×
MedSchool: Ace Your OSCEsThe Medical Company
 
 
 
 
 
GET - On the App Store
View
Cranial Nerves
 
 

Accessory Nerve Exam

February 15th, 2021
 
 
 
Bookmark

Accessory Nerve Muscular Weakness

  • How to Elicit

  • Sternocleidomastoid - ask the patient to turn their head against resistance.A CN XI lesion may cause weakness on head turning away from side of lesion
  • Trapezius - ask the patient to shrug their shoulders against resistance.An CN XI lesion may cause weakness in shoulder elevation on ipsilateral side
  • Causes of Accessory Nerve Muscular Weakness

  • Upper motor neuron  brainstem or cervical spinal cord
  • Lower motor neuron - accessory (XI) weakness
  • Interpretation

  • Isolated Trapezius WeaknessVentral brainstem, lower cervical spinal cord or lower accessory nerve lesion
  • Isolated Sternocleidomastoid WeaknessBrainstem or upper cervical lesion
  • Weakness of Trapezius and Contralateral SternocleidomastoidUpper motor neurone lesion on the side of the SCM weakness, above the accessory nucleus
  • Weakness of Ipsilateral TrapeziusContralateral brainstem, ipsilateral high cervical cord, or accessory nerve lesion
Next Page
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge
Sign Up Now
   
 
 

Snapshot: Initialising...