Foramina and Passing Structures

FORAMINA AND PASSING STRUCTURES QUICK NOTES 

📌 WHAT ARE FORAMINA?

🔹 Foramina are openings or holes in bones through which structures (nerves, blood vessels) pass.

🔹 These structures are essential for connecting different body regions, ensuring that nerve impulses and blood flow reach the necessary areas.

📌 MAJOR FORAMINA & THEIR PASSING STRUCTURES

A. Skull Foramina

1. Foramen Magnum

   • Location: Occipital bone.

   • Passes: Spinal cord, vertebral arteries, accessory nerve (CN XI), and the meninges.

2. Optic Canal

   • Location: Sphenoid bone.

   • Passes: Optic nerve (CN II) and ophthalmic artery.

3. Superior Orbital Fissure

   • Location: Sphenoid bone.

   • Passes: Oculomotor nerve (CN III), Trochlear nerve (CN IV), Abducens nerve (CN VI), and the ophthalmic branch of the trigeminal nerve (CN V1).

4. Foramen Ovale

   • Location: Sphenoid bone.

   • Passes: Mandibular nerve (V3) and accessory meningeal artery.

5. Foramen Rotundum

   • Location: Sphenoid bone.

   • Passes: Maxillary nerve (V2).

6. Foramen Spinosum

   • Location: Sphenoid bone.

   • Passes: Middle meningeal artery and vein.

7. Internal Acoustic Meatus

   • Location: Temporal bone.

   • Passes: Facial nerve (CN VII), Vestibulocochlear nerve (CN VIII), and labyrinthine artery.

8. Jugular Foramen

   • Location: Between temporal and occipital bones.

   • Passes: Internal jugular vein, Glossopharyngeal nerve (CN IX), Vagus nerve (CN X), Accessory nerve (CN XI).

9. Hypoglossal Canal

   • Location: Occipital bone.

   • Passes: Hypoglossal nerve (CN XII).