Spinal Cord

52 flashcards · Other · by Jared Blackwell

1. What does dorsal horn have?

   Sensory cell bodies.

2. What does ventral horn have?

   Motor cell bodies.

3. What does lateral horn have?

   Sympathetic cell bodies. Only at T1- L2. (parasym CN 3,7,9,10).

4. A herniated disc will first contact what?

   Lower motor neurons. Disc pushes against motor which pushes sensory to bone.

5. Dorsal root ganglion is derived from what?

   Neural Crest Cells.

6. Where are all fibers for touch & proprociption located?

   Posterior Column

7. Where are cell bodies for motor?

   Pre-central gyrus.

8. Where are cell bodies for sensory?

   Dorsal root ganglion (pseudounipolor)

9. Where are the preganglionic sympathetic fibers located?

   Lateral horn of thoracic spinal cord. Intermediate gray.

10. Is touch and proprioception for leg sensation in the spinal cord more medial or lateral?

    Touch and proprioception sensory for leg is more medial.

11. Is pain and temperature for leg sensation in the spinal cord medial or lateral?

    Pain and temperature sensory for leg is more lateral Spinothalamic tract results in leg being more latearl and arm more medial. Pain and temp go to postcentral gryus AND insula.

12. 1) Ipsilateral, cervical DRG. A: Posterior column, GC 2) Ipsilatearl, caudal medulla 3) Contralateral, Precentral Gyrus B: Lat. Corticospinal tract 4) Ipsilateral, Ventral Horn 5) Ipsilateral, DRG 6) Ipsilateral, Dorsal Horn 7) Contralateral, Dorsal Horn D: Spinothalamic tract 8) Ipsilateral, VPL Thalamus 9) Ipsilateral, muscle.

13. Where does all sensory information go to ?

    All sensory info goes to Thalamus; except smell.

14. Do lower motor neurons ever cross?

    Lower motor neurons NEVER cross.

15. Describe the blood supply to spinal cord

    Posterior has two anastomosis. Supplies posterior column -touch & proprioception. Anterior spinal artery ALL Lower and Upper motor neurons and Spinothalamic tracts (no pain or temp).

16. Level is? Lesion is? Patient phenotype?

    Lumbar Posterior Column (Fasiculis Gracilis) No cuneatus in lumbar. Loss of touch & proprioception in left leg same side-ipsilateral. **May be caused by Neurosyphilis not treated destroys myelin; hypoesthesia (diminished tactile and sensory) Diminished reflexes.

17. Level is? Lesion is? Patient phenotype?

    Cervical Posterior Column Loss of touch & proprioception in left leg and arm-ipsilateral.

18. Level is? Lesion is? Patient phenotype?

    Lumbar Spinothalamic tract Loss of pain & temperature right leg-contralateral side.

19. Level is? Lesion is? Patient phenotype?

    Cervical Lateral Corticospinal Tract (Lateral Funiculus). Upper Motor Neurons. -Hyperreflexia right arm and leg, increased muscle tone. -Weakness in right arm and leg. -Babinski right side-same side.

20. Level is? Lesion is? Patient phenotype?

    Cervical -Lateral Corticospinal Tract -Anterolateral Spinal Tract -Anterior horn -Spinothalamic tract -Right arm paraylsis, hypo-reflexia. LMN. -Hyperreflexia and babinski right leg. UMN. Did NOT lose LMN in leg. -Loss of pain/temp in left arm and leg (spinothalamic tract). **If this happened in Lumbar, would lose LMN in legs as well, hypo-reflexia.

21. Level is? Lesion is? Patient phenotype?

    Cervical Left half of spinal cord (Brown Sequard). -Left arm weakness, atropy, hyporeflex -Left leg hyperreflexia, increased tone, Babinski. -Right arm, body, leg loss of pain/temp. -Left arm, body, leg loss of touch/prop. -Left arm at level of injury: loss of pain/temp.

22. Level is? Lesion is? Patient phenotype?

23. Level is? Lesion is? Patient phenotype?

    Lumbar Anterior Spinal Artery Bilateral leg weakness, atrophy, hyporeflexia. Loss of pain/temp. bilateral legs.

24. Describe intrafusal & extrafusal fibers

    Intrafusal Non-contractile. Proprioception. Gamma motor neurons inv. to maintain length. At end of intrafusal muscle. Spreads intrafusal fiber w/ contraction to maintain proprioception. Extrafusal Contractile Alpha motor neurons.

25. Difference in Primary 1a and Secondary 2 nerve fibers in muscle?

    Primary 1a = dynamic muscle movement. Go into intrafusal fibers. Secondary 2 = static muscle.

26. What is the PIEZO2 Receptor?

    Mechanoreceptor: Detects when muscle is moving. Defect: No proprioception. Extremely uncoordinated.

