Distal Sites of Innervation: Exam II

  1. True or False. Dorsal Ramus C2 is the origin of the greater occipital nerve.
    True. The dorsal ramus of C2 will refer to the greater occipital nerve. The greater occipital nerve was dissected out in dissection and serves to innervate the skin on the back of the head in its medial branches and the splenius capitus, longissimus capitus, and the semispinalis capitis muscles. All of which are attached to a cervical transverse process.
  2. The order of the names of the dorsal rami nerves going from C1 to C3 are what?
    Suboccipital nerve, Greater occipital nerve and 3rd occipital nerve.
  3. In dissection, we uncovered the rectus capitus posterior minor, rectus capitius posterior major, the inferior oblique and the superior oblique muscle on the back of the neck. What dorsal rami nerve are they innervated by and what level of dorsal rami do they originate from (i.e. C1, C2, C3)?
    The inferior oblique, superior oblique, rectus capitis posterior major, and rectus capitis posterior minor muscles are all innervated by the suboccipital nerve that originates from C1.
  4. Ventral Rami C1-C5 have several nerves that come off them. What are the two types of nerves that can originate? (i.e. what are their functions)
    They can either be cutaneous or mixed motor sensory branches.
  5. There are three mixed motor sensory branches (with post ganglionic sympathetic innervation) that originate from the C1 ventral rami. What are the names of the ones that innervate muscles?
    The two branches that come off the C1 ventral rami are the nerve to the geniohyoid and the nerve to the thyrohyoid branches. Both of which attach to the hyoid bone.
  6. If the superior root of ansa cervicalis originates from the C1 vertebrae, what roots does the inferior root of ansa cervicalis originate from?
    The inferior root of ansa cervicalis originates from the C2, and C3 vertebrae.
  7. The inferior and superior roots of ansa cervicalis innervate different muscles although they both arise from ventral rami. The superior root (C1) innervates one muscle while the inferior root (C2,C3) innervates three muscles. What are these muscles?
    The superior root of the ansa cervicalis innervates the superior oblique muscle while the inferior oblique (C2, C3) innervates the inferior oblique, the sternohyoid, and the sternothyroid muscles.
  8. Which of the roots of ansa cervicalis originates from the C2 vertebrae?
    The inferior root which innervates the sternothyroid muscle, the sternohyoid muscle, and the inferior oblique muscles of the neck.
  9. The cutaneous branches of the cervical plexus also arise from C1-C5 ventral rami. What is the name of the nerve that arises from the C2 vertebrae?
    The lesser occipital nerve is the cutaneous nerve branch that arises from C2. It serves to innervate the skin overlying the posterior lateral aspect of the head and neck.
  10. What are the names of the cutaneous nerve branches that arise from the ventral rami C2 and C3?
    The great auricular and the transverse cervical cutaneous nerve branches arise from the C2 and C3 ventral rami. They serve to innervate skin. The great auricular innervates the skin overlying the upper SCM, lower parotid region and the ear. Meanwhile the transverse cervical innervates the skin overlying the lower part of the SCM and the anterior neck.
  11. What is the name for the cutaneous nerve branches that arise from the C3 and V4 ventral rami? What do they innervate?
    The supraclavicular branches. The skin of the lower half of the posterior triangle of the neck.
  12. The dorsal rami from C4-C8 are divided into medial and lateral branches similar to C2 and C3. They each contain postganglionic sympathetic and sensory innervation. However, the lateral branch contains motor innervation. What is this innervation used for in the lateral branches? What do the medial branches innervate?
    The lateral branch of the C4-C8 dorsal rami contains motor innervation so it can innervate the overlying neck muscles of the cervical vertebrae. The medial branch of C4-C8 dorsal rami innervates the skin of the surrounding vertebrae.
  13. 3,4,5 keeps the diaphragm alive is in reference to what?
    The 3,4 and 5 of this saying refers to the number of ventral rami that supply the phrenic nerve which innervates the diaphragm.
Card Set
Distal Sites of Innervation: Exam II
Distal site of innervation for Anatomy Exam II