L2.2 Cervical Spine & Neck

Question 1

What are the cervical landmarks?

Answer 1

• C1 – level with hard palate
• C1/2 – open mouth
• C2/3 – Mandible
• C3 – Hyoid Bone
• C4 – Upper border of thyroid cartilage
• C6 – Cricoid cartilage

Question 2

What are the characteristics of a typical vertebrae?

Answer 2

• Bifid spinous process (splits at the end →↑SA → muscles & lig attachment)
• Has a transverse foramen (where vertebral A passes through up to the brain)
• Uncinate process (bony projection)

Question 3

What are the atypical vertebrae?

Answer 3

• C7 – longest spinous process (not bifid)
  
  • AKA: vertebra prominens
• C1 – Atlas (just ring, no body – body migrated during embryological development → attaches to body of C2 → becomes the dens → allows rotation of skull)
  
  • Long transverse process
  • Facet for dens
• C2 – Axis
  
  • Has dens (odontoid process)

Question 4

Characteristics of a cervical facet joint?

Answer 4

• Horizontal one side (weight bearing), oblique the other (prevents sliding)
  
  • ∴more susceptible to injury, esp. hyperextension
• 3 joints: for rotation (50% rotation of cervical spine)

Question 5

Ligaments which hold the atlanto-axial joint in place?

Answer 5

• Atlanto-axial joint held in plane by longitudinal ligament
• Dens protected well protected by bones in front
• But Back not protected – Could tilt backwards
• Transverse ligament: prevents it from tilting back into space
• Alar ligament: limiting rotation
• Susceptible to injury when head is flexed and rotated + muscles relaxed

Question 6

What are the 2 compartments of fascia of the neck?

Answer 6

• Superior
• Deep:
  
  • 1) Investing layer
  • 2) Pretracheal
  • 3) Prevertebral
  • 4) Carotid sheath

Question 7

Sternocleidomastoid

Answer 7

• Origin: 2 heads to manubrium & med 1/3 of clavicle; Insertion: Mastoid process of the temporal bone
• Separate ant/pos triangles
• Within 2 folds of investing fascia
• Action: Bilaterally: flex neck; unilaterally: lat flex & rotation to opposite side
• Innervated by 11th cranial nerve

Question 8

ANT strap muscles

Answer 8

• Suprahyoid & infrahyoid muscles
• Deep to investing fascia
• Action: steady/move the hyoid bone & larynx
• Susceptible to injury in neck compression

Question 9

Scalene muscles (lat vertebral muscles)

Answer 9

• Origin: Transverse processes; Attaches to: 1st and 2nd ribs
• Laterally flex neck
• Accessory muscles to respiration
• Brachial plexus & subclavian artery passes between ANT and mid scalene muscles
  
  • Site for anaesthesia
• Phrenic N lies ANT to scalene muscles

Question 10

Postvertebral muscles

Answer 10

• Oppose weight of head which acts in front of the occipital condyles
• Extends head, neck, and cervical spine

Question 11

Where does the cervical nerve pass through and what is the clinical significance?

Answer 11

• C1 & 2 nerve passes behind facet joints
  
  • Potential of osteophytes compression

Question 12

What is the course of the vertebral artery and what are it’s landmarks?

Answer 12

• Vertebral artery course: through the transverse foramina (C6-1)
• Important landmarks:
  • Ant tubercle C6 (carotid tubercle)
  • C4 vertebra (bifurcation CCA)