Presentation
Recent increase of right knee pain. No trauma.
Patient Data
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 .