Presentation
Chronic pain above left popliteal fossa.
Patient Data
Age: 20 years
Gender: Female
From the case:
Cortical desmoid
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Focal cortical irregularity and thickening at the posterior aspect of the medial condyle of the femur.
From the case:
Cortical desmoid
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There is evidence of extra-cortical lesion with cortical irregularity in the posteromedial aspect of left distal femur (2.2 cm in length). The lesion returns isointense signal on T2 and hypointense signal on T1 and hyperintense signal on PD fat sat sequences.
Rest of the bones are normal.
Case Discussion
The typical location and imaging features are very likely for cortical desmoid (a benign, self-limiting entity which is classified as don't touch lesion).
The less likely differential can again be a benign entity (fibrous cortical defect).