Sem 1 - Q - Vertebral Canal & Contents - Ligaments, Spinal Cord/Nerve roots, Meninges, Arerial Supply/Venous Drianage

Question 1

• Many ligaments associated with the vertebral canal incl:
  
  • * Anterior longitduinal ligament
  • * Posterior longitduinal ligament
  • * Ligamentum flavum
  • * Interspinous ligaments
  • * Supraspinous ligaments
  • * Intertransverse ligaments
  • * Nuchal ligament
• Which ligaments are of the vertebral arch&spinous processes?
• Which ligaments are of the vertebral body?

Answer 1

Vertebral arch - formed by the pedicle and laminae

• Ligaments of the vertebral arch and spinous processes:
  
  • * Ligamentum flavum
  • * Interspinous ligaments
  • * Supraspinpinous ligaments
  • * Intertransverse ligaments
  • * Nuchal ligament
• Ligaments of the vertebral body
  
  • * Anterior longitduinal ligament
  • * Posterior longitduinal ligament

Question 2

First lets focus on the two longitudinal ligaments Where does the anterior longituindal ligament run and where does it begin from?

Answer 2

The anterior longitduinal ligament runs on the anterolateral aspect of the vertebral body from skull to sacrum

Question 3

The anterior longitduinal ligament is made of 3 layers of dense collagen fibres How does the attachment of the deep and superficial fibres of the anterior longitduinal ligaments differ?

Answer 3

The deep fibres bind adjacent vertebrae together The superficial fibres span multiple vertebral segements

Question 4

The anterior longitduinal ligament runs the length of the vertebral column from skull to sacrum. It is made of 3 layers of dense collagen fibres with deep fibres binding adjacent vertebrae together and superficial fibres spanning multiple vertebral segments What is the primarily function of the anterior logntiduinal ligament?

Answer 4

This anteiror longitduinal ligament is the only ligament of the vertebral column to limit extension - only ligament to sit anterior to the vertebrae

Question 5

Where does the posterior longitudinal ligament run and from where?

Answer 5

The posterior longtiduinal ligament runs within the vertebral canal on the posterior aspect of the vertebral bodies from C2 to the sacrum

Question 6

Where does the posterior longitudinal ligament mainly attach? What often lies between the ligament and the bony surfaces?

Answer 6

It mainly attaches to the intervertebral discs and the margins of the vertebra Fat and vessels often lie between the ligament and the bony surfaces

Question 7

What are the two functions of the posterior longitudinal ligament? What is its main function?

Answer 7

Main function Prevent posterior herniation of the IV disc - this would cause spinal cord impingement Also weakly limits flexion of the vertebral column

Question 8

Anterior longitudinal ligament * Where does it attach? * Where does it run? * What do its deep and superficial fibres bind/span? * What its function

Answer 8

Anterior longitudinal ligament * Runs on the anterolateral aspect of the vertebral bodies from sull to sacrum * It has 3 layers of dense collagen fibres with the deep fibres binding adjacent vertebra and the superficial fibres spanning mutliple vertebral segements * It limits extension of the vertebral column

Question 9

Posterior longitudinal ligament * Where does it attach? * Where does it run? * What is often between it and the bone? * What is its function?

Answer 9

Posterior longitudinal ligament * Attaches to the IV discs and margins of the vertebra * Runs within the vertebral canal on the posterior aspect of the vertebral bodeis * Fat & vessels often lie between the ligament & bone * Prevents posterior herniation of the IV disc * Weakly limits flexion of the vertebral column

Question 10

What is the singular and plural of ligamenta flava?

Answer 10

Plural - Ligamenta flava Singular - Ligamentum flavum

Question 11

The anterior longitudinal ligament was composed of 3 layers of dense collagen fibres What type of fibres make up the ligamenta flava? What does the ligamenta flava connect?

Answer 11

The ligamentum flava is made of strong elastic fibres connecting the laminae of adjacent vertebrae

Question 12

What are the functions of the ligamentum flava?

