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Congenital talipes equinovarus (CTEV), also known as clubfoot, is a common musculoskeletal entity that affects one to two per 1000 live births worldwide. Imaging modalities including radiography, US, and MRI have emerged as valuable tools for the diagnosis, treatment, and monitoring of CTEV. The deformity is characterized by midfoot cavus, forefoot adductus, and hindfoot varus and equinus. The Ponseti method of manipulation and serial casting is the standard treatment of CTEV. Radiography shows the anatomy, position, and relationships of the different bones of the foot. US allows accurate assessment of cartilaginous and bony structures, in addition to its inherent advantages such as absence of ionizing radiation exposure. One of the indications for US is to monitor the response to Ponseti method treatment. MRI enables visualization of bones, cartilage, and soft tissues and allows multiplanar evaluation of deformities, providing a comprehensive imaging analysis of CTEV. An integrated approach that combines clinical examination and imaging findings is essential for effective management of CTEV. The authors provide a comprehensive overview of CTEV with a review of imaging modalities to help evaluate CTEV, focusing on radiography, US, and MRI. Using this article as a guide, radiologists involved in the assessment and treatment of CTEV can contribute to the management of the condition. ©RSNA, 2024 Supplemental material is available for this article.
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Pie Equinovaro , Pie Equinovaro/diagnóstico por imagen , Pie Equinovaro/terapia , Humanos , Imagen por Resonancia Magnética/métodos , Recién Nacido , LactanteRESUMEN
With an increasing life expectancy of global human population, there is a growing demand for preservation of native articular meniscus and cartilage to delay joint arthroplasties, especially in younger and active patients. Since damage to the meniscus and hyaline cartilage of the knee have limited intrinsic capacity to heal, such lesions lead to premature and/or accelerated osteoarthritis. However, knee surgical treatments have evolved and may allow restoration of the natural anatomy, delay the progression of damage, and alter the biology of the meniscus and articular cartilage. The knee preservation surgery is aided by timely detection of such injuries and high-resolution illustration and characterization of the pathology using two-dimensional and three-dimensional magnetic resonance imaging (MRI), made possible due to better MR scanner technology and related software improvements. This article reviews the current literature and authors' experience with imaging concepts and high-resolution MR imaging techniques as they relate to management and planning for such restorative procedures. Relevant arthroscopy correlations have been illustrated.
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Cartílago Articular , Menisco , Humanos , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Imagen por Resonancia Magnética , Imagenología TridimensionalRESUMEN
The Neuropathy Score Reporting and Data System (NS-RADS) is a newly developed MR imaging-based classification that standardizes reporting and multidisciplinary communication for MR imaging diagnosis and follow-up of peripheral neuropathies. NS-RADS classification has shown to be accurate and reliable across different centers, readers' experience levels, and degrees of peripheral neuropathies, which include nerve injury, entrapment, neoplasm, diffuse neuropathy, post-interventional status, and temporal changes in muscle denervation. This article brings a practical review of NS-RADS classification, representative MR cases, and a step-by-step tutorial on how to approach this staging system. Readers can gain knowledge and apply it in their practice, aiming to standardize the communications between specialties and improve patient management.
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Enfermedades del Sistema Nervioso Periférico , Humanos , Enfermedades del Sistema Nervioso Periférico/diagnóstico por imagen , Imagen por Resonancia MagnéticaRESUMEN
Imaging examinations are a fundamental part of assessing chronic lateral ankle instability (CLAI). Plain radiographs are used in the initial examination, whereas stress radiographs can be requested to actively search for instability. Ultrasonography (US) and Magnetic Resonance Imaging (MRI) allow direct visualization of ligamentous structures, with the advantage of dynamic evaluation for US, and assessment of associated lesions and intra-articular abnormalities for MRI, which plays an essential role in surgical planning. This article reviews imaging methods to diagnose and follow up on CLAI, along with illustrative cases and an algorithmic approach.
