Whole-body muscle magnetic resonance imaging in inflammatory myopathy with mitochondrial pathology.

Introduction: Inflammatory myopathy with mitochondrial pathology (IM-Mito) is a rare condition described in a few case series, and it is not clear whether it is a specific disease or a variant of Inclusion Body Myositis (IBM). Radiological data of IM-Mito patients has only been evaluated in one study. Aim: To analyze whole-body muscle magnetic resonance imaging (MRI) features in patients with IM-Mito compared with individuals with IBM. Methods: Fourteen IM-Mito and ten IBM patients were included. IM-Mito was defined by endomysial inflammatory infiltrate, presence of at least 1% of Cytochrome C Oxidase negative fibers, and absence of rimmed vacuoles in muscle biopsy; and IBM was defined by the presence of dystrophic muscular abnormalities, endomysial inflammatory infiltrate, and rimmed vacuoles. Patients underwent clinical evaluation and whole-body muscle MRI to determine the presence of edema, and fatty infiltration in various muscles. Results: Muscle imaging abnormalities were asymmetric in most patients with IM-Mito and IBM. Muscles with the highest average degree of fatty infiltration in both conditions were the quadriceps and medial gastrocnemius. Most patients with IM-Mito and IBM showed imaging patterns of rectus femoris relatively spared compared to other quadriceps muscles. The flexor digitorum profundus was the most affected muscle of the upper limbs in both IBM and IM-Mito. Discussion: Although the results suggest some similarities in muscle imaging features between IM-Mito and IBM, there remains uncertainty whether these two conditions are part of the same clinical spectrum.

Imaging spectrum of atraumatic muscle disorders: a radiologist's guide.

Atraumatic muscle disorders comprise a very wide range of skeletal muscle diseases, including metabolic, inflammatory, autoimmune, infectious, ischemic, and neoplastic involvement of the muscles. Therefore, one must take clinical and laboratory data into consideration to elucidate the differential diagnoses, as well as the distribution of the muscle compromise along the body-whether isolated or distributed along the body in a symmetric or asymmetrical fashion. Assessment of muscular disorders often requires imaging investigation before image-guided biopsy or more invasive procedures; therefore, radiologists should understand the advantages and limitations of imaging methods for proper lesion evaluation and be aware of the imaging features of such disorders, thus contributing to proper decision-making and good patient outcomes. In this review, we propose a systematic approach for the assessment of muscle disorders based on their main imaging presentation, dividing them into patterns that can be easily recognized.

Clinical and Radiological Results after Endoscopic Treatment for Gluteal Tendon Injuries with a Minimum Follow-Up of 12 Months.

Objectives: The study aimed to evaluate the clinical and radiological results after endoscopic repair of gluteus medius muscle injuries and proposed an anatomical classification for the different injury classes. Methods: A retrospective case series, including patients who had undergone endoscopic repair of the hip abductor tendon. The surgical procedure was standardized. Magnetic resonance imaging (MRI) studies were analyzed, and the injuries were classified into three types: nontransfixing partial-extension (nTPE) tear, transfixing partial-extension (TPE) tear, and transfixing full-extension (TFE) tear. TPE and TFE were considered high-grade tears. The postoperative outcomes were as follows: duration of walking aid requirement, duration of physical therapy, time to return to daily activities, modified Harris Hip score (mHHS) and Nonarthritic Hip Score (NAHS) functional scores, pain visual analog scale (VAS), satisfaction, claudication, Trendelenburg test, and reoperation. Results: Sixteen patients were included (94% women; mean age 65 years), with a mean follow-up of 42 months (12-131, range). Out of the cases with preoperative exams available for analysis, four cases (31%) were nTPE, three (23%) TPE, and six (46%) TFE tears. Thus, 69% of the patients had high-grade injuries. These patients had a higher degree of fat infiltration (P = 0.034), but this was not correlated with inferior postoperative clinical or radiological results. One patient required reoperation due to a recurrent injury. Conclusion: Isolated extra-articular injuries to the tendons of the gluteus medius and minimus evolved satisfactorily after endoscopic repair. Due to the small number of cases, it was not possible to observe differences in outcomes between high-and low-grade injuries.

