Intermediate Accessory Nerve Quiz

Q1. How do spinal accessory nerve fibers reach the skull before exiting through the jugular foramen?

• They travel through the internal acoustic meatus
• They enter through the carotid canal and leave through foramen ovale
• They ascend through the foramen magnum before exiting through the jugular foramen
• They pass directly through the hypoglossal canal from the spinal cord

Q2. Which cranial nerves accompany CN XI through the jugular foramen?

• Glossopharyngeal and vagus nerves
• Trigeminal and facial nerves
• Oculomotor and trochlear nerves
• Optic and abducens nerves

Q3. After leaving the jugular foramen, which muscle does the accessory nerve usually encounter first?

• Masseter
• Mylohyoid
• Sternocleidomastoid
• Buccinator

Q4. After supplying sternocleidomastoid, where does CN XI become especially superficial and vulnerable?

• Posterior triangle of the neck
• Pterygopalatine fossa
• Carotid canal
• Submandibular triangle only

Q5. Which muscle does CN XI enter after crossing the posterior triangle?

• Geniohyoid
• Platysma
• Anterior scalene
• Trapezius

Q6. What is the relationship between CN XI and the cervical plexus in the innervation of sternocleidomastoid and trapezius?

• CN XI provides principal motor fibers while cervical nerves contribute proprioceptive fibers
• The cervical plexus provides all motor fibers and CN XI is purely sensory
• CN XI and the cervical plexus innervate only the skin over these muscles
• There is no anatomical relationship between them

Q7. Which cervical spinal nerve levels commonly contribute proprioceptive fibers to sternocleidomastoid?

• C7 and C8
• C2 and C3
• C5 and C6 only
• T1 and T2

Q8. Which cervical spinal nerve levels commonly contribute fibers associated with trapezius?

• C6 and C7
• C3 and C4
• T2 and T3
• C1 only

Q9. What scapular abnormality may follow significant trapezius weakness from CN XI injury?

• Shoulder droop with abnormal scapular position
• Fixed medial deviation of the eye
• Mandibular protrusion
• Loss of tongue sensation

Q10. Why is CN XI at risk during procedures in the posterior triangle of the neck?

• It lies within the vertebral canal throughout the neck
• It runs inside the internal carotid artery
• It is enclosed within the parotid duct
• It has a superficial course across the posterior triangle