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Inestabilidad de la Articulación , Ligamentos Laterales del Tobillo , Humanos , Tobillo , Estudios Retrospectivos , Articulación del Tobillo/cirugía , Radiografía , Ligamentos Laterales del Tobillo/cirugía , Imagen por Resonancia Magnética/métodos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/cirugíaRESUMEN
The purpose of this review is to describe the anatomy and lesions affecting the peripheral portion of posterior horn of medial menisci (ramp lesions), along with illustrations and MRI cases. We will correlate imaging features with arthroscopic classification of ramp lesions. Also, postoperative and chronic changes related to meniscocapsular tears will be presented, as well as biomechanical consequences and treatment approach.
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Giant axonal neuropathy (GAN) is a severe and rare autosomal recessive neurodegenerative disorder of childhood affecting both the peripheral and central nervous systems (CNS). It is caused by mutations in the GAN (gigaxonin) gene linked to chromosome 16q24. Here, we present a 15-year-old male patient with GAN from a consanguineous family of Poonch, Jammu and Kashmir (J&K)-India. Whole-exome sequencing (WES) was employed to unravel the genetic cause of GAN in the proband. Pathogenic variant identified with WES was confirmed in other affected sibling using Sanger sequencing. Magnetic resonance imaging (MRI) and detailed clinical investigation was also carried out on proband. WES revealed a novel homozygous stopgain GAN mutation (NM_022041, c.C1028G, p.S343X) in the patient. MRI of brain displayed bilateral symmetrical confluent areas of deep white matter signal changes affecting periventricular regions (with sparing of subcortical U-fibers), posterior limbs of internal capsules, thalami, external capsules, and semioval centers. The patient was initially suspected to be a case of metachromatic leukodystrophy. However, WES analysis revealed a pathogenic variant in GAN gene as causative. No other pathogenic variant relevant to any other type of dystrophy was reported in WES. Our findings extend the geographical distribution of GAN to even a very remote region in India, extend the mutational and imaging spectrum of GAN and substantiate the need for introducing genetic testing and counselling in primary referral centers/district hospitals in India.
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Proteínas del Citoesqueleto/genética , Predisposición Genética a la Enfermedad , Neuropatía Axonal Gigante/genética , Adolescente , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Cromosomas Humanos Par 16/genética , Consanguinidad , Neuropatía Axonal Gigante/diagnóstico por imagen , Neuropatía Axonal Gigante/fisiopatología , Humanos , India/epidemiología , Masculino , Mutación/genética , Polimorfismo de Nucleótido Simple/genética , Secuenciación del ExomaRESUMEN
Spinal pain due to facet joint disease is difficult to diagnose since the clinical history and physical examination findings are usually nonspecific. Facet joint disorders have a wide range of causes and, because of the potential for chronic back pain and disability, an accurate diagnosis is essential. The most frequent cause of pain in facet joints is osteoarthritis, which can be assessed at radiography, CT, or MRI. Ganglion and synovial cysts of the facet joints can cause compressive symptoms of adjacent structures, especially radiculopathy, lower back pain, and sensory or motor deficits. In ankylosing spondylitis, imaging findings of the facet joints are useful not only for diagnosis but also for monitoring structural changes. In septic arthritis of the facet joints, an early diagnosis at MRI is essential. Gout and metabolic diseases are best evaluated at dual-energy CT, which allows the depiction of crystals. Traumatic dislocations of facet joints are usually unstable injuries that require internal reduction, fixation, and fusion and can be well assessed at CT with three-dimensional reconstructions. Facet joint neoplasms like osteoid osteoma, plasmacytoma, tenosynovial giant cell tumor, and osteochondroma are best evaluated at CT or MRI. The authors provide an overview of key imaging features of the most common facet joint disorders along with anatomic tips and illustrative cases. Acknowledging key imaging findings for the differential diagnosis of facet joint disorders plays a crucial role in the diagnostic accuracy and proper treatment approach for such entities. Online supplemental material is available for this article. ©RSNA, 2021.