27. What does Golgi Tendon Organs do?

    Detect muscle tension. Slow adapting sensory fibers Ib. *Spindle fiber for length of muscle and Golgi tendon for tension.

28. Ia and Ib Meissner, Merkel, Pacinian A-beta Axons to intrafusal fibers-gamma motor neurons. Sharp pain, cold, some touch A-delta Preganglionic Slow pain, heat, itch, some touch C Postganglionic autonomic.

29. What type of sensation gets to body fastest and slowest?

    Proprioception Fastest. Pain, heat, itch SLOWEST.

30. At sensory cortex-post central gyrus where would you feel things on face, hand, and leg?

    Face is at 9 o'clock, middle. Hand is at 10 o'clock, high Leg is at 12 o'clock, top middle. *Loss of sensory opposite side.

31. Describe pain pathway

    C fibers and delta fibers detect pain. LONG nerves travel to pseudounipolor DRG to spinal cord. Signal then goes to thalamus

32. Which are our pain fibers and describe them?

    Nociceptors C fiber Delta fiber C-fiber chemical, thermal, mechanical A-delta fiber mechanical and thermal. Medium, thinly-myelinated.

33. Describe peripheral nociceptor activation

    Chemical, mechanical, and thermal starts graded potential which reaches trigger zone and activates VGSC for AP. Periphery Nociceptor Activation "Axon Reflex" Nociceptors release things to provoke more pain. Recruits immune cells, vasodilation, edema.

34. What is the TRPV1 receptor?

    Acts like thermostat, gets to certain temperature then Na+ and Ca2+ influx.

35. What is Allodynia and Hyperalgesia?

    Allodynia is pain from normal stimuli. Sunburn Hyperalgesia is painful stimulus perceived as MORE painful.

36. Explain opoid disinhibition

    Opioids block VGCa2+ and open K+ to shut down neurons. GABA opens Cl- channels to hyperpolarize and shut down neuron. Opioids will shut off GABA and other neurons become excited (enkephalins, endorphins, serotonin, NE).

37. CADUAL MEDULLA Fasciculus cuneatus Nucleus cuneatus Fasciculus gracilis. Nucleus gracilis STT Pyramidal Decussation (no groove in the middle) Anterior horn Pyramid *Begin to see second order neurons i.e. NG and NC FG and FC are primary afferents.

38. Rostral Medulla - you can see the 4th ventricle. 4th ventricle MLF (medial longitudinal fasiculusucs keeps eyes moveing together). STT ML CST Inferior Olive Pyramid

39. Caudal Pons Know this b/c cerebellum is attached. 4th Ventricle MLF STT ML CST

40. Rostral Pons 4th ventricle MLF ML STT CST

41. Caudal Midbrain - Know this b/c aqueduct.

42. Rostral Midbrain Cerebral peduncle well developed.

43. Midbrain always has aqeuduct. Pons has 4th ventricle which slightly travels down to Medulla.

44. Midbrain Pons Medulla Pyramids, axons of Upper Motor Neurons end at last arrow (end of brainstem). The UMN cross at last arrow.

45. Interpeduncle cistern Cistern is collection of fluid-CSF. Pontomedullary Junction Between Pons and Medulla CN 7, 8, 9 come out. Pyramids- contain UMN axons.

46. Midbrain has the Tectum or Quadrigeminal Plate-"4 bumps" Important for vision and hearing. Superior and inferior colliculus. Tectum means "roof" Caudal pons attaches to cerebellum

47. Midbrain 3, 4 Pons 5, 6 Pontomedullary Junction 7, 8 Medulla 9, 10, 12 Vagus allows below bumps pyramid. 12 between pyramid and olive. Spinal accessory comes from cervical SC.

48. Rostral Medulla Solitary tract CN 7, 9, 10 goes to geniculate ganglia and then goes to solitary tract in medulla. *Solitary tract is still primary afferent. The nucleus right above solitary tract is where second order neurons are (white above point of arrow).

49. Describe CN VII in the brainstem

    Motor for facial expression is at CN 7 nucleus. Just above is the SSN for parasympathetic function. The axons travel up and slightly medial to where CN 6 nucleus is. Often times, both CN 6 7 are injured together.

50. Rostral Medulla Dorsal Motor Nucleus of Vagus X (DMN-X) autonomic efferent with most of preganglionic parasympathetic neurons for thoracic and abdominal viscera. Nucleus Ambiguus (NA) collection of LMNs for larygeal and pharygeal muscles.

51. Cingulate Gyrus Corpus Collosum Septal Nuceli Fornex Red is Anterior Commisure comminucation temporal lobe to temporal lobe Basal Nucleus Blue is internal capsule. Globus palludus medial to Putamen. Insula is black arrow on left. Detects Pain and Gustatory.

52. A stroke in the Anterior Cerebral Artery affects what? Stroke in Middle cerebral artery?

    Anterior cerebral artery affects leg. Middle cerebral artery affects arm or face.