Mobile encapsulated fat necrosis
Mobile encapsulated fat necrosis is a rare medical condition featuring the formation of a fibrotic capsule around a small, necrotic mass of fatty tissue. It is asymptomatic and benign but may be mistaken for other neoplasms due to its typical presentation as a firm nodule beneath the skin that can be moved around within the tissue. MEFN lesions frequently arise near joints on the arms and legs following trauma, especially the elbow. Many cases also appear even without any known injury.
MEFN lesions tend to go unnoticed for many years, due to their asymptomatic nature and relatively small size, usually being somewhat flattened and no more than 1–2 cm in diameter. Once noticed, they are often surgically removed, even in cases where this exceedingly rare condition is successfully identified by a physician familiar with it, because this procedure is minimally invasive and ensures that the MEFN lesion is not a more dangerous tumor.