-se dispersões e parcelas de Bland-Altman. Resultados: Todos os ligamentos foram identificados pelos examinadores de ultrassonografia, recebendo pontuação 4 ou 5, em relação à sua visibilidade, e foram identificados pelos examinadores de ressonância magnética, com pontuação 5. Foram considerados intactos e saudáveis pelos quatro examinadores. As comparações entre ultrassonografia e ressonância magnética na avaliação dos ligamentos do cotovelo não demostraram diferenças significativas. Conclusão: Quando realizada por examinadores experientes, a ultrassonografia pode ser considerada semelhante à ressonância magnética na avaliação de ligamentos do cotovelo.

ABSTRACT Objective: To determine the value of ultrasonography in elbow ligament assessment compared to magnetic resonance imaging. Methods: A prospective single-center study involving 30 volunteers with no elbow joint changes. Two experienced ultrasound specialists evaluated both elbows of each volunteer, resulting in 60 evaluations per physician and totaling up 120 evaluations. Magnetic resonance images were obtained using a 3-Tesla machine and evaluated by two experienced radiologists, totaling up 120 exams. Each examiner assigned subjective, zero-to-5 scores to ligaments imaged, where zero corresponded to non-identified ligament and 5 to visualization of the entire ligament. The level of significance was set at 5%. Bland-Altman dispersions and plots were prepared for each pair of measurements obtained. Results: All ligaments were amenable to sonographic identification; scores of 4 or 5 were assigned by examiners based on ligament visibility. Ligaments could also be identified using magnetic resonance imaging and were assigned scores of 5 by examiners. All ligaments were described as intact and healthy by all four examiners. Comparative analysis of elbow ligament sonographic and magnetic resonance imaging findings did not differ significantly. Conclusion: Ultrasonography and magnetic resonance imaging can be considered equivalent modalities for elbow ligament assessment in the hands of experienced examiners.

OBJETIVO: Demonstrar os achados em ressonância magnética (RM) da tromboflebite plantar. MÉTODOS: Revisão retrospectiva de 20 pacientes com dor na região plantar nos quais os achados de ressonância magnética indicaram tromboflebite plantar. RESULTADOS: Foram avaliados 14 homens e seis mulheres, com idade média de 46,7 anos. Oito desses pacientes também foram submetidos à ultrassonografia com doppler, que confirmaram a tromboflebite. As imagens de ressonância magnética foram avaliadas em consenso por dois radiologistas com experiência em radiologia do sistema musculoesquelético (mais de 10 anos cada um), demonstrando edema perivascular em todos os 20 pacientes (100%) e edema muscular em 19 dos 20 pacientes (95%). Todos os 20 pacientes apresentavam intensidade de sinal intermediária intraluminal em T2 (100%) e ectasia venosa estava presente em 17 dos 20 casos (85%). Veias colaterais foram visualizadas em um dos 20 pacientes (5%). Todos os 14 casos (100%), nos quais o contraste intravenoso foi administrado, apresentavam realce dos tecidos perivenulares e defeito de enchimento intraluminal. Ectasia venosa, perda da compressibilidade e ausência de fluxo na ultrassonografia com doppler também foram observados em todos os oito casos examinados pelo método. CONCLUSÕES: A RM é um método sensível na avaliação de tromboflebite plantar em pacientes com dor plantar.

OBJECTIVE: demonstrate the magnetic resonance imaging (MRI) findings in plantar thrombophlebitis. METHODS: Retrospective review of twenty patients with pain in the plantar region of the foot, in which the MRI findings indicated plantar thrombophlebitis. RESULTS: A total of fourteen men and six women, mean age 46.7 years were evaluated. Eight of these patients also underwent Doppler ultrasonography, which confirmed the thrombophlebitis. The magnetic resonance images were evaluated in consensus by two radiologists with experience in musculoskeletal radiology (more than 10 years each), showing perivascular edema in all twenty patients (100%) and muscle edema in nineteen of the twenty patients (95%). All twenty patients had intraluminal intermediate signal intensity on T2-weighted (100%) and venous ectasia was present in seventeen of the twenty cases (85%). Collateral veins were visualized in one of the twenty patients (5%). All fourteen cases (100%), in which intravenous contrast was administered, showed perivenular tissues enhancement and intraluminal filling defect. Venous ectasia, loss of compressibility and no flow on Doppler ultrasound were also observed in all eight cases examined by the method.