MRI of Pediatric Foot and Ankle Conditions.

The increase in competitive sports practice among children and lack of ionizing radiation have resulted in a higher demand for MRI examinations. MRI of the children skeleton has some particularities that can lead orthopedists, pediatricians, and radiologists to diagnostic errors. The foot and ankle have several bones with abundant radiolucent and high signal intensity cartilage in several ossification centers, apophysis and physis, that can make this interpretation even harder. The present revision aims to show, how to differentiate between normal developmental findings and anatomic variants from pathologic conditions, whether mechanical, inflammatory, infectious, or neoplastic.

Whole-Body MRI in Musculoskeletal Oncology: A Comprehensive Review with Recommendations.

Whole-body (WB) MRI has emerged as an attractive method for oncologic evaluation, potentially replacing conventional imaging modalities and providing a one-step wide-coverage assessment of both the skeleton and soft tissues. In addition to providing anatomic information, WB MRI may also yield a functional analysis with the inclusion of diffusion-weighted imaging (DWI). DWI translates microstructural changes, resulting in an excellent alternative to fluorodeoxyglucose PET/CT. WB MRI (with DWI) offers comparable accuracy to PET/CT and has the advantage of avoiding ionizing radiation. Technological advances and the development of faster protocols have prompted greater accessibility of WB MRI, with growing applications in routine practice for the diagnosis, staging, and follow-up of cancer. This review discusses the technical considerations, clinical applications, and accuracy of WB MRI in musculoskeletal oncology. Keywords: Pediatrics, MR Imaging, Skeletal-Axial, Skeletal-Appendicular, Soft Tissues/Skin, Bone Marrow, Extremities, Oncology, Musculoskeletal Imaging © RSNA, 2023.

Prevalence of phalangeal bone marrow edema on MRI before and during the COVID-19 pandemic and correlation with chilblain skin lesions.

OBJECTIVE: The purpose of this study is to establish the prevalence bone marrow edema of the phalanges of the feet and hands before and during the COVID-19 pandemic on MRI studies and correlate with clinically chilblain skin lesions and epidemiological data. METHODS: This observational retrospective study. In patients with confirmed bone marrow edema of the phalanges, epidemiological data and clinical findings were collected, including the history of current or remote COVID-19 infection and vaccination status. The two-proportion test was used to compare the frequency of bone marrow edema in the phalanges before and during the pandemic, and the comparison between the categories variables was performed using the one-proportion test. RESULTS: Of the total of 7215 patients, only 20 presented isolated bone marrow edema of the digits in MRI studies; 2 (0.05%) were found two years before the pandemic's beginning, and 18 (0.64%) after the pandemic's onset, demonstrating an increase of 13-fold in this period. 16 were women with a mean age of 40.3 years and 4 were men with a mean age of 53.5 years. The most frequently reported clinical symptoms by the patients were pain (85.0%), and erythema of the skin (45.0%). Of the 18 patients found after the pandemic's onset, only 27.8% had COVID-19 infections confirmed by RT-PCR before the imaging study, and all cases were mild. CONCLUSION: This study demonstrated a significant increase in the prevalence of bone marrow edema of the phalanges after the onset of the COVID-19 pandemic, particularly in middle-aged and younger women.

Image-Guided Percutaneous Needle Biopsy for Benign and Malignant Bone Tumors: Systematic Review and Meta-Analysis.

