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: Unknown
[{'content': 'The operative procedure is known as "microfracture" is done for the \nSelect and explain. \nA. Delayed union of femur., B. Non union of tibia, C. Loose bodies of ankle joint, D. Osteochondral defect of femur', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e. Osteochondral defect of the femurRef. Various internet sites (www.orthopedics.hss.edu, www.kneeguru.co.uk)Microfracture is an arthroscopic procedure used to treat osteochondral defects (damaged areas of articular cartilage of the knee)", 'role': 'assistant'}]