Neuroanatomy (2)

• Anatomy of the Spinal Cord Diagram

  
• What is the Spinal Cord? Define it in simple terms.


  - it is a bundle of nerve fibres that run down the vertebral column.

  
• The spinal cord begins from the...

  - brain stem.

  
  

  (the spinal cord is continuous with the medulla oblongata of the brain stem).

  
• The spinal cord runs through...

  - the vertebral column (specifically the vertebral foramen)

  
• The spinal cord runs from where to where?

  - it commences at the foramen magnum (of the occipital bone); and terminates at approximately the L1/L2 vertebrae.

  
• The spinal cord, like other CNS structures, is made of...

  GREY & WHITE MATTER.

  
  

  (grey matter is located inside (internal) & white matter is located on the outside (external))

  
• What is the main FUNCTION of the spinal cord?


  - To relay information / connections between the BRAIN and the PERIPHERAL NERVOUS SYSTEM (rest of the body).

  
• Diagram of the Spinal Nerves:

  
• Pairs of SPINAL NERVES emerge / come off the spinal cord to control...


  - different functions in the body.

  
• The SPINAL NERVES pass SENSORY information from _____________ to __________ .

  - pass sensory information from peripheries to the central nervous system (CNS).

  
• The SPINAL NERVES pass MOTOR information from _____________ to ____________ .


  - pass motor information from the central nervous system (CNS) to the peripheries.

  
• How many nerve pairs are there in the CERVICAL region?


  8

  
• How many nerve pairs are there in the THORACIC region?


  12

  
• How many nerve pairs are there in the LUMBAR region?


  5

  
• How many nerve pairs are there in the SACRAL region?


  5

  
• There is only ___ nerve pair in the COCCYX region:

  - ONE.

  (called the coccygeal nerve).

  
• What is the Cauda Equina?


  - they are a bundle of nerve roots at the LOWER end of the spinal cord (at the level of L1/L2).

  
  

  - they occupy the vertebral canal from L2 to S5.

  
• The cauda equina is involved in...


  ◦ Provide motor function to pelvis and lower limbs

  ◦ Sensory innervation of perineum

  ◦ Innervation for the bladder

  
• What is cauda equina syndrome?


  - it is a medical emergency; compression / damage to the cauda equina area can result in pain, weakness & numbness in the lower part of the body.

  
  

  - diagnosed through MRI & would require surgical decompression.

  
• What is cauda equina syndrome usually caused by?


  ◦ Usually caused by disc herniation (or trauma, cancer etc).

  
• Functions of Grey & White matter in the spinal column:


  - GREY: processes information

  
  

  - WHITE: transmits information

  
• Briefly describe the BLOOD SUPPLY of the spinal cord.


  The spinal cord is supplied by the vertebral arteries:

  
  

  ◦ Anterior spinal artery

  ◦ Posterior spinal arteries (left and right)

  
  

  - These arteries travel in the subarachnoid space of the spinal cord.

  
• Can the spinal cord regenerate / HEAL itself?


  - NO.

  
  

  The spinal cord itself can't heal - the fibres won't be able to reconnect.
• What is ankylosing spondylitis? Briefly describe it.


  - inflammation of the spine.

  - it is an AUTOIMMUNE disease; a rheumatoid disease that can lead to bony bridges connecting the vertebrae (very painful).

  
• Ankylosing spondylitis can lead to...


  - can lead to osteoporosis and increased risk of circulatory/cerebrovascular disease.
• Diagram of the Meninges

  
• What is the MENINGES?


  - these are three connective tissue membranes covering and protecting the CNS (central nervous system; brain & spinal cord).

  
• The Meninges are split into 3 SECTIONS:


  Starting from the top:

  1. Dura mater

  2. Arachnoid mater

  3. Pia mater

  
• Diagram of the Dura Mater (of the meninges)

  
• What is the DURA MATER? Describe it in simple terms.


  - it is the outermost layer of the meninges; it is located directly underneath the bones of the skull and vertebral column.

  
  

  - it is thick, tough, and inextensible.
• How many layers does the DURA mater have?


  TWO.
• The dura mater consists of TWO layered sheets of connective tissue.

  
  

  Name the TWO layers of the DURA mater.

  - externa periosteal layer

  - deep meningeal layer

  
  

  (both cover the spinal cord too)

  
• The DURA mater has two distinct dural folds:


  - falx cerebri

  - tentorium cerebelli

  
• The falx cerebri (of the dura mater) separates the..


  - right and left cerebral hemispheres.

  
• The tentorium cerebelli (of the dura mater) seperates the...


  - separates the occipital lobe from the cerebellum/brainstem

  
• Which STRUCTURE separates the two layers of the dura mater (the externa periosteal layer & deep meningeal layer)?


  - the DURAL VENOUS SINUSES are located between the two layers of dura mater.

  
• The DURA mater is highly vascular. True or false?


  TRUE.

  
• Which structure is located between the cranium & DURA mater?


  - EXTRADURAL SPACE
• Venous System Dura Mater Diagram

  
• Diagram of the Arachnoid mater (of the meninges)