PURPOSE: To compare the diagnostic yield and accuracy of both image-guided core-needle biopsy (CNB) and fine-needle biopsy and evaluate the benefit of performing fine-needle biopsy in addition to CNB in patients with suspected benign and malignant bone tumors. MATERIALS AND METHODS: A systematic search was performed on March 10, 2021, to determine whether fine-needle aspiration (FNA) plays any role when performed alone or in combination with CNB. The included studies were aggregated for the pooled estimates of diagnostic yield and histologic accuracy of image-guided percutaneous needle biopsy of bone tumors. Twenty-nine studies published between 1996 and 2021 were included. RESULTS: When all patients with bone tumors were included, the rates of diagnostic yield and accuracy of FNA and CNB were 88.5% and 82.5% and 91.4% and 92.7%, respectively; the rates of both the methods combined were 96.5% and 94.1%, respectively; and for the lytic subgroup, the rates of diagnostic yield and accuracy of CNB and both the methods combined were 94.3% and 100% and 98.9% and 90.4%, respectively. A P value of <.05 was considered statistically significant. CONCLUSION: The present meta-analysis showed that core biopsy alone outperformed fine-needle biopsy alone in all categories of benign and malignant tumors. Additionally, the diagnostic yield was improved when FNA was used in addition to CNB for lytic bone lesions.

Could ultrasound and muscle elastography be associated with clinical assessment, laboratory and nailfold capillaroscopy in juvenile dermatomyositis patients?

Abstract Background Juvenile Dermatomyositis (JDM) is the most common idiopathic inflammatory myopathy in children. Imaging exams are useful for muscle assessment, with ultrasonography (US) being a promising tool in detecting disease activity and tissue damage. There are few studies about muscle elastography. Objectives Our aim was to associate clinical, laboratory, and nailfold capillaroscopy (NC) assessments with US in JDM patients; and to compare the findings of US and Strain Elastography (SE) from patients and healthy controls. Methods An analytic cross-sectional study was performed with JDM patients and healthy controls. Patients underwent clinical exam to access muscle strength and completed questionnaires about global assessment of the disease and functional capacity. Patients were submitted to NC and measurement of muscle enzymes. All subjects underwent US assessment, using gray scale, Power Doppler (PD), and SE. Results Twenty-two JDM patients and fourteen controls, aged between 5 and 21 years, matched for age and sex were assessed. In qualitative and semi-quantitative gray scale, we observed a higher frequency of alterations in patients (p < 0.001), while in PD, there was a higher frequency of positivity in patients' deltoids and anterior tibialis (p < 0.001). Active disease was associated with an important change in the semi-quantitative gray scale in deltoids (p = 0.007), biceps brachii (p = 0.001) and quadriceps femoris (p = 0.005). The SE demonstrated a high negative predictive value of 87.2. Conclusion US was able, through gray scale, to differentiate JDM patients from controls, while PD achieved such differentiation only for deltoids and anterior tibialis. The semi-quantitative gray scale showed disease activity in proximal muscles. SE was not able to differentiate patients from controls.

Chronic nonbacterial osteomyelitis: the role of whole-body MRI.

BACKGROUND: Chronic nonbacterial osteomyelitis (CNO), also known as chronic recurrent multifocal osteomyelitis, is a noninfectious autoinflammatory disorder that occurs primarily in children and adolescents and is characterized by episodic musculoskeletal pain with a protracted course. MAIN BODY: Traditionally, the diagnosis of CNO is made by exclusion and commonly requires bone biopsy to rule out infection and malignancy. However, bone biopsy may be avoided when imaging and clinical characteristic features are present, such as multifocal bone lesions at typical sites, no constitutional symptoms and no signs of infection in laboratory test results. Whole-body magnetic resonance imaging (WB-MRI) can assess signs of acute and chronic inflammation and enables the detection of CNO typical patterns of lesion location and distribution, thereby helping to exclude differential diagnosis. The goal of the present study paper is to review the main clinical and imaging aspects of the disease with emphasis on the role of WB-MRI in the diagnosis, assessment of disease burden and follow-up monitoring. CONCLUSION: Radiologists need to be familiar with the imaging features to suggest the diagnosis as the early therapy may help to avoid irreversible secondary damage of skeletal system.