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Dolor de la Región Lumbar , Articulación Cigapofisaria , Dolor de Espalda , Diagnóstico Diferencial , Humanos , Columna Vertebral , Articulación Cigapofisaria/diagnóstico por imagenRESUMEN
Magnetic resonance neurography is a high-resolution imaging technique that allows evaluating different neurological pathologies in correlation to clinical and the electrophysiological data. The aim of this article is to present a review on the anatomy of the lumbosacral plexus nerves, along with imaging protocols, interpretation pitfalls, and most common pathologies that should be recognized by the radiologist: traumatic, iatrogenic, entrapment, tumoral, infectious, and inflammatory conditions. An extensive series of clinical and imaging cases is presented to illustrate key-points throughout the article.
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Plexo Lumbosacro/diagnóstico por imagen , Plexo Lumbosacro/patología , Imagen por Resonancia Magnética , Humanos , Desnervación MuscularRESUMEN
PURPOSE: To determine if posterior cruciate ligament (PCL) and intercondylar notch (IN) morphometries and volumetrics act as risk factors for anterior cruciate ligament (ACL) tears. METHODS: A prospective case-controlled magnetic resonance imaging (MRI) study was conducted with subjects presenting noncontact knee injuries. Exclusion criteria were previous surgery, PCL tear, osteoarthritis, tumors, or infectious and inflammatory conditions. All participants underwent a flexed-knee 3-dimensional (3D) magnetic resonance imaging (MRI) to uniformly straighten PCL. MR images were independently reviewed by 2 radiologists and assessed for 2D and 3D measurements (bicondylar width; IN angle, depth, width, and cross-sectional area; PCL width, thickness, and cross-sectional area; and IN and PCL volumes). Clinical profiles were tabulated and subjects were divided into cases (ACL tear) and controls (without ACL tear). RESULTS: The study was composed of 50 cases versus 52 controls (N = 102), with a mean age of 36.8 years. There was no difference between groups (P > .05) regarding age, gender, body mass index, time from injury, Tegner score, flexion angle, limb side, intensity of injury, or familial or opposite limb history of tear. Agreement between readers ranged from substantial to almost perfect. Subjects with ACL tear presented with lower IN width, lower IN minus PCL widths, lower Notch Width Index, higher PCL/IN width proportion, higher PCL thickness, lower IN depth minus PCL thickness, and higher PCL thickness/IN depth proportion (P < .05). Moreover, higher PCL/IN cross-sectional area proportion, higher PCL volumes (OR = 9.01), and higher PCL/IN volume proportion were also found in cases. CONCLUSIONS: Our study shows that subjects with ACL tears present not only reduced IN but also larger PCL dimensions. These findings, isolated and combined, and especially PCL volume, might be suggestive as risk factors for ACL tears owing to the reduction of its space inside the IN. LEVEL OF EVIDENCE: Level III, comparative group.
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Lesiones del Ligamento Cruzado Anterior/patología , Ligamento Cruzado Anterior/patología , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Ligamento Cruzado Posterior/patología , Adolescente , Adulto , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/cirugía , Estudios de Casos y Controles , Femenino , Humanos , Articulación de la Rodilla/fisiopatología , Masculino , Persona de Mediana Edad , Ligamento Cruzado Posterior/cirugía , Estudios Prospectivos , Rango del Movimiento Articular , Factores de Riesgo , Rotura , Adulto JovenRESUMEN
PURPOSE: This study aims to describe a technique for in-plane ultrasound-guided knee arthrography through a lateral suprapatellar approach, reporting its accuracy and related complications. METHODS: A retrospective search was performed for computed tomography and magnetic resonance reports from June 2013 through June 2015. Imaging studies, puncture descriptions, and guided-procedure images were reviewed along with clinical and surgical history. A fellowship-trained musculoskeletal radiologist performed all procedures under sterile technique and ultrasound guidance with the probe in oblique position on the lateral suprapatellar recess after local anesthesia with the patient on dorsal decubitus, hip in neutral rotation, and 30 to 45 degrees of knee flexion. RESULTS: A total of 86 consecutive subjects were evaluated (mean, 55 years). All subjects underwent intra-articular injection of contrast, which was successfully reached in the first attempt in 94.2% of the procedures (81/86), and in the second attempt in 5.8% (5/86) after needle repositioning without a second puncture. There were no postprocedural reports of regional complications at the puncture site, such as significant pain, bleeding, or vascular lesions. CONCLUSIONS: Our study demonstrates that in-plane ultrasound-guided injection of the knee in semiflexion approaching the lateral suprapatellar recess is a safe and useful technique to administer intra-articular contrast solution, as an alternative method without radiation exposure.
