Ankle Destructive Lesion-Teaching Discussion

13 yr old male with pain and swelling of the ankle for 3 months  with no history of trauma. Teaching points by Dr MGK Murthy.

How to discuss the case  and report

1)   What is the Abnormality?

Grossly destructive, expansile,  mixed signal intensity Talar lesion seen with cortical breach,  MR demonstrable calcification, ossification with extensive soft tissue involvement  with unremarkable joints  and no encasing of  tendons or vessels

2) How do we sum it up?

Radiologically aggressive  osseous lesion .

In view of the  age, Primary malignant neoplastic etiology is possible. Calcium suggests  osteosarcoma  and tumor like lesion -aneurysmal bone cyst  are primarily differentials

3) Others?

Radiologically skeletal diagnosis contributes only 1/3 with clinical and Pathology other 2/3s

4) what are they ?

Aggressive infective etiology with chronicity including aggressive  variety of  Staphylococcal/Tuberculosis  etc

5) How do we proceed ?

To start with X- ray would   corroborate the  calcium/ossification. Bone scan of F18 (fluorine variety)  would give us the whole body CT with metabolite activity of the lesion

 Lungs on CT would be doubly beneficial to suggest or exclude  Infections, sequelae or metastatic foci

6) An USG/CT guided bx role???

Though highly tempting in view of approachable and apparently no risk, True cut biopsy  could lead to severe local bleeding and adequate  preparations  should readily address the issues

7) Any other Radiology role ?

Presurgical   embolization would be   complementary  in the management planning if necessary