Sacroiliac joint beyond sacroiliitis-further insights and old concepts on magnetic resonance imaging.

The sacroiliac joint (SIJ) is an amphiarthrosis composed of a posterior syndesmosis and an anterior cartilaginous portion, with limited yet present mobility. Its main function is to transmit the load from the axial skeleton to the lower limbs and vice-versa; it is susceptible to early mechanical and degenerative changes which are much more common than inflammatory sacroiliitis. Magnetic resonance imaging (MRI) has increasingly been used to evaluate these changes, and while subchondral bone marrow edema (BME) is a common finding related to both, care must be taken when applying the ASAS research MRI definition for sacroiliitis without considering lesion BME topography, size and depth, concomitant structural damage and, of course, the clinical picture. In this review, we will discuss the anatomy and biomechanics of the SIJ, the noninflammatory causes of SIJ subchondral BME, and how these concepts combined can be used to increase our diagnostic confidence.

O papel da estereorradiografia na avaliação das deformidades dos membros inferiores / The role of stereoradiography in the evaluation of lower limb deformities

Resumo As deformidades dos membros inferiores são uma condição comum e podem levar a alterações da marcha e afetar a função e longevidade das articulações do quadril, do joelho e da coluna. Uma abordagem diagnóstica sistemática é essencial para definir o tratamento e alcançar o resultado terapêutico desejado com a menor taxa de complicações. A radiografia panorâmica é frequentemente utilizada para caracterizar as deformidades dos membros inferiores por meio de medidas de comprimento e desvios angulares dos eixos, além de se tratar de um método de baixo custo e alta disponibilidade. No entanto, como é frequente a combinação de deformidades em dois ou três planos ortogonais dos membros, a avaliação radiográfica perde acurácia por se tratar de um método de imagem bidimensional. Nesse sentido, deformidades em valgo/varo avaliadas radiograficamente no plano coronal apresentarão variações crescentes nas medidas dependendo do grau de flexão/recurvatum, torções ósseas anômalas ou, não menos importante, um posicionamento inadequado. A estereorradiografia biplanar de baixa dose, por meio de modelos tridimensionais, permite obter medidas mais acuradas de vários parâmetros usados na avaliação das deformidades dos membros inferiores, incluindo comprimentos, eixos e as torções tibial e femoral, antes disponíveis apenas pela tomografia computadorizada, com a vantagem de ser realizada em posição funcional com carga. Além disso, por permitir uma avaliação global da cabeça aos pés, abre uma nova perspectiva de compreender a inter-relação das deformidades dos membros com o posicionamento da bacia e com as deformidades da coluna.

Abstract Deformities of the lower limbs are a common condition and can lead to changes in gait, as well as affecting the function and longevity of the hips, knees, and spine. A systematic approach is essential to achieve the desired therapeutic result with the lowest rate of complications. Panoramic radiography is a widely available, low-cost method that is commonly used in order to assess the length and angular deformities of the lower limbs, by measuring the length and angular deviations of the axes. However, because the combination of lower limb deformities in two or three orthogonal planes is common, conventional radiography lacks accuracy because it is a two-dimensional imaging method. Therefore, the measurements of valgus/varus deformities on X-rays restricted to the coronal plane will present increasing variations in measurements depending on the degree of flexion/recurvatum alignment, anomalous bone torsions, or, last but not least, inappropriate patient positioning. Low-dose biplanar stereoradiography using three-dimensional models increases the accuracy of the measurement of several parameters used in the evaluation of lower limb alignment, including lengths, axes, and tibial/femoral torsions, parameters that could previously be evaluated only by computed tomography. Stereoradiography also makes it possible to perform a head-to-toe evaluation, as well as to evaluate the interactions among the lower limbs, pelvis, and spine.

Knee MR Using a Body Coil is Equivalent to CT in Measuring the TT-TG Distance: Removing the Systematic Bias.

