Review Question - QID 214051

You are asked to evaluate a 17-year-old female with complaints of low back pain for the last 2 months. The patient was previously admitted for pyelonephritis and treated with IV antibiotics. She has a low-grade fever and is hemodynamically normal. On examination she has paraspinal tenderness and spasm at the lumbar levels. She does not have any extremity pain or neurological symptoms. Her neurological examination is unremarkable. However, you do notice that she has worsening of pain with sitting or standing but the pain improves when she lies flat. Her CRP and ESR are both elevated. Her radiographs of the lumbar spine show paraspinous soft tissue swelling and disk space narrowing of the L3/4 disc space. Of the options listed, what is the best next step?