Basal Skull Fracture Diagnosis

The patient presents with specific signs following a head injury sustained in a road traffic accident:

• Consciousness: GCS 14/15 (indicating mild impairment).
• Ear Bleeding: Suggests possible temporal bone involvement or middle ear trauma.
• Nasal CSF Leak (Rhinorrhoea): Indicates a potential breach in the skull base, allowing cerebrospinal fluid to escape.
• Bruising behind the ear (Battle's sign): A classic sign associated with fractures of the posterior cranial fossa, often involving the mastoid bone, which is part of the skull base.

This combination of signs, particularly the CSF leak from the nose and Battle's sign, strongly points towards a Fracture of the base of skull.

Clinical Diagnosis Reasoning

Let's analyze the options:

• Extradural haematoma: While a possible complication of head injury, it typically involves arterial bleeding and may present with a lucid interval. It doesn't specifically explain the CSF leak or Battle's sign as primary features.
• Fracture of the base of skull: This diagnosis directly correlates with the observed signs: bleeding from the ear, CSF rhinorrhoea, and Battle's sign are hallmark indicators of a break in the skull's base.
• Cerebral concussion: This is a functional brain injury, characterized by temporary neurological disturbance. It doesn't inherently cause visible signs like CSF leaks or specific bruising patterns like Battle's sign.
• Traumatic subarachnoid haemorrhage: This involves bleeding into the subarachnoid space. While it can occur with head trauma, the specific signs presented (ear bleeding, nasal CSF leak, Battle's sign) are more indicative of a structural fracture than just bleeding into the meninges.

Therefore, the most probable clinical diagnosis based on the clinical presentation is a fracture of the base of the skull.