Objective To compare magnetic resonance imaging (MRI) using a body coil with computed tomography (CT) in measuring the tibial tubercle-trochlear groove distance (TT-TG) and the patellar tendon-cartilaginous trochlear groove (PT-CTG) distances, and evaluate interrater reliability. Methods The study group consisted of 34 knees from 17 asymptomatic subjects with no history of knee pathology, trauma or surgery. A low-dose CT scan and an axial T1-weighted MRI sequence of the knees were performed with rigorous standardization of the positioning with full extension of the knees and parallel feet. Two musculoskeletal radiologists performed the measurements independently. The reliability of the TT-TG and PT-CTG distances on CT (17.1 ± 4.2 mm and 17.3 ± 4.2 mm) and of MRI (16.2 ± 3.7 mm and 16.5 ± 4.1 mm) was assessed by intraclass correlation coefficient (ICC [2,1]) and Bland-Altman graphs, as well as the interrater reliability for both methods. Results Good reliability and agreement was observed between CT and MRI measurements for TT-TG and PT-CTG, with an ICC of 0.774 ( p < 0.001) and 0.743 ( p < 0.001), respectively, and no systematic bias was observed. The interrater reliability was excellent for all measurements on both imaging methods. Conclusion This was the first study that compared MRI using a body coil with CT in measuring the TT-TG distance, with the potential clinical implication that the CT in this clinical setting could be avoided.

Knee MR Using a Body Coil is Equivalent to CT in Measuring the TT-TG Distance: Removing the Systematic Bias / A ressonância magnética do joelho usando a bobina de corpo é equivalente à TC na medição da distância TT-ST: Removendo o viés sistemático

Abstract Objective To compare magnetic resonance imaging (MRI) using a body coil with computed tomography (CT) in measuring the tibial tubercle-trochlear groove distance (TT-TG) and the patellar tendon-cartilaginous trochlear groove (PT-CTG) distances, and evaluate interrater reliability. Methods The study group consisted of 34 knees from 17 asymptomatic subjects with no history of knee pathology, trauma or surgery. A low-dose CT scan and an axial T1-weighted MRI sequence of the knees were performed with rigorous standardization of the positioning with full extension of the knees and parallel feet. Two musculoskeletal radiologists performed the measurements independently. The reliability of the TT-TG and PT-CTG distances on CT (17.1 ± 4.2 mm and 17.3 ± 4.2 mm) and of MRI (16.2 ± 3.7 mm and 16.5 ± 4.1 mm) was assessed by intraclass correlation coefficient (ICC [2,1]) and Bland-Altman graphs, as well as the interrater reliability for both methods. Results Good reliability and agreement was observed between CT and MRI measurements for TT-TG and PT-CTG, with an ICC of 0.774 (p< 0.001) and 0.743 (p< 0.001), respectively, and no systematic bias was observed. The interrater reliability was excellent for all measurements on both imaging methods. Conclusion This was the first study that compared MRI using a body coil with CT in measuring the TT-TG distance, with the potential clinical implication that the CT in this clinical setting could be avoided.

Resumo Objetivo Comparar a ressonância magnética (RM) usando uma bobina corporal e tomografia computadorizada (TC) na medição da distância tubérculo tibial-sulco troclear (TT-ST) e as distâncias tendão patelar-sulco troclear cartilaginoso (TP-STC), e avaliar a confiabilidade interavaliador. Métodos O grupo de estudo consistiu em 34 joelhos de 17 indivíduos assintomáticos sem história de patologia, trauma ou cirurgia no joelho. Uma tomografia computadorizada (TC) de baixa dose e uma sequência axial de RM ponderada em T1 dos joelhos foram realizadas com padronização rigorosa do posicionamento com extensão total dos joelhos e pés paralelos. Dois radiologistas musculoesqueléticos realizaram as medidas de forma independente. A confiabilidade das distâncias TT-ST e TP-STC na TC (17,1 ± 4,2 mm e 17,3 ± 4,2 mm) e RM (16,2 ± 3,7 mm e 16,5 ± 4,1 mm), foi avaliada pelo coeficiente de correlação intraclasse (CCI [2,1)]) e gráficos Bland-Altman, bem como a confiabilidade entre avaliadores para ambos os métodos. Resultados Boa confiabilidade e concordância foram observadas entre as medidas de TC e RM para TT-ST e TP-STC com um CCI de 0,774 (p< 0,001) e 0,743 (p< 0,001), respectivamente, e nenhum viés sistemático foi observado. A confiabilidade entre avaliadores foi excelente para todas as medições em ambos os métodos de imagem. Conclusão Este foi o primeiro estudo que comparou a RM usando bobina de corpo com a TC na medição da distância TT-ST, com a implicação clínica potencial de que a TC neste cenário clínico poderia ser evitada.

