A 54-year-old woman presents with a painful, swollen right knee that became symptomatic over 12 hours. She has a temperature of 37.8°C and is unable to fully flex the knee. There is no history of trauma, and the knee is warm with a moderate effusion. Which investigation is the most appropriate next step?
More from AMC
See allA 17-year-old girl presents six hours after a deliberate ingestion of tablets taken from the family bathroom cabinet. She complains of nausea, repeated vomiting…
A 28-year-old woman is brought in by ambulance 90 minutes after being found drowsy next to an empty box of amitriptyline. Her Glasgow Coma Scale score is 12, he…
A 21-year-old man collapses at the 14 km mark of a city fun run on a 34°C day. In the trackside medical tent he is confused and agitated with a Glasgow Coma Sca…
A 26-year-old backpacker is snorkelling off Port Douglas in far north Queensland in December when she feels a mild sting on her forearm, leaving only faint redn…
A 34-year-old man in suburban Sydney felt a sharp pinprick on the back of his hand while moving pot plants stacked against the house. Over the next two hours he…