Question 10
A 76-year-old woman presents with 3 days of fever and 1 day of severe pain in her left knee to the point where she can no longer stand. She has no past medical history. She is not sexually active. On examination, her temperature is 102°F. Her heart rate is 100 beats/min, with blood pressure of 108/65. Her left knee is tender, with erythema and a palpable effusion. Her cardiac, lung, and abdominal examinations are all normal. Which of the following should you do?