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Corticoesteroides/administración & dosificación , Medios de Contraste/administración & dosificación , Inyecciones Intraarticulares/métodos , Articulación de la Rodilla/diagnóstico por imagen , Rótula/diagnóstico por imagen , Ultrasonografía Intervencional/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
OBJECTIVE: To evaluate the diagnostic yield of two acquisitions of single-contrast CT arthrography (CTA) of the shoulder in internal, neutral, or external glenohumeral rotation with arthroscopic correlation. MATERIALS AND METHODS: The CT study was obtained using two acquisitions (first the humerus positioned in maximum tolerated external rotation with the arm along the body and the second with the humerus in internal rotation with the palm placed flat on the table). Two independent readers blinded to the arthroscopic results evaluated the CTA images for labral tears, glenoid bone loss/fractures, and cartilage loss. For each CTA acquisition, sensitivity and specificity for detection of the aforementioned pathology were assessed. Inter-reader agreement was quantified by weighted ĸ statistics. RESULTS: Sensitivity and specificity for detecting anteroinferior or posterior labral tears was highest with neutral rotation (sensitivity 91-100%, specificity 61-100%). For glenoid fracture, sensitivity (67%) was highest with external rotation and specificity (100%) was highest with internal rotation. For cartilage loss, sensitivity (64%) and specificity (89%) was highest with external rotation and neutral rotation, respectively. Neutral rotation showed high sensitivity and specificity for glenoid fractures and cartilage loss. Inter-reader agreement ranged from fair to very good. CONCLUSIONS: Neutral glenohumeral position in shoulder CT arthrography was adequately sensitive and specific for the detection of intra-articular pathology, avoiding the use of more than one acquisition.
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Artrografía/métodos , Artroscopía , Posicionamiento del Paciente/métodos , Articulación del Hombro/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Articulación del Hombro/cirugía , Adulto JovenAsunto(s)
Aneurisma Falso/diagnóstico por imagen , Artralgia/diagnóstico por imagen , Neoplasias Femorales/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Osteocondroma/diagnóstico por imagen , Arteria Poplítea/diagnóstico por imagen , Adolescente , Aneurisma Falso/complicaciones , Artralgia/etiología , Neoplasias Femorales/complicaciones , Humanos , Imagen por Resonancia Magnética , Masculino , Osteocondroma/complicaciones , RadiografíaRESUMEN
BACKGROUND: Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is commonly performed for cancer staging, as it can detect metastatic disease in multiple organ systems. However, there has been some controversy in the scientific literature when comparing FDG PET/CT and technetium-99 m-bone scintigraphy (bone scan) for the detection of skeletal metastases. PURPOSE: To compare the accuracy of FDG PET/CT with bone scan for the detection of skeletal metastases. MATERIAL AND METHODS: The study group comprised 202 adult cancer patients who underwent both FDG PET/CT and bone scan within 31 days for staging. Bone scans and FDG PET/CT were evaluated by two musculoskeletal radiologists for the presence and location of skeletal metastatic disease. Confirmation of the final diagnosis was based on the CT or magnetic resonance imaging (MRI) appearance, follow-up imaging, or histology. RESULTS: The sensitivity, specificity, and accuracy for detecting skeletal metastatic disease of FDG PET/CT were 97%, 98%, and 98%, respectively, and of bone scan were 83%, 98%, and 93%, respectively. The lesions that bone scan most commonly missed were located in the pelvis, spine, and sacrum. FDG PET/CT missed mostly lesions that were outside of the field of view, but in all of these cases the patient had additional sites of skeletal metastatic disease. Bone scan falsely identified six metastatic lesions and FDG PET/CT falsely identified three metastatic lesions. CONCLUSION: FDG PET/CT is an accurate technique for detection of skeletal metastases, and is superior to bone scan, especially in the spine and pelvis.
