A 62-year-old man presents with an acutely swollen, hot and very painful right knee. He is febrile at 38.9°C and feels unwell. There is marked restriction of movement. What is the most appropriate immediate management?AStart oral NSAIDs and review in 48 hoursBArrange urgent joint aspiration for Gram stain, culture and crystal analysis and start empirical intravenous antibioticsCOrder a plain X-ray and arrange routine orthopaedic clinic reviewDInject intra-articular steroid in the emergency departmentEAdvise rest, ice and elevation onlyCheck my answer