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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Secondary aneurysmal bone cyst arises in -
assistant
The correct answer is  Most of the time (80%) aneurysmal bone cyst is primary, and no other pathology is found.
Secondary aneurysmal bone cysts (20%) occurs when bone changes of aneurysmal bone cyst occur in a pre-existing lesion:-


Giant cell tumors (osteoclastoma) : - Most common      
Osteoblastoma 
Simple bone cyst
Non-ossifying fibroma  
Telangiectatic osteosarcoma
Metastasis
Fibrous dysplasia
Paget's disease
 Chondromyxoid fibroma
Chondroblastoma