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Bone infarction refers to ischemic necrosis of medullary (trabecular) bone and marrow, typically due to compromised blood supply, without involvement of the subchondral bone (which would be called avascular necrosis [AVN]).
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Types of bone infarction:
| Type | Location | Example |
|---|---|---|
| Epiphyseal infarct | Subchondral region → AVN | Femoral head necrosis |
| Metaphyseal/diaphyseal infarct | Medullary infarct | Common in sickle cell anemia |
| Category | Causes |
|---|---|
| Hematologic | Sickle cell disease, thalassemia, polycythemia vera |
| Traumatic | Fracture disrupting vascular supply |
| Iatrogenic | Corticosteroid therapy, chemotherapy, radiation |
| Metabolic | Gaucher disease, pancreatitis |
| Idiopathic | Often no clear cause |
| Decompression | Caisson disease (diving-related; nitrogen emboli) |
| Symptom | Description |
|---|---|
| Bone pain | Localized, worsened with activity |
| Swelling/tenderness | May occur in acute infarcts |
| Asymptomatic | Chronic or incidental finding |
| Systemic signs | If associated with SCD or systemic disease |
Common locations:
| Frequent Sites | Examples |
|---|---|
| Long bones | Femur, tibia, humerus |
| Ribs, vertebrae | In SCD-related infarctions |
| Pelvis | Iliac wings, acetabular region |
http://dx.doi.org/10.17727/JMSR.2021/9-17
| Modality | Imaging features |
|---|---|
| XR | May be normal in early stages (takes weeks to show) |
| • Medullary calcification | |
| • Serpiginous sclerotic border (wavy or “snake-like” outline) | |
| • Patchy lucencies and sclerosis | |
| • No subchondral collapse (unlike AVN) | |
| CT | • Shows serpiginous medullary sclerosis, helpful in late-stage infarct |
| • Cortical changes or fractures in complicated cases | |
| MR | • T1: Central low signal with peripheral serpiginous hyperintensity |
| • T2/STIR: Central high signal with serpiginous hypointense rim | |
| • ‣ : Inner high + outer low signal rim on T2 (specific to infarction) | |
| • Enhancement: Peripheral contrast enhancement if active or subacute | |
| Bone scan | Bone scan (Tc-99m MDP): |
| • Cold defect early (vascular occlusion) | |
| • May become hot later due to reactive changes or healing |
Radiographs of knee showing areas of lucency (red arrow), surrounded by serpiginous sclerosis (yellow arrow) in the medullary cavity of the distal metaphysis of femur. Decreased medial tibiofemoral joint space is also noted.
Pai S, Sathish Muthu, Naveen Jeyaraman, Madhan Jeyaraman. Multiple bone infarcts with intra-articular extension. BMJ Case Reports. 2022;15(3):e249164-e249164. doi:https://doi.org/10.1136/bcr-2022-249164
MRI of the knee. (A) T1 weighted sagittal section showing hypointense lesions (red arrows) in the distal end of femur and proximal end of tibia. Classical ‘smoke up the chimney’ appearance of the lesion. Lesion in the proximal tibia seen extending till articular surface. (B) T2 weighted sagittal section showing periphery of the lesion representing the regions of sclerosis (yellow arrow) to be hyperintense. (C) T1 weighted coronal section showing the central portion of the lesions (blue arrow) to have signal similar to that of normal marrow, while the periphery of the lesion is hypointense (green arrow). (D) T2 weight coronal section showing the sclerotic region to be hyperintense (orange arrow). The distal femoral lesion is seen extending till the articular surface. (E and F) Axial sections showing hypointense lesions (pink arrows) in proximal tibia and distal femur, respectively.
Pai S, Sathish Muthu, Naveen Jeyaraman, Madhan Jeyaraman. Multiple bone infarcts with intra-articular extension. BMJ Case Reports. 2022;15(3):e249164-e249164. doi:https://doi.org/10.1136/bcr-2022-249164
| Condition | Key Differences |
|---|---|
| ‣ | Subchondral involvement, articular collapse, location near joint surface |
| Osteomyelitis | Fever, elevated inflammatory markers, marrow enhancement + abscess |
| Enchondroma | Central lucency, chondroid matrix, no serpiginous sclerosis |
| Bone metastasis | Ill-defined, destructive, soft tissue component |