Avascular necrosis and bone marrow edema syndrome
Section snippets
Definition
Osteonecrosis refers to bone death secondary to interruption of its blood supply. The term avascular necrosis describes the occurrence of osteonecrosis in the epiphysis. When the same process involves the metaphysis or diaphysis the term bone infarct is applied.
Cause and pathogenesis
The most common cause of AVN is trauma [11]. In the hip, AVN in the setting of trauma typically occurs as a complication of a displaced femoral neck fracture or hip dislocation. The risk of AVN is related to the degree of fracture
Bone marrow edema syndrome
A pattern of bone marrow edema (low signal intensity on T1-weighted images, high signal intensity on T2-weighted images) that involves the femoral head and neck has been described in several conditions. These include transient osteoporosis (TO) of the hip (bone marrow edema syndrome), epiphyseal stress fracture, infection, and osteonecrosis. There is some overlap between the imaging features of these conditions. When the clinical history and specific patient demographics are considered,
Summary
MR imaging is the most accurate modality for the diagnosis of AVN [98], [99], [100], bone marrow edema syndrome, and femoral head insufficiency fractures. When the particular demographics of the patient are considered, the specificity of this examination is high.
The reported success rates of joint-sparing operative intervention are variable. When compared with conservative management, the outcome of joint-sparing operative intervention in patients who have early (stage I, II) AVN lesions is
References (100)
- et al.
Early results in the treatment of avascular necrosis of the femoral head with electrical stimulation
Orthop Clin North Am
(1984) Mechanism of ischemic necrosis
Orthop Clin North Am
(1985)- et al.
The importance of increased intraosseous pressure in the development of osteonecrosis of the femoral head: implications for treatment
Orthop Clin N Am
(1985) Is avascular necrosis of the femoral head the result of inhibition of angiogenesis?
Med Hypotheses
(1997)- et al.
The natural history of the silent hip in bilateral atraumatic osteonecrosis
J Arthroplasty
(1993) - et al.
Primary total hip arthroplasty in systemic lupus erythematous
J Arthroplast
(1992) - et al.
Transient osteoporosis may represent a reversible early form of avascular necrosis of the hip joint
Curr Orthop
(1997) - et al.
The pattern of bone marrow oedema on MRI in osteonecrosis of the femoral head
JBJS
(2000) - et al.
Transient osteoporosis:transient bone marrow edema?
Radiology
(1988) - et al.
Radiographically negative avascular necrosis: detection with MR imaging
Radiology
(1988)