Monoarticular arthritis update: Current evidence for diagnosis and treatment in the emergency department.

Monoarticular arthritis presentations in the emergency department are increasing as the population ages and gets heavier. Many etiologies--from trauma to infection to autoimmune-mediated inflammation--are associated with significant disability or early mortality, and their treatments are associated with adverse effects. A systematic approach to evaluating patients with monoarticular arthritic complaints is important for relieving pain, diagnosing systemic illness, and unmasking true arthritis emergencies. Septic arthritis is a rapidly destructive process that can cause significant disability in a matter of hours or days, with relatively high mortality. Other causes of monoarticular arthritis may cause disability in the long term. In all cases, accurate diagnosis and appropriate therapies are crucial for resuming activities and preventing long-term deficits. This review examines the diagnosis and treatment of monoarticular arthritis, with a focus on recent evidence in the diagnosis of septic arthritis and new research on gout therapies. Modalities for pain control and new techniques for imaging are discussed.