Aneurysmal bone cyst of the 4th metacarpal bone

An expansile lytic lesion with multiple bony septa is noted involving almost the entire 4th metacarpal bone of the left hand. Significant cortical expansion and thinning with no definite pathological fracture.

An expansile lytic lesion of the left 4th metacarpal with intermediate to slightly hyperintense T1 and hyperintense T2 and STIR signal with characteristic multiple fluid/fluid levels and multiple bony septa. the bony septae shows hypointense T1 and T2 signal intensity. Small foci of T1 hyperintensity are noted likely related to subacute blood. The lesion shows rather heterogeneous intense enhancement with enhancing bony septae. Significant cortical expansion and thinning with possible cortical breaching suggesting pathological fractures on MRI with minimal extra-osseous soft tissue component.