A 42-year-old male reports pain in his lower back for the past month. The pain sometimes radiates to his left leg. In determining the cause of the back pain, based on your knowledge of anatomy, what nerve roots might be involved? How would you test for each of them? What other symptoms need to be explored? What are your differential diagnoses for acute low back pain? Consider the possible origins using the Agency for Healthcare Research and Quality (AHRQ) guidelines as a framework. What physical examination will you perform? What special maneuvers will you perform?