Course and Branches of Cranial Nerves IX, X, XI, and XII in the Neck

Introduction

The cranial nerves IX, X, XI, and XII play critical roles in motor and sensory functions of the head and neck.

Cranial Nerve IX (Glossopharyngeal Nerve)

Course

The glossopharyngeal nerve originates from the medulla oblongata and exits the skull through the jugular foramen.

Branches and Functions

• Pharyngeal branches - contribute to pharyngeal plexus
• Carotid sinus branch - regulates blood pressure

Cranial Nerve X (Vagus Nerve)

Course

The vagus nerve originates from the medulla and exits through the jugular foramen, extending into the thorax.

Branches and Functions

• Superior laryngeal nerve - controls laryngeal muscles
• Cardiac branches - regulate heart rate

Cranial Nerve XI (Accessory Nerve)

Course

The accessory nerve arises from the spinal cord and medulla and exits via the jugular foramen.

Branches and Functions

• Spinal root - innervates sternocleidomastoid and trapezius muscles

Cranial Nerve XII (Hypoglossal Nerve)

Course

The hypoglossal nerve arises from the medulla and exits through the hypoglossal canal.

Branches and Functions

• Muscular branches - innervate tongue muscles