Open fractures are a common pathology seen in emergency departments, especially in trauma centers. In open fractures, the skin barrier has been compromised, exposing sterile bone to the environment. Considered a true orthopedic emergency, these fractures have high morbidity due to osteomyelitis, with infection rates up to 55%. (1) Appropriate and timely intervention in the emergency department with proper antibiotic therapy, wound care, and early orthopedic surgery involvement dramatically reduces the risk of developing osteomyelitis. In this post we will discuss antibiotic recommendations for osteomyelitis prophylaxis for open fractures. Initial management of open fractures is discussed in another post.