Weekly Radiology Rounds: December 15, 2008

1. History: 4 year old female presents to ED with pain and limited range of motion to left knee

2. (history continued) Patient has approximately 1 year history of left knee pain and swelling. Recently treated with naproxen only.

3. What do you see? Lytic lesion with sclerotic boarders abutting the physis What is your differential diagnosis? Location…location…location

4. Benign or malignant? Well defined, sclerotic boarders, relatively narrow zone of transition… LIKELY BENIGN

5. T1 T2 T1 with Gad Decreased signal Fluid signal centrally Enhancing rim Large soft tissue collection Appearance consistent with abscess Where did it start? Bone or soft tissue? Usually hematogenous to bone with soft tissue extension

6. Extensive symptoms for a year T2

7. Intraoperative Curettage

8. Diagnosis Brodie’s Abscess