Common urgent musculoskeletal injuries in primary care.

The patient who presents with an acute painful synovitis of a single joint provides a significant diagnostic and therapeutic challenge to the primary care physician. An aggressive approach is required to differentiate a potential infectious arthritis, with its attendant morbidity and potential mortality, from other causes of monarthritis that are not immediately life-threatening. This article reviews the common causes of acute monarthritis in the adult, including the presentation, as well as guidelines for rapid and efficient diagnosis and management. Common causes include infections (bacterial/Lyme/mycobacterial/viral), microcrystalline disease (gout/pseudogout), and traumatic and reactive arthropathy. In addition, guidelines are suggested for the management approach to acute monarthritis when initial diagnostic testing is unrevealing of a specific diagnosis.