This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Musculoskeletal Radiology, Subject name: Radiology
[{'content': 'A 48 year old man known to you with a long history of low back pain, presents once again with similar symptoms. He has had a previous X - ray showing degenerative disc changes 6 years earlier. What is to be done next? \nSelect and explain. \nA. Repeat X-ray should be done, B. X-Ray should not be repeated, C. If any systemic disease suspected, MRI should be done, D. If suspected neurological deficit CT should be done', 'role': 'user'}, {'content': "Answer: B \nExplanation: In the absence of any 'red flag' signs, there is no indication for fuher X - rays. Red flag signs: Thoracic pain Fever Weight loss Bladder or bowel dysfunction Carcinoma history Neurological deficit Onset < 20 years or > 55 years. For neurological symptoms, MRIa best to examine just the spine. If systemic disease was suspected, CT would be best", 'role': 'assistant'}]