Review Question - QID 215020

A 65-year-old man presents to the emergency department after a ground-level fall. His wife states that he has been complaining of low back pain radiating down the back of his leg since yesterday. He has had no prior falls. His past medical history includes prostate cancer status post radical prostatectomy. He does not take any medications. He has never smoked and denies any intravenous drug use. The patient’s temperature is 99.4°F (37.4°C), blood pressure is 132/78 mmHg, pulse is 92/min, and respirations are 18/min. On physical exam, the patient has diminished sensation in his feet, 2/5 strength to ankle dorsiflexion bilaterally, and hyporeflexia in the lower extremities. A bladder scan shows a post-void residual volume of 300 mL. Which of the following is the most appropriate next step in management?