This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
[{'content': "Not True about perthe's disease \nSelect and explain. \nA. Femoral valgus derotation osteotomy, B. Chiari osteotomy, C. Coxa plana, D. More common in females", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]