RESUMEN
Myositis ossificans is a benign disorder characterized by the formation of heterotopic bone in skeletal muscle or soft tissues. It is extremely rare in children, <1% of cases occur in children under 10 years. We present a 17-day-old boy that, after 10 days of Intermediate Care Unit stay, was referred to our hospital for a developmental dysplasia of the hip. On clinical examination, he had swelling on the left thigh and increase in size compared to the contralateral one, therefore was admitted for studying. Imaging findings including plain radiographs, CT, MRI and bone scintigraphy, as well as treatment performed, are described. To the best of our knowledge, is the youngest case reported in the literature.
RESUMEN
Myositis ossificans is a self-limiting, benign ossifying lesion that can affect any type of soft tissue, including subcutaneous fat, tendons, and nerves. It is most commonly found in muscle as a solitary lesion. Ossifying soft-tissue lesions historically have been inconsistently classified. Fundamentally, myositis ossificans can be categorized into nonhereditary and hereditary types, with the latter being a distinct entity with a separate pathophysiology and treatment approach. The etiology of myositis ossificans is variable; however, clinical presentation generally is characterized by an ossifying soft-tissue mass. Advanced cross-sectional imaging alone can be nonspecific and may appear to be similar to more sinister etiologies. Therefore, the evaluation of a suspicious soft-tissue mass often necessitates multiple imaging modalities for accurate diagnosis. When imaging is indeterminate, biopsy may be required for a histologic diagnosis. However, histopathology varies based on stage of evolution. The treatment of myositis ossificans is complex and is often made in a multidisciplinary fashion because accurate diagnosis is fundamental to a successful outcome.
Asunto(s)
Miositis Osificante/diagnóstico , Neoplasias de los Tejidos Blandos/diagnóstico , Biopsia , Diagnóstico Diferencial , Diagnóstico por Imagen/métodos , Humanos , Miositis Osificante/patología , Neoplasias de los Tejidos Blandos/patologíaRESUMEN
Myositis ossificans is a rare cause of trismus. We present a case of pseudomalignant myositis ossificans involving medial pterygoid, lateral pterygoid, and temporalis muscles. Patient presented with gross limitation in mouth opening. There was no history of trauma. Computed tomography (CT) images revealed a bone density mass located in the region of medial and lateral pterygoid muscles on the right and temporalis muscle on the left. Magnetic resonance imaging (MRI) showed similar findings. Radiological diagnosis was pseudomalignant myositis ossificans. The masses were resected and histopathologic examination confirmed the above diagnosis. This report describes the characteristic CT and MRI features. The unique feature of this case is the absence of history of trauma with involvement of multiple masticatory muscles, which, to the best of our knowledge, has not been reported before.