[Bone infarctions-from pathophysiology to imaging].

backgroundBone infarctions are a relatively understudied subgroup of osteonecroses in the literature. As frequently incidental, yet distinct imaging findings, they must be interpreted in the context of predisposed patient groups, relevant risk factors, differential diagnoses, and potential complications.

objectiveTo present the interrelationship of pathophysiology with imaging, as well as the clinical courses, histopathological correlates, and diagnostic challenges. MATERIALS AND

methodsLiterature research over the past three decades on epidemiology, pathophysiology, risk factors, and the clinical spectrum with pertinent implications for imaging (plain radiography, computed tomography [CT], magnetic resonance imaging [MRI]).

resultsBone infarctions manifest in the meta-/diaphyses of long bones and are frequently multifocal. Robust epidemiological data are lacking. Clinically, they present with acute, painful courses in systemic diseases or as oligosymptomatic incidental imaging findings. Imaging reflects the pathophysiology. Plain radiography is in general sufficient for diagnosis in late stages, whereas MRI provides the highest diagnostic accuracy.

conclusionAlthough often an "Aunt Minnie" in imaging, bone infarctions should be understood as a systemic condition. Differentiation from acute osteomyelitis and the rare risk of malignant transformation represent major clinical and diagnostic challenges.