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': 'Open reduction is not required in which fracture : \nSelect and explain. \nA. Patella, B. Outer 1/3 of radius head, C. Condyle of humerus, D. Olecranon displaced #', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Involvement of > 1/3rd of the head is an indication for excision of the fragment (not open reduction).', 'role': 'assistant'}]