4 Covering of the Spinal Cord Neuroanatomy 4 Dr Ahmed Kamal — Transcript

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1. 0:02The covering of the spinal cord, which
2. 0:06we call the meninges. They are the
3. 0:11membranes surrounding the spinal cord
4. 0:13and the brain. That protect them.
5. 0:16Protecting the spinal cord and
6. 0:17protecting the brain. Which we learned
7. 0:19about long ago in biology. The pia
8. 0:21mater, the arachnoid mater, and the
9. 0:24dura mater. So, these are the three
10. 0:27membranes covering the spinal cord. The
11. 0:30first one is this light blue one. This
12. 0:35is what we call the pia mater. Number
13. 0:38one is the pia mater. It is stuck
14. 0:41directly to the spinal cord, that is
15. 0:43the pia mater. After that, I find
16. 0:45another layer. Which is this light
17. 0:48green one. It is called the arachnoid
18. 0:52mater. This is called the arachnoid
19. 0:53mater. Then, on the very outside, I
20. 0:57find the outer layer, which is the dura
21. 1:00mater. So the meninges or the covering
22. 1:03of the spinal cord include the pia
23. 1:05mater. And this is right against the
24. 1:08spinal cord. Meaning it surrounds the
25. 1:10spinal cord. Then there is the
26. 1:12arachnoid mater, which is this. And
27. 1:16then there is the dura mater. Between
28. 1:18the pia mater and the arachnoid mater,
29. 1:21there is a space here. Meaning a
30. 1:24distance between the pia mater and the
31. 1:26arachnoid mater. This is called the
32. 1:28subarachnoid space. And this is where
33. 1:30the CSF flows or is found. Which is the
34. 1:34cerebrospinal fluid. Or the fluid that
35. 1:37surrounds the spinal cord and protects
36. 1:40it from shocks. So the spinal cord has
37. 1:43three meninges. Pia mater, arachnoid
38. 1:45mater, and dura mater. The exam
39. 1:48question is, where do these meninges
40. 1:52end? So here is the spinal cord. The
41. 1:56first layer is called the pia mater.
42. 1:58This dotted layer is called the
43. 2:00arachnoid mater. The layer after it is
44. 2:02called the dura mater. The pia mater
45. 2:04adheres to the spinal cord, it is stuck
46. 2:07to it. And then it emerges, ending with
47. 2:11the end of the spinal cord. Meaning the
48. 2:15pia mater ends opposite the lower
49. 2:17border of the first lumbar vertebra. Or
50. 2:20the upper border of the second lumbar
51. 2:22vertebra. And from it extends a thin
52. 2:25cord. This thin cord is called the
53. 2:29filum terminale or filum terminalis. It
54. 2:32attaches to the tip of, yes, it
55. 2:34attaches to the coccyx. It attaches to
56. 2:37the coccyx and. As we see here, it goes
57. 2:40down to attach where? To the coccyx. So
58. 2:43this is what they call the filum
59. 2:44terminale. Coming up next, this filum
60. 2:48terminale is an extension of the pia
61. 2:50mater. An extension of the pia mater.
62. 2:53Next, the dotted arachnoid mater and
63. 2:56the dura mater following it. Continue
64. 3:00downward and end at S2, the second
65. 3:02sacral vertebra. Here is the second
66. 3:05sacral vertebra. So the pia mater ends
67. 3:08at the first or the second lumbar
68. 3:11vertebra. And its extension is called
69. 3:13the filum terminale, which attaches to
70. 3:15the coccyx. And the dura and arachnoid
71. 3:18mater end at the S2, of course, the
72. 3:21threads descending here are those we
73. 3:23mentioned before. The roots of the
74. 3:27lumbar and sacral nerves. And they form
75. 3:30something for me called the cauda
76. 3:31equina. So these are what we call the
77. 3:33cauda equina. So do not forget the
78. 3:35sentence that. , here you extract it,
79. 3:46extension attaches next to the coccyx.