MEDIVEERSETHE PRACTICAL HUB
Identify its root on the inferior brain reference, then trace its extracranial course using the relationship map. Distinguish sensory, motor and autonomic components. Confirm its skull-base exit or spinal origin.
Zoom in, then drag to inspect. Keyboard: + / − to zoom, arrows to pan, 0 to reset. Tap the numbered markers to explore parts.
Accessory nerve (XI): magnified reference view with a numbered learning marker. The complete original plate is available in the next view.
Image: OpenStax College / university open textbook · Source / original · CC BY 4.0Numbered markers and focused views are Mediveerse learning overlays; the original reference is linked above.
Accessory nerve (XI)
Understand what you see.
Spinal accessory fibres supply sternocleidomastoid and trapezius.
Zoom into the original labels. Practise pointing out each structure, then explain it aloud. Diagrams are teaching references; specimen appearance and slide staining vary.
How to recognise it.
- Identify its root on the inferior brain reference, then trace its extracranial course using the relationship map
- Distinguish sensory, motor and autonomic components
- Confirm its skull-base exit or spinal origin
Point them out.
Tap a number to open its reference, zoom in and locate the structure. Numbers stay the same across views. This key follows landmarks visible in the reference images.
Think first. Then reveal.
Say your answer aloud before opening the suggested response.
Examiner-style prompts: identify the structure, explain its relations, then answer the applied follow-up. These are revision questions, not authenticated past papers.
01Identify accessory nerve (xi) and give its main role.+
Identify by its course and target. Distinguish sensory, motor and autonomic components. Confirm its skull-base exit or spinal origin. Spinal accessory fibres supply sternocleidomastoid and trapezius.
02Why is it vulnerable in the posterior triangle?+
It crosses relatively superficially between SCM and trapezius.
03What follows injury?+
Weak shoulder elevation and impaired scapular rotation from trapezius weakness; SCM deficits depend on lesion level.
04Point out three important relations and explain their significance.+
Spinal rootlets; Foramen magnum and jugular foramen; SCM and trapezius. Spinal accessory fibres supply sternocleidomastoid and trapezius. Use the reference plate to locate the region; the relationship map organises the associations and is not drawn to scale.
Read the references.
Credited anatomical plates, microscopy and university teaching references. Individual image credits appear below the viewer. Historical plates can use older terminology; use the lesson text for current names.