USP6 and aneurysmal bone cyst: Similarly, giant cell lesions of the small tubular bones are now considered “solid” aneurysmal bone cysts (ABC) since the majority show rearrangements of USP6 which can be identified in an almost uniformly benign group of formerly thought to be unrelated lesions (ABC, myositis ossificans, nodular fasciitis, cranial fasciitis, fibroma of tendon sheath, and fibro-osseous pseudotumor of the digits, Fig. 2).