The pterion is the H-shaped suture junction on the lateral skull where four bones meet. It overlies which important structure, and why is a fracture here clinically significant?

• A Middle cerebral artery (M1 segment); rupture causes massive ischemic stroke
• B Anterior branch of the middle meningeal artery; fracture causes extradural (epidural) hematoma ✓
• C Posterior branch of the middle meningeal artery; fracture causes posterior fossa hematoma
• D Superior sagittal sinus; fracture causes subdural hematoma

Explanation

The pterion is the junction of the frontal, parietal, temporal, and greater wing of sphenoid bones. It is the thinnest region of the lateral skull and overlies the anterior branch of the middle meningeal artery (running in the epidural space in a groove of the temporal bone). A blow to this area (e.g., in assault or sports) can fracture the thin bone and tear the artery, causing an extradural (epidural) hematoma — typically with a lucid interval followed by progressive neurological deterioration due to temporal lobe compression.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.