Answer 12

The ligamenta flava helps maintain vertebral curvatures and reinforce the vertebral canal posteriorly It also limits flexion of the vertebral column

Question 13

What type of fibres make up the ligamenta flava? What does the ligamenta flava connect? What are the functions of the ligamentum flava?

Answer 13

• Ligamenta flava
• Singular - ligamentum flavum
• Made up of strong elastic fibres connecting laminae of adjacent vertebrae
• Functions to Maintain vertebral curvtures Reinforce vertebral canal posteriorly Limit flexion

Question 14

Ligaments of the Spinous and Transverse Processes * Interspinous ligaments * Supraspinous ligaments * Intertransverse ligaments * Nuchal ligament Describe the interspinous ligament?

Answer 14

The interspinous ligament connects adjacent spinous processes and is thin, weak and membranous ligament

Question 15

Describe the supraspinous ligament? Where does it begin?

Answer 15

Suprapsinous ligament is a tough cord-like strucutre connecting the tip of the spinous processes from C7 - sacrum

Question 16

Describe the intertransverse ligaments? What is the difference in the fibres in the cervical, thoracic and lumbar regions?

Answer 16

Intertrnavserse ligaments connect adjacent transverse processes In the cervical region the fibres are scattered In the thoracic regions the fibres are fibrous In the lumbar region the fibres are membranous

Question 17

What is the function of the: * Interpsinous ligaments (thin, weak membranous connect spinous processes)? * Supraspinous ligaments (tough cord like structure connecting tips of spinous processes from C7-sacrum)? * Intertransverse ligaments (connects adjacent transverse processes, cervical - scattered fibres, thoracic - fibrous, lumbar - membranous)?

Answer 17

Interspinous and supraspinous ligaments both act to limit flexion of the vertebral column Intertransverse ligaments act to limit flexion and lateral flexion of the vertebral column

Question 18

Desribe the nucal ligament and where its attachments

Answer 18

The nuchal ligament is a thickened fibroelastic tissue attaching from the external occipital protuberance and the posterior border of the foramen magnum to the spinous processes of C1-7 vertebrae

Question 19

What is continous with the nuchal ligament? What are the functions of the nuchal ligament?

Answer 19

The supraspinous ligament is continuous with the nuchal ligament Functions Important for muscle attachment and limits flexion of the vertebral column

Question 20

State again what the nuchal ligament is, its attachments, its continuation and its functions

Answer 20

Thickened fibroelastic tissue attaching from the external occipital protuberance and the posterior border of the foramen magnum to the spinous processes of C1-7 It is continous with the supraspinous ligament (C7 - sacrum) Functions - muscle attachment & limit flexion

Question 21

Where does the spinal cord run from? and what does it end in?

Answer 21

The spinal cord runs from the foramen magnum to L1/2 vertebral level where it end in a medullary cone (known as the conus medullaris)

Question 22

What are the two enlargements in the spinal cord? What are the nerves attaching to these enlargements in the spinal cord?

Answer 22

The cervical enlargement From C4-T1 supplies roots to spinal nerves that supply the upper limb The lumbosacral enlargment From L1 to S3 supplies roots to spinal nerves that supply the lower limb

Question 23

How are the spinal nerves numbered in relation to the vertebrae? How many vertebrae and how many spinal nerves are there?

Answer 23

The cervical spinal nerves are named after the vertebra below EXCEPT C8 as there is no 8th cervical vertebrae T1 to Co1 vertebrae are named after the vertebrae above Vertebrae - 33 (7,12,5,5,4) , Spinal nerves - 31 pairs (8,12,5,5,1)

Question 24

What is the remnant of the caudal part of the spinal cord known as? It is a continuation of the spinal cord made up of neural tissue and the coverings of the spinal cord (mater layers) and this anchors the spinal cord to the coccyx

Answer 24

This would be the filum terminale - anchors the spinal cord to the coccyx

Question 25

Which mater layer is the filum terminale thought to be a continuation of?

Answer 25

Thought to be a continuation of the pia mater

Question 26

The vertebral column grows much more rapidly than the spinal cord in the latter stages of development. Yherefore the spinal roots of the lower spinal cord levels will have to grow much longer to reach the interveterbal foramen of their level This results in a horses tail appearance of nerve roots known as what?

