This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Orthopaedics
[{'content': 'All are true about aneurysmal bone cyst except - \nSelect and explain. \nA. Eccentric, B. Expansile & lytic, C. Treated by simple curettage, D. Metaphysis of long bones', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Aneurysmal bone : Etiology and pathogenesis: 1 Traumatic event result in an area of haemorrhage that maintain connection with the original with the disrupted feeding vessels. Subsequently giant cell granuloma-like can develop after loss of connection with the original vascular source 2. Frequently develops secondary within another lesion of bone as a result of disrupted vascular dynamics in pre-existing intrabony lesion ex. Central giant cell tumors Age : Young adults < 30 Years Location: Shaft of long bones Veebral column 2% Jaw bone; posterior mandibular is more common Sex : No predilection Manifestations: Rapidly growing swelling Painful frequently with parathesia ref : maheswari 9th ed', 'role': 'assistant'}]