Vertebral Column 2 Flashcards
What is the anterior boundary of the spinal cord?
Vertebral body and posterior longitudinal ligament
What is the posterior boundary of the spinal cord?
Vertebral arches and the ligaments flava
Are there lateral openings in the vertebral column?
Yes, each vertebra contributes to half an opening
Are there lateral openings in the vertebral column?
Yes, each vertebra contributes to half an opening
What is the contents of the spinal cord?
Epidural fat pad
Internal venous plexus (within the fat pad)
Meninges of spinal cord
Cerebrospinal fluid
Spinal cord
Where is the external venous plexus located?
Outside the vertebral column, drains the back
Name the 3 membrane that surround the spinal cord as an extension from the brain
Dura mater
Arachnoid mater
Pia mater
Which is the most external membrane of the spinal cord?
Dura mater
Which is the most internal membrane of the spinal cord?
Pia mater
Which is the most internal membrane of the spinal cord?
Pia mater
Where is cerebrospinal fluid produced?
Choroid plexi of the lateral ventricles of the cerebrum
Where is cerebrospinal fluid produced?
Choroid plexi of the lateral ventricles of the cerebrum
Where does cerebrospinal fluid drain?
Into cerebral sinuses and roots of spinal nerves
What is the function of cerebrospinal fluid?
Cushioning of the brain and spinal cord
What is the overall name given to the membranes that surround the spinal cord?
Meninges
What is the overall name given to the membranes that surround the spinal cord?
Meninges
Where is the dura mater attached?
Periosteum of the skull
Foramen magnum
2nd sacral vertebra
Where is the dura mater attached?
Periosteum of the skull
Foramen magnum
2nd sacral vertebra
What separates the dura mater from the walls of the spinal canal?
Epidural fat pad
Layer of vessels
Where does the dura mater extend outside of the spinal canal?
It extends out of the intervertebral foramina with the spinal nerves
What is the space between the dura mater and arachnoid mater called?
Subdural space
What is the space between the dura mater and arachnoid mater called?
Subdural space
The dura mater is highly sensitive to ____
Pain
Where might blood accumulate after injury to the spinal cord?
Subdural space
Where might blood accumulate after injury to the spinal cord?
Subdural space
Describe the appearance of the arachnoid mater
Web like fascicles attach the arachnoid space to the pia mater
What is the space between the arachnoid mater and pia mater called?
Subarachnoid space
What is the subarachnoid space filled with?
Cerebrospinal fluid
What is the subarachnoid space filled with?
Cerebrospinal fluid
Which is the most difficult layer of meninges to dissect off the spinal cord?
Pia mater
Why does the pia mater have a pink ish appearance?
It is highly vascularised with many capillaries
Why does the pia mater have a pink ish appearance?
It is highly vascularised with many capillaries
How does the pia mater attach to the dura mater?
Through denticulate ligaments that piece through the arachnoid mater
What arteries supply the cervical region of the spine?
Vertebral arteries
What arteries supply the cervical region of the spine?
Vertebral arteries
What arteries supply the thoracic region of the spine?
Posterior intercostal arteries
What arteries supply the thoracic region of the spine?
Posterior intercostal arteries
What arteries supply the lumbar region of the spine?
Lumbar arteries
What arteries connect the lumbar arteries to the spinal arteries?
Radicular arteries
What do periosteal arteries supply?
Bone tissue and intervertebral discs
What do periosteal arteries supply?
Bone tissue and intervertebral discs
Which arteries give off the periosteal arteries?
Lumbar arteries
Which arteries give off the periosteal arteries?
Lumbar arteries
What does the internal venous plexus drain blood from?
Vertebral bodies and spinal cord
What does the internal venous plexus drain blood from?
Vertebral bodies and spinal cord
How is the internal venous plexus attached to the external venous plexus?
Connects via the intervertebral foramina
What veins drain the cervical region of the spine?
Vertebral veins
What veins drain the thoracic region of the spine?
Posterior intercostal veins
What veins drain the thoracic region of the spine?
Posterior intercostal veins
What veins drain the lumbar region of the spine?
Lumbar veins
What veins to do the internal venous plexus anastomose with?
Pelvic veins
Through which routes can blood flow from pelvic veins to the superior vena cava?
Through the azygous vein
Through the pelvic veins
Through which routes can blood flow from pelvic veins to the superior vena cava?
Through the azygous vein
Through the pelvic veins
How is the anastamoses of spinal and pelvic veins clinically important?
Abdominal and pelvic cancers can spread to the chest region through this route
Why is the vertebral column longer than the length of the spinal cord?
The musculoskeletal system has a longer growth period than the neural structures
Why is the vertebral column longer than the length of the spinal cord?
The musculoskeletal system has a longer growth period than the neural structures
At what spinal level is conus medullaris in neonates?
L3/4
At what spinal levels is conus medullaris in adults?
L1/2
Which body systems develop fast after birth?