Answer 26

This is known as the cauda equina - extension of lumbar and sacral nerve roots beyond the termination of the spinal cord

Question 27

Image shows spinal cord and the cauda equina due to the lumbar and sacral spinal roots having to grow much longer to reach their intervertebral foramen What are the three layers of protective tissue around the brain and spinal cord known as?

Answer 27

The meninges \* The dura mater \* The arachnoid mater \* The pia mater

Question 28

Which layer will extend over the nerve roots as the _____ root sheath? Which layer gives the spinal cord its shiny appearance and adheres tightly to the spinal cord?

Answer 28

The dura mater will extend over the nerve roots giving the dural root sheath The pia mater gives the spinal cord it shiny appearance and tightly adheres to the spinal cord

Question 29

Dura mater means tough mother Arachnoid mater means spider mother Pia mater means tender mother Describe the dura mater? Where does it attach inferiorly? What are the lateral extensions of the dura mater?

Answer 29

It is a tough outer covering attaching to the coccyx inferiorly by the filum terminale There are lateral extensions of spinal dura covering the nerve roots as Dural Root Sheaths

Question 30

What is the space between the dura mater and the bone?

Answer 30

This is the epidural space - it contains epidural fat and an internal vertebral venous plexus

Question 31

In life the arachnoid mater is held against the dura mater due to the pressure created by the fluid filled subarachnoid space In death, due to this pressure holding the arachnoid mater to the dura not being present, you are able to tease apart the arachnoid and dura mater What connects the arachnoid mater to the pia mater?

Answer 31

This would be the arachnoid trabeculae The arachnoid trabeculae are delicate strands of connective tissue that loosely connect the two innermost layers of the meninges – the arachnoid mater and the pia mater.

Question 32

As said before the subarachnoid space (between the pia and arachnoid mater) causes pressure holding the arachnoid to the dura mater What is the fluid in the subarachnoid space? What is the expansion of the subarachnoid space aound the conus medullarus to where known as?

Answer 32

Fluid in the subarachnoid space is CSF (cerebrospinal fluid) Expansion of the subarachnoid space around the conus medullaris exentending to S2 is known as the lumbar cistern LUMBAR CISTERN - L2 - S2

Question 33

What is the dural sac?

Answer 33

The thecal sac or dural sac is the membranous sheath or tube of dura mater that surrounds the spinal cord and the cauda equina.

Question 34

The spinal pia mater covers the spinal cord, nerve roots and spinal blood vessels What are the extensions from the pia mater known as? Where do they attach to?

Answer 34

These extensions would be the denticulate ligaments These are lateral extensions of the pia mater running between the anterior and posterior nerve roots and attaching to the dural mater to suspend the cord in the dural sac

Question 35

Image shows the denticulate ligaments separating the anterior and posterior roots What is the arterial supply to the spinal cord? Where do they arise from?

Answer 35

Have the anterior spinal artery - arising from the vetebral arteries Have the posterior spinal arteries (x2) - arising from the posterior inferior cerebellar artery (these are branches from the vertebral arteries)

Question 36

On the anterior and posterior aspect – have the anterior and posterior longtiduinal arteries – these run the length of the spinal cord from where to where? What arterial supply to the spinal cord supports these arteries? What small branches help supply the nerve roots?

Answer 36

The anterior and posterior (x2) longitudinal arteries run the length of the spinal cord from the medulla oblongata to the conus medullaris These arteries are supported by segmenetal arteries at different levels - help incase of longituindal artery blockage Small branches known as radicular arteries supply the nerve roots

Question 37

What is the drainage of the spinal cord?

Answer 37

There are 3 anterior and 3 posterior spinal veins forming an anastomasoses The anterior and posterior spinal veins are drained by the medullary and radicular veins

Question 38

What do the anastomosing anterior and posterior spinal veins drain into which lies in the epidural space?

Answer 38

The anterior and posterior spinal veins are drained by radicular and medullary veins which join the internal vertebral plexus of veins which lies in the epidural space