1. General Anatomy
SHB

2. OBJECTIVES:
1. Be able to identify within the cross section of a spinal cord: cervical/thoracic/lumbar level,
dorsal horn, ventral horn, intermediate gray, intermediolateral cell column, substantia gelatinosa; nucleus proprius; nucleus dorsalis; dorsal columns
2. . Be able to describe: the function: spinal nerve, dermatome, sympathetic chain, cauda equine, conus medullaris, and dentate ligament.

3. Spinal Cord Anatomy Gross Anatomy Dermatomes Functional Components
General Internal Features

4. Spinal nerves come out above the same named vertebrae, until nerve c8, which comes out of the cord below vertebra C7. The rest of the nerves come out below their corresponding vertebrae.—Thus vertebra C7 has 2 nerves associated with it-----c7 and c8

5. Care must be taken during spinal tap

7. Note denticulate ligaments

8. Fryzstak does not like mooses—but they like him!

9. ramus
For the most part sympathetic s have short preganglionis and long postganglionics—exception: splanchnics, the greater splanchnic (t5-9) synapses in the celiac ganglion, the lesser (t10-11) in the superior mesenteric and aortico renal ganglia, and the least (t12) in the renal plexus.

10. Pretty sympathetic chain and splanchnics

13. One anterior –two posterior
All spinal arteries come from the vertebrals
One anterior –two posterior

14. sca
The vertebrals contribute to the Circle of Willis
aica
pica

15. This is where the circle lives.

16. Somites
Dermis
Muscle
Skeleton
Icky—poo,------embryo stuff

17. Dermatomes vs Peripheral Nerve Fields
Review the diff between dermatomes and peripheral cutaneous nerves

18. Individual dorsal roots

19. ---forming a “band-like” sensory pattern.

20. While some dorsal roots send out fibers that unite and form peripheral nerves that use or overlap 2 or more dermatomes.

22. C6
These are the key ones.

26. Where the dorsal root enters.

27. Separation between gracilus and cuneatus—several slides ahead

28. Where the anterior spinal artery lives.

29. Here is where the ventral root leaves.

30. White matter ascending axons mostly from the dorsal column pathway.

33. Area where axons ascend or desend several segments

34. A spot where fibers cross from one side to another

35. Lateral funiculus

40. Functional components
GSA—general somatic afferent—pain, vibration, touch, proprioception from skin, body wall, and skeletal muscle
GVA---general visceral afferent---pain, stretch from guts
GVE---general viscera efferent-----motor to viscera, glands, and blood vessels—autonomics
GSE---general somatic efferent----motor to skeletal muscle
SSA—special sensory afferent----vision, hearing, and balance
SVA—special visceral afferent----taste and smell
SVE---special visceral efferent—innervates muscle of branchiomeric origin—”gills”—pharynx, larynx,mastication, and facial expression—5,7,9,10, and 11

41. These “columns of nuclei with specific functional components” maintain their location throughout the brainstem

42. sg

43. A valve for pain

44. sg np

45. sg np nd

46. sg np
iml nd

47. imm

48. SG NP
IML CN
IMM
SG= substantia gelatinosa, NP= nucleus pulposus, IML=intermediolateral cell column, CN= Clark’s nucleus, IMM= intermediomedial cell column

50. Ventral Horn
Motor neurons (IX) innervate skeletal muscle, are large alpha motor neurons, are termed lower motor neurons and “the final common pathway”
The phrenic nucleus is found in cervical ventral horn (C3,4,5 keeps the diaphragm alive )
The spinal accessory nucleus is found at C1-C6

51. Name the spinal cord level

52. Name the spinal cord level
Thoracic-note lateral horn