Clear rhinorrhea can indicate which of the following injuries?

Clear rhinorrhea, which is the discharge of clear fluid from the nose, is most commonly associated with a basilar skull fracture. This type of fracture often occurs at the base of the skull and can lead to the leakage of cerebrospinal fluid (CSF) through the nasal passages. The presence of clear fluid suggests that the fluid is likely CSF rather than other types of fluids or discharge.

When a basilar skull fracture occurs, it can compromise the protective barriers that normally keep CSF contained, allowing it to exit through any associated injuries or tears in the meninges. Clear rhinorrhea is a clinical sign that can be particularly telling, as it indicates a potential breach in the protective layers of the brain.

In contrast, frontal skull fractures, concussions, and contusions may present with other symptoms but are less likely to cause clear rhinorrhea as a symptom directly associated with the injury itself. For instance, while a frontal skull fracture may cause nasal symptoms, it typically does not lead to clear rhinorrhea that specifically indicates CSF leakage. Concussions and contusions are primarily considered types of brain injuries that do not necessarily involve clear nasal discharge, making them less relevant in this context.