The meninges are three layers of tissue that surround and protect the spinal cord. The outermost layer is the dura mater, which forms a protective sheath. Inside is the arachnoid mater, separated from the inner pia mater by cerebrospinal fluid in the subarachnoid space. The pia mater is highly vascular and adheres closely to the spinal cord. Together these layers cushion and support the spinal cord while allowing for blood vessel and nerve passage.

1. Meninges Of Spinal Cord
Content:
• Introduction to spinal cord
• Brief introduction to meninges.
• Meninges of spinal cord.
• Dura mater.
• Arachnoid mater
• Pia mater
• Clinical notes.
MADE BY: AQSA KIRAN.
CLASS: DPT-4(2018)

2. SPINAL CORD
The spinal cord is a long, thin, tubular structure made up
of nervous tissue, which extends from the medulla
oblongata in the brainstem to the lumbar region of the
vertebral column.
• The brain and spinal cord together make up the central nervous
system (CNS).
• The spinal cord functions primarily in the transmission of nerve signals
from the motor cortex to the body, and from the afferent fibers of the
sensory neurons to the sensory cortex.
• The spinal cord is protected by three layers of tissue or membranes
called meninges, that surround the canal .

4. Meninges
The meninges is a layered unit of membranous connective
tissue that covers the brain and spinal cord.
 These coverings encase central nervous system structures so that they are
not in direct contact with the bones of the spinal column or skull.
 The term 'meninges' (singular: meninx) is derived from the Greek word for
membrane.
 The meninges are composed of three membrane layers
1. Dura mater.
2. Arachnoid mater.
3. Pia mater.

6. Functions of meninges
1. Its primary function is to protect and support the central
nervous system (CNS).
2. It connects the brain and spinal cord to the skull and
spinal canal.
3. The meninges forms a protective barrier that safeguards
the sensitive organs of the CNS against trauma.
4. It produces cerebrospinal fluid.

7. Meninges of spinal cord
Spinal cord in vertebral column is protected by three layers of
meninges.
1. Dura Mater 2. Arachnoid Mater 3. Pia Mater.
The meningeal layer continuous above through the foramen
magnum with the meningeal layer of dura covering the brain and
ends on the filum terminale at the lower border of second sacral
vertebra.

8. Dura mater
 It is the outer most meningeal covering of spinal cord.
 The spinal dura mater is only compose of Dural meningeal layer
means unlike brain dura mater it do not have Dural periosteal
layer.
 It forms the Dural sac that envelopes the cauda equine of the
spinal cord and extends downward together with the filum
terminale to the periosteum of the coccyx.
 Filum terminale: it is the thread of connective tissue and the
point at which the spinal cord ends.

9.  It is the thickest and toughest of all three layers.
 It derived from the mesoderm in the embryonic developments.
 The dura mater contributes to the subdural and epidural spaces.
Subdural space:
The space between dura mater and arachnoid mater is
called subdural space.
Epidural space:
Dura mater is separated from the walls of the vertebral
canal by the epidural space.
• This space contains some loose connective tissue, and the internal
vertebral venous plexus.
• the spinal nerves exit the vertebral canal, they pierce the dura mater,
temporarily passing in the epidural space.

11. Dural sheath
An extension of the dura mater that surrounds the spinal nerves of
the spinal cord.
 The Dural sheath extends beyond the end of the spinal cord, creating a cavity
known as the lumbar cistern.

12. Arachnoid mater
It is the middle layer of meninges inferior to dura mater and
superior to pia mater.
 It is a delicate membrane, impermeable and avascular membrane.
 It is separated from the pia mater by subarachnoid space.
subarachnoid space:
• It contains the arachnoid trabeculae ( thin fibrous filaments that
holds the two layer in there place.)
• It is filled with CSF.
• It provides the pathway for CSF circulation and absorption.
• Roots of spinal roots, arteries and veins passes through this space.

14. Pia mater
The spinal pia mater is the innermost of the meninges. It is a thin
membrane that covers the spinal cord, nerve roots and their blood
vessels. Inferiorly, the spinal pia mater fuses with the filum
terminale.
 Between the nerve roots, the pia mater thickens to form the
denticulate ligaments.
 It is the highly vascular layer.
 Ligamentum denticulatum passes laterally to adhere to the
arachnoid and dura mater. Due to this the spinal cord is suspended
in the middle of the Dural sheath.

16. Clinical notes
1. Lumber punchers:
The elongation of the spinal dura mater past the
termination of spinal cord allows for the retrieval of cerebrospinal fluid
from this area. This is known as lumber punchers.
2. Meningitis:
An inflammation of the meninges, the membranes that
surround the spinal cord.
3. Head ach:
stretching of dura mater results in head ach.