Arthritis in the intensive care unit.

Acute arthritis in critically ill patients may be caused by local or systemic infection, by a flare of chronic joint disease such as rheumatoid or crystal-associated arthritis, or by less common entities such as hemarthrosis. Diagnosis requires analysis of synovial fluid, and appropriate treatment is based on its findings. Prompt diagnosis and treatment are usually necessary to prevent the significant morbidity associated with these conditions.