Presentation
Knee pain and swelling. Exclude fracture.
Patient Data
Age: 10 years
Gender: Female
From the case:
Osteosarcoma
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AP and lateral XR of the right knee shows an ill-defined lesion within the right distal femoral diaphysis and metaphysis with:
- wide zone of transition
- mixed density of lysis/sclerosis
- cortical destruction and aggressive periosteal reaction
- soft tissue mass anteriorly
- no associated pathologic fracture
From the case:
Osteosarcoma
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Aggressive bone lesion:
- T1 hypointense, T2 hyperintense, heterogeneously enhancing
- centered in the right distal femoral diaphysis and extending into the epiphysis with a circumferential subperiosteal soft tissue mass
- epiphyseal component involves the articular cortex in the intercondylar region
- joint effusion and muscular edema
- no pathological fracture
- no skip lesions
Case Discussion
Osteosarcoma was confirmed histologically. On imaging, the differential diagnosis also includes Ewing sarcoma.
Case contributed by Dr Gillian Long