Presentation
Pain in the ankle of insidious onset without swelling or limitation of movement .
Patient Data
The MRI images demonstrate an expansile multiloculated lesion in the distal metaphysis of the tibia causing endosteal scalloping without cortical disruption and showed multiple cystic spaces with fluid -fluid level of variable signal intensity that appear T1 hyperintense presumably representing blood of variable age. The lesion abuts the physis and demonstrates sharp transition zone.
This lesion is radiologically consistent with aneurysmal bone cyst .
Case Discussion
Aneurysmal bone cyst ( ABC) is an expansile osteolytic lesion with a thin wall, containing blood filled cystic cavities, usually occurs in children and adolescent. Multiple theories are proposed to explain the etiology of the cyst which includes reaction to other existing bone lesion, trauma and vascular bone malformation.