Knee Pain

Emergency department management of knee pain requires a systematic approach to differentiate between traumatic injuries, osteoarthritis, and septic arthritis. Osteoarthritis remains the most common etiology for atraumatic knee pain, with management centered on weight loss, exercise, and NSAIDs. The Ottawa Knee Rule effectively guides imaging decisions, while ultrasound provides superior sensitivity for detecting joint effusions and guiding arthrocentesis, significantly improving diagnostic accuracy over landmark-based techniques. Septic arthritis, most commonly caused by *Staphylococcus aureus*, necessitates urgent joint fluid analysis, where lactate levels and white blood cell counts serve as critical diagnostic indicators. While knee immobilizers and corticosteroid injections offer symptomatic relief, they require careful patient selection to avoid complications like cartilage degeneration or interference with future surgical interventions. Integrating physical therapy early in the emergency setting enhances patient outcomes and facilitates better long-term management for those lacking immediate orthopedic follow-up.