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Neoplasias Óseas/secundario , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/diagnóstico por imagen , Niño , Femenino , Fluorodesoxiglucosa F18 , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Radiofármacos , Sensibilidad y Especificidad , Medronato de Tecnecio Tc 99mRESUMEN
OBJECTIVE: The purpose of this study was to determine whether there is a difference in biopsying bone (endplate), disk, or paravertebral soft tissue to culture the pathogenic organism causing diskitis-osteomyelitis. MATERIALS AND METHODS: A retrospective review was conducted of 111 spinal biopsies performed between 2002 and 2011. Pathologic examination was used as the reference standard for detecting diskitis-osteomyelitis. Microbiologic yield, sensitivity, and specificity were calculated. The yields for different groups were compared by use of Fisher exact test. The analysis was repeated with biopsy samples from patients not being treated with antibiotics at the time of biopsy. RESULTS: A total of 122 biopsy specimens were obtained from 111 spinal biopsy procedures on 102 patients. Overall, 27 (22%) biopsies were performed on the endplate-disk, 61 (50%) on the disk only, and 34 (28%) on paravertebral soft tissue only. The microbiologic yield was 36% for all biopsies, 19% for endplate-disk biopsies, 39% for disk-only biopsies, and 44% for soft-tissue biopsies. The sensitivity and specificity of the microbiologic results for all specimens were 57% and 89%; endplate-disk, 38% and 86%; disk only, 57% and 89%; and paravertebral soft tissue, 68% and 92%. There was no statistically significant difference between the yields of the endplate-disk, disk-only, and paravertebral soft-tissue biopsies. CONCLUSION: Paravertebral soft-tissue changes, when present, may be considered a viable target for biopsy in cases of diskitis-osteomyelitis, even in the absence of a paravertebral abscess.
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Discitis/patología , Biopsia Guiada por Imagen , Osteomielitis/patología , Enfermedades de la Columna Vertebral/patología , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Discitis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteomielitis/diagnóstico por imagen , Estudios Retrospectivos , Sensibilidad y Especificidad , Enfermedades de la Columna Vertebral/diagnóstico por imagenRESUMEN
OBJECTIVE: Evaluate the visibility and describe the anatomical features of the anterolateral ligament of the knee using MRI. MATERIALS AND METHODS: Magnetic resonance imaging examinations of the knee were independently reviewed by two musculoskeletal radiologists and assessed for the visibility of the anterolateral ligament under direct cross-referencing of axial and coronal images as complete, partial, or non-visible. Distal insertion site (tibial, meniscal), distance to lateral tibial plateau, measurements (length, width, thickness), and associated imaging findings were also tabulated. Clinical and surgical records were also reviewed. RESULTS: Seventy MRI scans from 60 consecutive subjects were included in the study. Mean age was 40 years, body mass 74.9 kg, and height 1.72 m. The subject population was 53% male, most of the knees were from the left side (51%), and chronic pain was the main clinical symptom (40%). Nine knees (13 %) had undergone previous surgery. The anterolateral ligament was identified in 51% of the knees: completely visible in 11% and partially visible in 40%. In all visible cases, the distal insertion site was identified on the tibia, with a mean distance of 5.7 mm to the plateau. A completely visible ligament had a mean length of 33.2 mm, width of 5.6 mm, and thickness of 1.9 mm [corrected]. Inter-observer agreement for ligament presence was significant (κ = 0.7). Statistical analyses showed a trend to be more visible in men, with a longer length compared with women. CONCLUSIONS: Magnetic resonance imaging clearly identifies the anterolateral ligament of the knee in slightly more than half of cases, being partially visible in most of them. In all cases, a tibial insertion is characterized.