O papel da ressonância magnética na avaliação da gluteoplastia: aspectos habituais e complicações / The role of magnetic resonance in the evaluation of gluteoplasty: habitual aspects and complications

RESUMO Introdução: Os procedimentos estéticos na região glútea têm ganhado evidência nas últimas décadas, com aumento da procura e aparecimento de novas técnicas. Somado ao desenvolvimento e maior facilidade de acesso aos métodos de imagem, assim como a crescente judicialização da medicina, tornam-se cada vez mais frequentes os exames de imagem nos pacientes submetidos a gluteoplastia, com destaque atualmente para a avaliação por ressonância magnética desta região. Dessa forma, a imagem entra cada vez mais na prática clínica diária do cirurgião plástico, requerendo do mesmo conhecimentos sobre conceitos básicos em relação à solicitação e interpretação dos exames. Neste artigo, revisamos aspectos de imagem por ressonância magnética de procedimentos estéticos da região glútea, bem como suas complicações. O objetivo é ilustrar através de estudos de ressonância magnética os achados habituais nos procedimentos de gluteoplastia, bem como algumas de suas complicações, além de propor um protocolo de exame por ressonância magnética da região. Foram selecionados selecionados casos ilustrativos de pacientes que se submeteram a procedimentos de gluteoplastia, sejam eles aprovados, off-label ou mesmo ilícitos, e que fizeram estudo de ressonância magnética em nosso serviço. Foi realizada ainda revisão bibliográfica sobre o tema.

ABSTRACT Introduction: Aesthetic procedures in the gluteal region are increasingly in evidence in recent decades with the augment in demand and the emergence of new techniques. This fact, coupled with the development and easier access to imaging methods and the increasing judicialization of medicine, makes imaging exams more frequent in patients undergoing gluteoplasty, with an emphasis currently on magnetic resonance imaging in this region. Thus, the image increasingly enters the plastic surgeon's daily clinical practice, requiring knowledge of basic concepts regarding the request and interpretation of the exams. In this article, we reviewed aspects of magnetic resonance imaging of aesthetic procedures in the gluteal region and their complications. The objective is to, through magnetic resonance studies, the usual findings in gluteoplasty procedures, as well as some of their complications, in addition to proposing an examination protocol for magnetic resonance imaging in the region. Illustrative cases of patients who underwent gluteoplasty procedures, whether approved, off-label or even illicit, were selected, in which we conducted a magnetic resonance study in our service. A bibliographic review was also done on the topic.

Osteochondral lesions of the talar dome: an up-to-date approach to multimodality imaging and surgical techniques.

Osteochondral lesions (OCLs) of the talar dome consist of a multifactorial pathology of the articular cartilage and subchondral bone and can result in persistent ankle pain and osteoarthritis (OA). Along with a physical examination and clinical history, an imaging evaluation plays a pivotal role in the diagnosis of these lesions and is fundamental for making treatment decisions and determining prognosis by providing information regarding the size, location, and cartilage and subchondral bone statuses as well as associated lesions and degenerative changes. Multiple surgical techniques for OCLs of the talar dome have been developed in recent decades, including cartilage repair, regeneration, and replacement strategies, and radiologists should be acquainted with their specific expected and abnormal postoperative imaging findings to better monitor the results and predict poor outcomes. The present article proposes a thorough review of the ankle joint anatomy and biomechanics, physiopathology, diagnosis, and treatment of OCLs of the talar dome, highlighting the radiological approach and imaging findings in both pre- and postoperative scenarios.

