Which of the following is a warning sign of a fracture?

Significant pain and swelling are key indicators of a fracture. When a bone breaks or cracks, it often leads to inflammation in the surrounding tissues, resulting in swelling. The body responds to the injury with pain as a signaling mechanism to protect the area from further harm. This intense pain and the resulting swelling can help identify the presence of a fracture and indicate the need for immediate evaluation and care.

Increased mobility in the limb suggests that there may not be a significant injury, as fractures typically cause restricted movement. Loss of pain sensation is unusual in fractures; pain is generally a prominent symptom. Decreased blood flow could occur with certain fractures but is not a primary warning sign for fractures themselves, as it can vary depending on the type and location of the fracture.