Lung and cardiovascular systems
Which body systems take longer to mature at an older age?
Reproductive systems
What does the enlargement at the lower end of the cervical region and upper end of thoracic region tend to innervate?
Upper limb
What does the lower end of the thoracic region and upper end of the lumbar region tend to innervate?
Lower limb
What does the caudal equina refer to?
Refers to the nerves emerging rom he lumbar and sacral segments having the appearance of a ‘horsetail’
What is the filum terminale?
An extended strand of pia mater that emerges through the arachnoid mater to attach to the sacrum at the level of S2
Why does the lumbar cistern form?
The dura and arachnoid mater extend with the filum terminale, which forms a large sub arachnoid space
What is contained within the lumbar cistern?
Cerebrospinal fluid
Do spinal nerves always remain level with their respective vertebrae?
Not always.
Cervical region this applies, but nerves of the lumbar and sacral regions strongly deviate from their vertebral levels
List 3 uses of the lumbar cistern extending past the end of the spinal cord?
1- to take samples of CSF
2- to introduce contrast agents
3- to administer anaesthetic and analgesic blocks
Where does the safe space to insert a needle into the vertebral column end?
At the spinal level of L1
Where does the safe space to insert a needle into the vertebral column end?
At the spinal level of L1
Describe spinal anaesthesia
Anaesthetic agent injected into the subarachnoid space into the cerebrospinal fluid
What surgeries is spinal anaesthesia suitable for?
Surgery of the lower abdomen, pelvis and lower limbs
Is spinal anaesthetic slow or fast acting?
It is a fast acting anaesthetic
Describe epidural anaesthesia
Anaesthetic agent injected into the epidural space around the epidural fat pack (does not puncture any meninges)
Is epidural anaesthetic fast or slow acting?
It is a slow acting anaesthetic agent, so larger amounts of agent fluid is required
What is the main near-muscular different between spinal and epidural anaesthetic?
In spinal both pain and muscle control are lost
In epidural only pain is removed the muscle control still remains (important in child birth)
Describe what happens in a disc protrusion
Annulus fibrosus bulges into the vertebral canal, nucleus pulposus still intact
Describe what happens in a disc herniation
Nucleus pulposus herniates through the annulus fibrosus and into the vertebral canal
Which is more serious, an anterior to posterior disc herniation?
Posterior disc herniation is more dangerous as there are more structures that can be affected
Why are anterior disc herniations less common?
Presence of anterior and posterior longitudinal ligaments prevent them from occurring - even when they do occur they do not cause much pain
Which regions of the spine are more common for herniations?
Cervical
Lumbar
If nerve root C5 is herniated what muscles are affected?
Deltoid
Biceps brachii
If nerve root C5 is herniated what sensory is affected?
Lateral arm (axillary nerve)
If nerve root C6 is herniated what muscles are affected?
Biceps brachii
Wrist extensors
If nerve root C6 is herniated what sensory is affected?
Lateral border of forearm, digit 1 (lateral ante brachial cutaneous nerve)
If nerve root C7 is herniated what muscles are affected?
Triceps
Wrist flexors
Finger extensors
If nerve root C7 is herniated what sensory is affected?
Digits 2, 3, 4
If nerve root C7 is herniated what sensory is affected?
Digits 2, 3, 4
If nerve root C8 is herniated what muscles are affected?
Intrinsic muscles of hand
Flexors of fingers
If nerve root C8 is herniated what sensory is affected?
Medial border of forearm, digit 5 (medial ante brachial cutaneous nerve)
If nerve root T1 is herniated what muscles are affected?
Intrinsic muscles of the hand
If nerve root T1 is herniated what sensory is affected?
Medial border of arm (medial brachial cutaneous nerve)
If nerve root L4 is herniated what muscles are affected?
Tibialis anterior
If nerve root L4 is herniated what sensory is affected?
Medial aspect of leg
If nerve root L5 is herniated what muscles are affected?
Extensor hallucis longus
If nerve root L5 is herniated what sensory is affected?
Lateral aspect of leg
Middle of the dorsal part of foot
Digits 2, 3, 4
If nerve root S1 is herniated what muscles are affected?
Fibularis longus
Fibularis brevis
If nerve root S1 is herniated what sensory is affected?
Lateral aspect of foot
What action of the hip does L2+3 have?
Flexion of hip joint
L4+5 carry out _________ of the hip joint
Extension
L3+4 carry out extension of the ____ joint
Knee
Which dermatomes carry out the action of flexion of the knee joint?
L1+5
What action of the ankle does L4+5 have?
Dorsiflexion
L1+2 carry out _______ _______ of the ankle joint
Plantar flexion
Which nerve root does the bicep reflex test?
C6
Which nerve root does the triceps reflex test?
C7
The quadriceps tendon jerk reflex tests the __ reflex
L3
The achilles tendon reflex tests the __ reflex
S1
