this will be beneficial for bsc nursing and msc nursing students

1. SPINAL NERVES
By : Vipin Chandran
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2. Spinal Nerve
• Spinal nerve are the path of communication
between the spinal cord and the specific region
of the body
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3. Spinal Nerve
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31 pairs
Spinal nerve follows the name of corresponding
vertebra column.
Consists cervical spinal nerve, thoracic spinal nerve,
lumbar spinal nerve, sacral spinal nerve and coccyx
spinal nerve.
Emerge from spinal cord and through the
intervertebral foramina of vertebra.
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4. Spinal Nerve
• Spinal nerves:
1. 8 pairs of cervical spinal
nerves
2. 12 pairs of thoracic spinal
nerves
3. 5 pairs of lumbar spinal
nerves.
4. 5 pairs of sacral spinal nerves
5. 1 pairs of coccyx spinal
nerves.
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5. Spinal Nerve
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• Cervical and thoracic spinal nerves arise and leave at
corresponding vertebra .
Because the spinal cord are shorter than vertebra
column, nerve that arise from lumbar, sacral and
coccyx region of spinal cord do not leave the
vertebral column at the same level where they exit
the cord.
The root of these spinal nerves angle inferiorly in the
vertebral canal from the end of spinal cord like wisps
of hair.
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6. Spinal Nerves
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7. • These root of this nerve, collectively called cauda
equina.
Typical spinal nerve has 2 connection to spinal cord;
posterior / dorsal and anterior/ ventral root.
Posterior and anterior root unite to form spinal nerve at
intervertebral foramina.
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• Since posterior root contain sensory axons and
anterior root contain motor axons, spinal nerves is
classified as a mixed nerve.
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8. Spinal Nerves
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11. Spinal Nerves
Cervical spinal nerves
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8 Pairs
1st pair emerge between atlas and occipital bone
The remaining emerge from the vertebral column
through intervertebral foramina.
Spinal nerves C1 – C7 exits the vertebral canal
above their corresponding vertebra.
Spinal nerve C8 exits vertebral canal between C7
and T1
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12. Cervical Spinal Nerves
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13. Thoracic spinal nerve
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12 pairs
Exits the vertebral canal below their corresponding
vertebra.
Emerge from thoracic vertebra
Continuous to form intercostals nerves.
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Spinal Nerves
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14. Lumbar Spinal Nerve
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5 pairs
Emerge from lumbar vertebra.
Exits the vertebral canal below their corresponding
vertebra.
Spinal Nerves
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15. Sacral and Coccyx Spinal Nerve
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5 pairs
From the spinal cord, the root of the sacral spinal
nerve enter the sacral canal (part of the vertebral
canal).
Sacral nerves (S1-S4) exits the vertebral canal via 4
pairs of anterior and posterior sacral foramen.
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Spinal Nerves
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16. Distribution of Spinal Nerve
Branches
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• From the root, after passing the intervetebral foramen,
a spinal nerve divide into several branches.
Theses branches are call rami (ramus) ; posterior
(dorsal) ramus and anterior (ventral) ramus.
Posterior (dorsal) ramus serve the deep muscles and
skin of the posterior surface of the trunk.
Anterior (ventral) ramus serve muscles and structure
of the upper and lower limbs and the skin of the lateral
and anterior surface of the trunk.
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18. Plexuses
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Network of axons is called plexuses.
The principle plexus:
1. Cervical plexus
2. Brachial plexus
3. Lumbar plexus
4. Sacral plexus
5. Coccygeal plexus
Distribution of Spinal Nerve
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20. Plexuses
Cervical Plexus
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• Formed by the roots of anterior rami of the 1st four
cervical nerve (C1-C4), with contribution from C5.
There is one on each side of the neck alongside the
first 4 cervical vertebrae.
Supply the skin (sensory / cutaneous innervations)
and muscles (motor innervations) of the:
 head,
 neck
 superior part of the shoulder and chest.
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22. Brachial Plexus
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• Form by roots of anterior rami of spinal nerves of
C5-C8 and T1.
Divides into roots, trunks, divisions, cords and
terminal branches (nerves).
5 important nerves arise from brachial plexus are
musculocutaneous, axillary, radial, ulnar and median
nerves.
Plexuses
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24. Lumbar Plexus
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• The roots of anterior rami of spinal nerves L1-L4
form lumbar plexus.
The main nerve is a femoral (the largest) and
obturator nerves.
Supply the skin and muscles of the:
– anterolateral abdominal wall
– external genitals (cremaster muscles, skin on
scrotum, labia majora etc)
Plexuses
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26. Sacral Plexus
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• Form by the roots of anterior rami of spinal nerves
L4-L5 and S1-S4.
This plexus is situated largely anterior to the sacrum
The largest nerve in the body, sciatic nerve arise
from the sacral plexus.
Supply the skin (sensory) and muscles (motor) of
the:
– Buttock
– Perineum
– Lower limbs
Plexuses
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28. Coccygeal Plexus
• Form from roots of anterior rami of spinal nerves S4
and S5 and the coccygeal nerves.
• Supplies a small area of skin in the coccygeal
region.
Plexuses
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