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: Surgery
[{'content': 'Crutch palsy is injury to which nerve? \nSelect and explain. \nA. Radial nerve, B. Ulnar nerve, C. Median nerve, D. Musculocutaneous nerve', 'role': 'user'}, {'content': "Answer: A \nExplanation: Answer-A. Radial nerveVery high lesions of radial nerve may be caused by trauma or operations around the shoulder.This is seen in drink and drug addicts who fall into a stupor with the arm dangling over the back of a chair ('saturday night pals/) or in thin elderly patients using crutches ('crutch palsy').", 'role': 'assistant'}]