The Role of Whole-Body MRI in Pediatric Musculoskeletal Oncology: Current Concepts and Clinical Applications.

Whole-body magnetic resonance imaging (WB-MRI) has gained importance in the field of musculoskeletal oncology over the last decades, consisting in a one-stop imaging method that allows a wide coverage assessment of both bone and soft tissue involvement. WB-MRI is valuable for diagnosis, staging, and follow-up in many oncologic diseases and is especially advantageous for the pediatric population since it avoids redundant examinations and exposure to ionizing radiation in patients who often undergo long-term surveillance. Its clinical application has been studied in many pediatric neoplasms, such as cancer predisposition syndromes, Langerhans cell histiocytosis, lymphoma, sarcomas, and neuroblastoma. The addition of diffusion-weighted sequences allows functional evaluation of neoplastic lesions, which is helpful in the assessment of viable tumor and response to treatment after neoadjuvant or adjuvant therapy. WB-MRI is an excellent alternative to fluorodeoxyglucose-positron emission tomography/computed tomography in oncologic children, with comparable accuracy and the convenience of being radiation-free, fast to perform, and available at a similar cost. The development of new techniques and protocols makes WB-MRI increasingly faster, safer, and more accessible, and it is important for referring physicians and radiologists to recognize the role of this imaging method in pediatric oncology. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.

The Role of Magnetic Resonance in the Diagnosis of Chronic Exertional Compartment Syndrome / O papel da ressonância magnética no diagnóstico da síndrome compartimental crônica do exercício

Abstract Chronic compartment syndrome is a common and often underdiagnosed exercise-induced condition, accounting on average for a quarter of cases of chronic exertional pain in the leg, second only to the fracture/tibial stress syndrome spectrum. It traditionally occurs in young runner athletes, although more recent studies have demonstrated a considerable prevalence in low-performance practitioners of physical activity, even in middle-aged or elderly patients. The list of differential diagnoses is extensive, and sometimes it is difficult to distinguish them only by the clinical data, and subsidiary examinations are required. The diagnosis is classically made by the clinical picture, by exclusion of the differential diagnoses, and through the measurement of the intracompartmental pressure. Although needle manometry is considered the gold standard in the diagnosis, its use is not universally accepted, since there are some important limitations, apart from the restricted availability of the needle equipment in Brazil. New protocols of manometry have recently been proposed to overcome the deficiency of the traditional ones, and some of them recommend the systematic use of magnetic resonance imaging (MRI) in the exclusion of differential diagnoses. The use of post-effort liquid-sensitive MRI sequences is a good noninvasive option instead of needle manometry in the diagnosis of chronic compartment syndrome, since the increase in post-exercise signal intensity is statistically significant when compared with manometry pressure values in asymptomatic patients and in those with the syndrome; hence, the test can be used in the diagnostic criteria. The definitive treatment is fasciotomy, although there are less effective alternatives.

