[Internal differential diagnoses in acute back pain : An internal perspective on the possible causes of acute back pain].

The majority of patients with acute back pain have no serious underlying disease; however, many internal diseases can be manifested as acute or chronic back pain. Therefore, in the assessment of patients with back pain the clinical history and clinical examination are important in order to detect indications for a possible underlying disease. Particularly red flags that indicate an acute or life-threatening disease should not be missed. In most cases where such red flags, risk factors or clinical indications are not present, no systematic search for internal underlying diseases is necessary. This article summarizes the most relevant differential diagnoses and clinical indications as well as warning symptoms.