Measurement of tibial slope using biplanar stereoradiography (EOS®).

OBJECTIVES: Posterior tibial slope (PTS) is an important anatomic parameter of the knee related to anteroposterior instability. Biplanar stereoradiography allows for simultaneous low-dose acquisition of anteroposterior and lateral views with 3D capability, enabling separate lateral and medial plateau analyses. We aimed to evaluate the possibility and compare the reproducibility of measuring medial and lateral PTS on EOS® images with two different patient positionings and compare it with CT of the knees as the gold standard. METHODS: This is a retrospective study including volunteers who underwent lower limb stereoradiography and knee CT from 01/08/2016 to 07/31/2019. Sixty legs from 30 patients were studied. PTS were measured using stereoradiography and CT by two radiologists. Intraclass correlation was used to calculate intrarater and interrater reproducibilities. Pearson's correlation coefficients were used to calculate the correlation between stereoradiography and CT. We also compared the reproducibility of the stereoradiography of volunteers with 2 different positionings. RESULTS: The mean stereoradiography PTS values for right and left knees were as follows: lateral, 12.2° (SD: 4.1) and 10.1° (SD: 3.5); medial,12.2° (SD: 4.4) and 11.6° (SD: 3.9). CT PTS mean values for right and left knee are as follows: lateral, 10.3° (SD:2.5) and 10.6° (SD: 2.8); medial: 8.7° (SD: 3.7) and 10.4° (SD: 3.5). Agreement between CT and EOS for angles between lateral and medial PTS was good (right, 0.874; left, 0.871). Regarding patient positioning on stereoradiography, interrater and intrarater reproducibilities were greater for patients with nonparallel feet (0.738-0.883 and 0.870-0.975). CONCLUSIONS: Stereoradiography allows for appropriate delineation of tibial plateaus, especially in patients with nonparallel feet, for the purpose of measuring PTS. The main advantage is lower radiation doses compared to radiography and CT.

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.

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.

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.

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.

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.

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.

Stener-like lesions in the hand, knee and foot: a review of anatomy, mechanism of injury and imaging evaluation.

A Stener lesion is a displaced tear of the ulnar collateral ligament in the metacarpophalangeal joint of the thumb in which the adductor pollicis aponeurosis is positioned between the retracted ligament and the injury site, preventing natural healing. This lesion was first described in 1962, and since then, both radiologists and orthopedists have considered it important to treat surgically. Although this lesion was originally described in the thumb, this injury mechanism can occur in other joints of the hand, knee, and foot. The purpose of this study was to review the relevant aspects of classic Stener lesions of the thumb, as well as other Stener-like lesions, including their anatomy, mechanisms of lesion formation and imaging features. The Stener-like injury pattern often necessitates surgical repair or reconstruction; thus, it is essential that radiologists recognize and report the different patterns of injury.

The Role of Magnetic Resonance in the Diagnosis of Chronic Exertional Compartment Syndrome.

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.

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.

Estudo da articulação patelofemoral por ressonância magnética: a variação da morfologia do ligamento patelofemoral medial / Study on the patellofemoral joint using magnetic resonance imaging: morphological variation of the medial patellofemoral ligament

OBJETIVO: Estudar as medidas e relações anatômicas da articulação patelofemoral por ressonância magnética, avaliando a variação da morfologia do ligamento patelofemoral medial (LPFM) de acordo com a altura e a idade do paciente, bem como com as variações das medidas das outras estruturas reconhecidamente envolvidas na predisposição à instabilidade patelar. MÉTODO: Foram submetidos ao exame de ressonância magnética 23 joelhos (18 pacientes), sendo aferidas as medidas da distância interepicondilar, altura da patela, profundidade da tróclea, proeminência troclear ventral, ângulo do sulco da tróclea, inclinação da faceta lateral, inclinação lateral da patela, tamanho da faceta lateral e medial e sua razão, e as medidas de comprimento e espessura do LPFM, sendo essas comparadas com as demais medidas. RESULTADOS: O comprimento do LPFM foi de, em média, 46,4mm, enquanto as espessuras medidas na inserção patelar, terço médio e inserção femoral foram de, respectivamente, 1,7mm, 1,4mm e 1,2mm. A espessura do LPFM correlacionou-se positivamente com a medida do côndilo lateral e a distância interepicondilar, e negativamente com a idade do paciente. CONCLUSÃO: A morfologia do LPFM varia em função da distância interepicondilar e do côndilo lateral e da idade do paciente.

OBJECTIVES: To study the measurements and anatomical relationships of the patellofemoral joint using magnetic resonance imaging, and to evaluate the variation in the morphology of the medial patellofemoral ligament (MPFL) according to patients' heights and ages and the variation in measurements on other structures that are known to be involved in predisposition to patellar instability. METHOD: Twenty-three knees (18 patients) underwent magnetic resonance imaging and their interepicondylar distance, patellar height, trochlear depth, ventral trochlear prominence, trochlear groove angle, lateral facet tilt, lateral patellar tilt and size of the lateral and medial facets and their ratio were measured. These measurements were compared with the length and thickness of the MPFL. RESULTS: The average length of the MPFL was 46.4 mm, while the average thicknesses of its patellar insertion, middle third and femoral insertion were, respectively, 1.7 mm, 1.4 mm and 1.2 mm. The thickness of the MPFL correlated positively with the lateral condyle and interepicondylar distance measurements, and negatively with the patients' ages. Conclusion: The morphology of the MPFL varies with the interepicondylar distance and the lateral condyle distance, and with patients' ages.

STUDY ON THE PATELLOFEMORAL JOINT USING MAGNETIC RESONANCE IMAGING: MORPHOLOGICAL VARIATION OF THE MEDIAL PATELLOFEMORAL LIGAMENT.

OBJECTIVES: To study the measurements and anatomical relationships of the patellofemoral joint using magnetic resonance imaging, and to evaluate the variation in the morphology of the medial patellofemoral ligament (MPFL) according to patients' heights and ages and the variation in measurements on other structures that are known to be involved in predisposition to patellar instability. METHOD: Twenty-three knees (18 patients) underwent magnetic resonance imaging and their interepicondylar distance, patellar height, trochlear depth, ventral trochlear prominence, trochlear groove angle, lateral facet tilt, lateral patellar tilt and size of the lateral and medial facets and their ratio were measured. These measurements were compared with the length and thickness of the MPFL. RESULTS: The average length of the MPFL was 46.4 mm, while the average thicknesses of its patellar insertion, middle third and femoral insertion were, respectively, 1.7 mm, 1.4 mm and 1.2 mm. The thickness of the MPFL correlated positively with the lateral condyle and interepicondylar distance measurements, and negatively with the patients' ages. CONCLUSION: The morphology of the MPFL varies with the interepicondylar distance and the lateral condyle distance, and with patients' ages.