This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bony dysplasia and soft tissue affection, Subject name: Orthopaedics
[{'content': 'What is Felon - \nSelect and explain. \nA. Infection of nail fold, B. Infection of ulnar bursa, C. Infection of pulp space, D. Infection of DIP joint', 'role': 'user'}, {'content': 'Answer: C \nExplanation: PULP INFECTION (FELON) The distal finger pad is essentially a closed fascial compament filled with compact fat and subdivided by radiating fibrous septa. A rise in pressure within the pulp space causes intense pain and, if unrelieved, may threaten the terminal branches of the digital aery which supply most of the terminal phalanx. Pulp-space infection is usually caused by a prick injury; blackthorn injuries are paicularly likely to become infected. The most common organism is Staphylococcus aureus. The patient complains of throbbing pain in the finger-tip, which becomes tensely swollen, red and acutely tender. Reference- Apley&;s system of ohopaedics 9th edn -pg 432', 'role': 'assistant'}]