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Subchondral insufficiency fracture of the knee

Case contributed by Dr Dalia Ibrahim


Recent increase of right knee pain. No trauma.

Patient Data

Age: 70 years
Gender: Male

The medial femoral condyle is flattened and shows a subchondral irregular line of persistent low signal, surrounded by extensive marrow edema signal of the medial femoral condyle.

Patello-femoral and femorotibial knee osteoarthritis with chondromalacia patellae.

Lateral femoral condyle osteochondral injury with subchondral marrow edema.

Degeneration of the body and posterior horn of the medial meniscus with root tear.

Mild joint effusion.

Baker's cyst with surrounding posterior knee soft tissue edema signal, which could be the sequel of ruptured Baker's cyst.

Case Discussion

Subchondral insufficiency fracture of the knee (SIF/SIFK) are stress fractures in the femoral condyles or tibial plateau that occur in the absence of acute trauma, typically affecting older adults.

The entity subsumes that previously known as spontaneous osteonecrosis of the knee (SONK/SPONK) or Ahlbäck disease.

Subchondral insufficiency fractures are a relatively common cause of knee pain, particularly in older females,in the absence of trauma or following minor trauma .

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Case information

rID: 76210
Published: 16th Apr 2020
Last edited: 17th Apr 2020
Inclusion in quiz mode: Included

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