SPINAL CORD FUNCTIONING AT C5

 

What Motor Function is Consistent with C5?    
  • The nerve root of C5 runs between vertebrae C4 and C5. 
  • Motor function includes:
    • movement of the deltoid (abduction of arm - movement of the arm at shoulder away from midline)
    • weak bicep muscles (able to flex forearm at elbow) 
    • lattissmus and pectoralis function is not present at C5 
What Sensory Function is Consistent with C5?    
  • C5 sensation includes bicep area (C4 provides sensation to shoulder)
Assessment of C5 Motor Function    
Assess and document motor function using motor scale from 0-5


Bicep:

  • have patient flex or bend elbow 
  • evaluate the ability to bend the elbow while examiner holds forearm to create resistance
  • C5 DOES NOT allow straightening of the elbow
Deltoid:
  • evaluate ability to abduct shoulder (move arm away from body)
  • C5 DOES NOT provide adduction of shoulder (movement towards body)
  • Latissmus and pectoralis function is not present at C5
   
Assessment of C5 Sensory Function    
  • Test bicep on one side for sensation, then test same spot on opposite side
  • Always apply the same amount of pressure to each side
  • Ask patient to compare sensation on side A to side B
  • Conceal test from the patient

Light touch:

  • use wisp of cotton or tissue; touch bicep on either side and assess sensation

Sharp or temperature touch:

  • use safety pin or blunt end needle
  • pain is a better assessment than temperature for this pathway because patients need to be able to articulate that they can distinguish hot or cold; this is unreliable among intubated patients
  • assess bicep sensation on either side
   
Expected Outcome    
  • ability to feed self with assisted devices (C5 does not provide any hand movements)
  • ability to operate modified wheel chairs for short distances 
   

 

References:

 

Barr, M, and Kiernan, J. (1993). The Human Nervous System: An Anatomical Viewpoint. Philadelphia: Lippincott. pp 84-85.

Keppler, J. (1987). Acute spinal cord injury. Critical Care Clinics. July. 3:3. pp. 638-641.

Netter, F. (1989). Atlas of Human Anatomy. New Jersey: Novartis.

Waxman, S. (1996). Correlative Neuroanatomy. 23rd Ed.  Stamford: Lange. pp 46-52, 352-355, 370.
 


Brenda Morgan
Clinical Nurse Specialist, CCTC
May 11, 2001. Updated: January 15, 2019