Fibrous dysplasia of the fibula

Case contributed by Dr Mohammad A. ElBeialy

Presentation

Mild knee pain.

Patient Data

Age: 19 years
Gender: Female
X-ray

Centrally located proximal fibular metadiaphyseal expansile lytic lesion with characteristic ground glass attenuation. The lesion shows thin septations. No periosteal reaction or definite pathological fracture.The lesion has narrow zone of transition and thin sclerotic margin with mild endosteal scalloping.

MRI

The proximal diametaphysis of the right fibula shows a well-defined slightly expansile multiloculated lesion measuring about 11x1.5x1.5 cm in its maximal orthogonal dimensions. No cortical breakthrough, periosteal reaction, extra-osseous components or intra-articular extension.

The lesion elicits low T1 and high T2/STIR signals. A small area of marrow edema of low T1 and high T2/STIR signals is seen in the fibular shaft related to the lower part of the lesion. No appreciable post-contrast enhancement.

Case Discussion

This case shows a typical fibrous dysplasia of the proximal fibula. Expansile lytic lesion in with ground glass attenuation is the best diagnostic clue for fibrous dysplasia. Fibrous dysplasia is described as a long disease in a long bone.

The differential diagnosis is;

  • aneurysmal bone cyst: eccentrically located lesion with typical fluid fluid levels.
  • simple bone cyst: centrally located lesion with fallen fragment sign.
  • chondromyxoid fibroma: usually around knee with predilection for the tibia; geographic pattern with bone destruction and sclerotic margin with periosteal reaction.
PlayAdd to Share

Case information

rID: 28300
Case created: 20th Mar 2014
Last edited: 25th Feb 2017
Inclusion in quiz mode: Included

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.