Resumo A síndrome compartimental crônica é uma condição comum e frequentemente subdiagnosticada, induzida pelo exercício, que corresponde em média a um quarto dos casos de dor crônica na perna relacionada ao exercício, e que perde em frequência apenas para o espectro fratura/reação ao estresse tibial. Tradicionalmente ocorre em jovens atletas corredores, embora estudos mais recentes tenham demonstrado uma prevalência considerável em praticantes de atividade física de baixo rendimento, mesmo em pacientes de meia-idade ou idosos. A lista de diagnósticos diferenciais é extensa, e por vezes é difícil fazer a distinção apenas pelos dados clínicos, sendo necessários exames subsidiários. Classicamente, o diagnóstico é feito pelo quadro clínico, pela exclusão dos diferenciais, e pela medida pressórica intracompartimental. Embora a manometria por agulha seja considerada o padrão-ouro no diagnóstico, seu uso não é universalmente aceito, visto que existem algumas limitações importantes, além da disponibilidade restrita do equipamento com agulha no Brasil. Recentemente, novos protocolos de manometria têm sido propostos a fim suplantar a deficiência dos tradicionais, com algum deles inclusive recomendando o uso sistemático da ressonância magnética (RM) na exclusão dos diagnósticos diferenciais. O uso de sequências de RM sensíveis a líquido pós-esforço é uma ótima opção não invasiva à manometria por agulha no diagnóstico da síndrome compartimental crônica, uma vez que o aumento da intensidade de sinal pós-exercício é estatisticamente relevante quando comparados os valores pressóricos de manometria em pacientes com a síndrome e assintomáticos; portanto, o exame pode ser usado no critério diagnóstico. O tratamento definitivo é a fasciotomia, embora existam alternativas menos eficazes.

Clinical and imaging hallmarks of the MYH7-related myopathy with severe axial involvement.

INTRODUCTION: MYH7 gene mutations are related to a heterogeneous group of skeletal and cardiac myopathies. METHODS: We evaluated clinical and muscle MRI changes in patients with mutations in the rod domain of MYH7, including 1 with mosaicism and 3 with novel missense mutations. RESULTS: Patients presented in childhood with a distal and axial phenotype. Biopsy findings were variable. Half of the cases displaying some type of core pathology, including minicores and eccentric cores. Most patients demonstrated internal bands of infiltration ("inverted-collagen-VI sign") in multiple muscles, particularly the soleus, and prominent atrophy and fatty infiltration of the tongue and the paraspinal, gluteus minimus, sartorius, gracilis, tibialis anterior, and extensor digitorum longus muscles. DISCUSSION: Muscle imaging findings in patients with axial involvement provide significant clues permitting the distinction between MYH7-related myopathies and other axial myopathies such as those related to SEPN1 and LMNA genes. Muscle Nerve 58: 224-234, 2018.

Natural evolution of popliteomeniscal fascicle tears over 2 years and its association with lateral articular knee cartilage degeneration in patients with traumatic anterior cruciate ligament tear.

OBJECTIVES: To assess (i) normal imaging anatomy of the popliteomeniscal fascicles, (ii) prevalence and natural evolution of popliteomeniscal fascicle tears (PMFT) in subjects with traumatic anterior cruciate ligament (ACL) tears over 2 years and (iii) compare knee cartilage degeneration in subjects with and without PMFT longitudinally. METHODS: 57 subjects with ACL tears were screened for PMFT. Morphological (high-resolution 3D fast spin-echo) and compositional (T1ρ and T2 mapping) MR imaging was performed prior to and 2 years after ACL reconstruction. Differences of morphological and compositional parameters were compared between subjects with and without PMFT using logistic regression, adjusting for age, sex and BMI. RESULTS: In 24% (n = 14) of the subjects with ACL tear a PMFT was detected on baseline MRI. One subject with PMFT developed a meniscal tear over 2 years. Cartilage ∆T1ρ of the lateral femur increased significantly more in subjects with isolated PMFT compared to controls (mean difference, 2.0 ± 2.9 vs. -1.3 ± 1.6, p = 0.027). CONCLUSION: PMFT detected by MRI are a common finding in subjects with ACL tears. Subjects with these defects showed higher compositional cartilage deterioration compared to controls, over 2 years in the lateral femoral compartment, indicating accelerated cartilage degeneration. KEY POINTS: • Popliteomeniscal fascicle lesions are a common finding in subjects with ACL tears. • Progression to a meniscal tear over 2 years is not frequent. • Anteroinferior popliteomeniscal fascicle is injured most frequently. • Patients with popliteomeniscal fascicle lesions showed accelerated cartilage degeneration.