Spinal Cord & Meninges Flashcards
(27 cards)
What makes up the meninges, moving from the most superficial towards the deepest?
Dura mater
Arachnoid mater
Subarachnoid space
Pia mater
What type of joint is between the superior and inferior articular facets?
Zygophysial
Where do the spinal nerves exit from?
Intervertebral foramen
Where is it safe to do a lumbar puncture and why?
L3/L4
The spinal cord stops at L1/L2
Where does the Supraspinous ligament stretches from and where does it stop?
What is its function?
C7 to all the way down
Prevents extreme flexion/extension/rotation
What does the spinal cord continue as once in the skull?
Medulla oblangata
What is the inferior end of the spinal cord called?
Conus medullaris, which narrows as filum terminale
What two parts make up the filum terminale?
Filum terminale internum
Filum terminale externum
What is occipital condyle?
The joint where C1 (Atlas) joins the skull
What makes up the filum terminale externum and what is its function?
The arachnoid and dura mater join together to from the filum terminale externum - this attaches nerves to the coccyx
What is the enlarged subarachnoid space in the lumbar region called?
Lumbar cistern
What are the two spinal cord enlargements, where are they and what are they due to?
Cervical enlargement (brachial plexus)
- C4-T1
- due to more grey and white matter since upper limb nerves join the spinal cord at that point
Lumbosacral enlargement (lumbosacral plexus)
- T11-S1
- due to more grey and white matter since lower limb nerves join the spinal cord at that point
How does the growth of the spinal cord and vertebral column compare?
The vertebral column grows faster than the spinal cord
What symptoms could arise after a lumbar puncture?
Headaches
- due to the change in interspinal/intercranious pressures
- drinking lots of water and some coffee helps
Describe the transverse/cross section of the spinal cord?
White Matter
- Dorsal Column
- Lateral Column
- Anterior Column
Grey Matter
- Dorsal Horn
- Lateral Horn
- Ventral Horn
Anterior and Posterior/Dorsal median fissures
- behind them are important blood vessels
Central canal
- CSF goes through it
Anterior White Commissure
- Axons cross here
Describe the spinal roots and ganglia
- Anterior root (motor fibres)
- Posterior root (sensory fibres)
- Spinal/dorsal root ganglion
- Spinal nerve (short)
- Dorsal ramus (supplying the back)
- Ventral ramus (supplying structures laterally and anteriorly)
- Sympathetic trunk
- Rami communicantes (links sympathetic trunk and anterior ramus together)
How are the arachnoid and pia mater linked together?
Via arachnoid trabeculae (delicate strand of connective tissue)
Describe the dura mater
- Most outer layer, thick and hard
- Made up of two layers in the cranium: meningeal and dura; meningeal stops at the foramen magnum
- Ends at S2 where it fuses with filum terminale externum which then attaches nerves to the coccyx
- Covers the spinal nerves as they pass through the intervertebral foramen
Describe the arachnoid mater
- Delicate, avascular middle layer
- Connects to pia via arachnoid trabeculae
- Ends at S2
- Encloses subarachnoid space between arachnoid and pia, which encloses the caudal equina as lumbar cistern
Describe the pie mater
- This, innermost vascular layer
- Covers the surface of the brain, spinal cord and spinal roots
- Becomes the filum terminale externum, attaching to the coccyx
- Triangular extensions of pia called denticulate ligaments attach to the arachnoid mater and suspend the spinal cord in the space
What is between the meningeal layers of the spinal cord and the bony part of the vertebral foramen?
Describe it
Extradural space
- Fatty matrix
- Runs from the foramen magnum to the sacral hiatus
- Internal to periostium covering the bone
- Contains internal vertebral venous plexus
Describe the blood supply of the spinal cord
Two sets of arteries:
3 longitudinal arteries - branches of the vertebral arteries:
- anterior longitudinal artery (in anterior media fissure; gives off sulcal arteries)
- posterior longitudinal arteries (2 paired)
- lie on surface of the cord, come from the foramen mangum and go all the way down
Numerous segmental arteries:
- branches of the aorta
- – cervical: from vertberal arteries
- – thoracic: from intercostal arteries
- – lumbar: from lumbar arteries
- help out longitudinal arteries
- enter vertebral canal via intervertebral foramina
What are the branches of the arch of the aorta?
Brachiocephalic artery - Right subclavian artery --- Vertebral artery on spinal cord - Right common carotid artery Left common carotid artery Left subclavian artery
Describe the vertebral artery around the spinal cord
- Enters via the foramen transversaria of the cervical vertebrae
- Gives off longitudinal arteries/branches at the foramen magnum
