A nurse on an orthopedic floor is completing the morning assessments on several clients. Which of the following clients has the greatest risk for fat embolism syndrome (FES)

A. A 24-year-old male who has a casted femur fracture: Long bone fractures, particularly of the femur, are the most common cause of fat embolism syndrome (FES). Fat globules can enter the bloodstream from the bone marrow, leading to respiratory, neurologic, and dermatologic manifestations. Young adults are at higher risk due to the frequency of high-energy trauma. B. A 10-year-old female who has an ulnar fracture in an external fixator: FES is rare in small bone fractures such as the ulna, especially in children. The risk is minimal because less marrow fat is released into circulation compared with long bones like the femur. C. A 45-year-old male who has multiple rib fractures: Rib fractures carry a low risk for FES because they involve flat bones with less marrow fat. The primary complications are respiratory in nature, such as pneumothorax or pulmonary contusion. D. A 62-year-old female who has vertebral fractures due to osteoporosis: Vertebral fractures in older adults rarely result in FES because the marrow fat released is minimal, and low-energy trauma is usually involved. Other complications, such as spinal cord injury or chronic pain, are more likely.