This case shows the typical radiographic appearance of aneurysmal bone cyst. While the appearance on MRI T2 weighted image is consistent with aneurysmal bone cyst, the presence of an enhancing soft tissue component suggests a coexisting lesion. One third of aneurysmal bone cysts are actually secondary to bone lesion like giant cell tumor or chondroblastoma.  The patient underwent curettage/debulking of lesion and bone grafting was done. The histopathology result: 

"LEFT METACARPAL:

CONSISTENT WITH GIANT CELL TUMOR WITH SECONDARY ANEURYSMAL BONE CYST."

The patient was followed up for long period with no evidence of recurrence.