Presentation
Severe right knee pain and swelling. No history of trauma
Patient Data
Age: 70 years old
Gender: Male
From the case:
Spontaneous osteonecrosis of the knee (SONK)
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Info
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Extensive bone marrow edema of the medial femoral condyle exhibiting bright STIR signal and associated with linear subchondral fracture of the weight bearing surface of the femur displaying low signal in all pulse sequences as well as subtle flattening of the medial femoral condyle and joint effusion.
Diagnosis: Spontaneous osteonecrosis of knee stage II (MRI features)
Case Discussion
Differential diagnosis includes
- osteochondritis dessicans
- osteoarthritis and
- stress fracture
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