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Puntos Anatómicos de Referencia/anatomía & histología , Ligamentos Colaterales/anatomía & histología , Articulación de la Rodilla/anatomía & histología , Imagen por Resonancia Magnética/métodos , Tibia/anatomía & histología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto JovenAsunto(s)
Artritis Infecciosa/diagnóstico por imagen , Candida albicans/aislamiento & purificación , Candidiasis/diagnóstico , Fungemia/diagnóstico , Articulación de la Cadera , Osteomielitis/diagnóstico por imagen , Anciano , Artritis Infecciosa/complicaciones , Artritis Infecciosa/terapia , Candidiasis/terapia , Progresión de la Enfermedad , Resultado Fatal , Fungemia/tratamiento farmacológico , Humanos , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/terapia , Masculino , Osteomielitis/complicaciones , Osteomielitis/terapia , Tomografía de Emisión de Positrones/métodos , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Tomografía Computarizada por Rayos X/métodosRESUMEN
OBJECTIVE: The purpose of this article is to describe the MRI features of rotator cuff myotendinous junction injuries. MATERIALS AND METHODS: We retrospectively identified MRI cases with myotendinous junction injury of the rotator cuff muscles and reviewed clinical, imaging, and surgical records. MR images were reviewed independently by two musculoskeletal radiologists to grade myotendinous junction injuries (strain, partial tear, or complete tear) and to assess for concurrent tendon tears (partial or full thickness) and bone changes (fracture or contusion). RESULTS: The final study group comprised 16 subjects. The mean age was 38 years, with a majority of men (56%). The left shoulder was affected in 56% of subjects, with the dominant upper limb affected in 50%. The mean time between symptoms and MRI was 19 days. Subjects reported heavy lifting (19%), landing on the arm after a fall (19%), or prior shoulder therapeutic injection (25%). Myotendinous junction injuries affected the infraspinatus muscle (50%), followed by the supraspinatus (31%), subscapularis (25%), and teres minor (19%) muscles. About one fifth of subjects presented with more than one muscle affected, and 94% did not present with tears of the corresponding tendons. Most myotendinous junction injuries were strains (80%), followed by partial tears (20%). No complete tears were identified. There was no correlation between myotendinous junction injury and the presence of bone changes or the presence of tendon tears (p > 0.05). CONCLUSION: Rotator cuff myotendinous junction injuries affect mostly the infra-spinatus and supraspinatus muscles, usually in a strain pattern and without tear of the corresponding tendon attachment.
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Imagen por Resonancia Magnética/métodos , Lesiones del Manguito de los Rotadores , Rotura/diagnóstico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosAsunto(s)
Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/patología , Neuropatía Ciática/complicaciones , Neuropatía Ciática/patología , Intento de Suicidio , Adulto , Medios de Contraste , Diagnóstico Diferencial , Humanos , Aumento de la Imagen/métodos , Plexo Lumbosacro/patología , Imagen por Resonancia Magnética/métodos , Masculino , Nervio Ciático/patologíaRESUMEN
We report a rare case of Kager's fat pad atrophy and fibrosis in a 60-year-old woman 1 year after a steroid injection for Achilles tendinopathy. There are few published reports of steroid-induced atrophy affecting deeper layers of fat tissue. To our knowledge, this case report is the first to illustrate its features using magnetic resonance imaging. A review of the scientific literature is also presented.