Lytic lesion with internal septations in the medullary cavity of the distal tibial diaphysis with slight medial eccentric location. Size is 18 x 19 x 36 mm (AP x transverse x craniocaudal). It is well-circumscribed, and is mildly expansile, associated with marked smooth cortical thickening with overlying smooth periosteal reaction over the medial tibial cortex.
The favored diagnosis is multifocal Brodie abscess secondary to chronic osteomyelitis. Less likely differentials include aneurysmal bone cyst or eosinophilic granuloma.
Further evaluation via contrast-enhanced MRI is recommended, as well as orthopedic opinion.