From the Radiologic Pathology Archives Imaging of Osteonecrosis: Radiologic-Pathologic Correlation

Abstract

Osteonecrosis is common and represents loss of blood supply to a region of bone. Common sites affected include the femoral head, humeral head, knee, femoral/tibial metadiaphysis, scaphoid, lunate, and talus. Symptomatic femoral head osteonecrosis accounts for 10,000-20,000 new cases annually in the United States. In contradistinction, metadiaphyseal osteonecrosis is often occult and asymptomatic. There are numerous causes of osteonecrosis most commonly related to trauma, corticosteroids, and idiopathic. Imaging of osteonecrosis is frequently diagnostic with a serpentine rim of sclerosis on radiographs, photopenia in early disease at bone scintigraphy, and maintained yellow marrow at MR imaging with a serpentine rim of high signal intensity (double-line sign) on images obtained with long repetition time sequences. These radiologic features correspond to the underlying pathology of osseous response to wall off the osteonecrotic process and attempts at repair with vascularized granulation tissue at the reactive interface. The long-term clinical importance of epiphyseal osteonecrosis is almost exclusively based on the likelihood of overlying articular collapse. MR imaging is generally considered the most sensitive and specific imaging modality both for early diagnosis and identifying features that increase the possibility of this complication. Treatment subsequent to articular collapse and development of secondary osteoarthritis typically requires reconstructive surgery. Malignant transformation of osteonecrosis is rare and almost exclusively associated with metadiaphyseal lesions. Imaging features of this dire sequela include aggressive bone destruction about the lesion margin, cortical involvement, and an associated soft-tissue mass. Recognizing the appearance of osteonecrosis, which reflects the underlying pathology, improves radiologic assessment and is important to guide optimal patient management.

Downregulated SOX9 mediated by miR‑206 promoted cell apoptosis in Legg-Calv�-Perthes disease

“…Study confirmed that boys diagnosed with LCPD was much more than girls (2). The clinical presentation of the early stage is the painful synovitis in the knees, and the follow-up symptoms presented that the femoral head ossific nuclei of LCPD are much smaller than those normal children with similar age, which made the traversing blood vessels are more vulnerable (3). The prognosis of LCPD in early onset is optimistic, while the treatment for advanced LCPD had poor outcome.…”

A Condition Confused with Complex Regional Pain Syndrome in Hemiplegia: Simultaneous Occurance of Knee Osteonecrosis and Monoarthritis

“…7 Mitchell et al has developed a classification system for ON, according to the signal characteristics within the center of the osteonecrotic lesion. 8 In this case report, the MRI findings of lesions were compatible with class B signal intensity (high intensity in T1 and T2 sequences).…”

Differential proteomic screening and identification for non-traumatic necrotic femoral osseous tissue

“…In combination with results from existing research on femoral head necrosis and the many pathogenesis doctrines [blood hypercoagulability state (22), lipid metabolism disorders (23), and metabolic disorders of oxygen-free radicals (24)], it can be inferred that the expression levels of most fibrinogens are upregulated in the advanced stage of femoral head necrosis due to blood hypercoagulability in the elderly patients. Lipid metabolism disorders, fat deposition in the femoral head, and the fat-occluded vessels lead to avascular necrosis.…”