Back pain
Low-back pain (LBP) is a common presenting complaint to the primary care physician and in the emergency department. In the majority of cases, symptoms arise from benign conditions that do not merit emergent imaging studies. There are several causes, however, which may lead to disability or death if not promptly identified and treated including epidural abscess, discitis/osteomyelitis, unstable spinal fracture, cord-compressive metastasis, and expanding/leaking abdominal aortic aneurysm (AAA). It is important for physicians to maintain a high index of suspicion for these potentially devastating pathologies and to be able to discern these from more benign causes of back pain. It is also important that primary care and emergency department physicians do not over-utilize diagnostic imaging in patients without appropriate clinical indications, as this leads to increased costs, unnecessary radiation exposure, and can potentially result in unnecessary interventions or undue psychological distress. Satisfying these obligations requires a systematic approach that relies on historical and clinical features to guide appropriate use of imaging resources. In this chapter, we will outline a clinical paradigm approach to the patient who presents with acute LBP. This will include identifying relevant factors in the clinical history, examination, and laboratory features that are important in the diagnosis of a patient with acute LBP all of which enable the physician to establish an initial differential diagnosis. We will also review an approach to imaging in these patients and emphasize how individual imaging tests can help to refine the diagnosis, and result in a specific diagnosis, in most patients.