BMC L6 Flashcards
Cross section of the spinal cord and vertebra
- Pia mater
- Arachnoid mater
- Dura mater
- Dorsal root ganglon
- Subarachnoid space (contains CSF)
- Subdural space
- Epidural space (contains fat)
State the role of filum terminale
Extends distally from the menginges
Attaches to coccyx
Anchors the spinal cord to the meninges
Describe the location of the dura mater of the spinal cord
Extends from the magnum foramen to the filum terminale
SPINAL NERVES RUN THROUGH DURA MATER
DURA MATER SURROUNDS NERVE ROOT
AND FUSES WITH EPINEURIUM
Describe the spinal cord external anatomy
SC begins at the occipital bone
SC ends as cauda equina at veterbal junction L1/L2
Describe the cervical enlargement of the spinal cord
In the cervical region of the spinal cord, there is a section where it is enlarged, between C4 and T1, this is because the nerves serving arms emerge / leave from here
C4 to T1
Nerves serving arms emerge here
Describe the Lumbar enlargement of the spinal cord
T11 to L2
Nerves serving legs emerge here
State two functions of the spinal cord
2-way communication between CNS and PNS
Contains spinal reflex centre
What is the cauda equina?
Collection of nerve roots at inferioir end of vertebral canal
What is cauda equina syndrome? Symptoms and Cause
Symptoms:
- Low back pain, radiating down legs
-Numbness around anus therefore, loss of bowel and bladder control
Cause:
Disk herniation / cancer / trauma / epidural hematoma
Describe the internal anatomy of the spinal cord
Grey matter inside, white matter outside
2 grooves divide cord into right and left halves
What are the two grooves which divide the spinal cord into right and left halves?
Ventral median fissure / anterior
Dorsal median sulcus / posterior
What structure connects the left and right grey areas
Grey commisure
Describe the distrobution of grey matter within each side of the spinal cord
Grey matter on each side of spinal cord is subdivided into regions called horns:
- Dorsal horns (posterior horn): interneurones
- Lateral horns: part of symp ANS, present in throracic and L1 and L2, motor neurones to SM and glands
DIAGRAM
3. Ventral horns (anterior horn) - somatic efferents - voluntary movements
Describe the simplified spinal reflex
How many spinal nerves are there?
31 pairs of spinal nerves
- 8 cervical nerves
-12 thoracic nerves
-5 lumbar nerves
-5 sacral nerves
-1coccygeal nerve
NOTE: 8 cervical nerves, 7 cervical vertebrae
How to spinal nerves travel through the spinal cord?
Pass in/out superior to corresponding vertebrae via intervertebral foramen
What is the white matter of the spinal cord?
Contains bundles of nerve axons - organised into TRACTS / FASCICLES
Grouped into 3 white columns (funiculi) on each side
DORSAL, VENTRAL, LATERAL FUNICULI
Allow comunication with CNS
May be ascending / descending tracts
(ascending - sensory)
(descending - motor)
State two types of descending tracts
- Direct pathways / pyramidal tracts
VOLUNARY MOVEMENT
Parkinson’s disease - Indirect pathways / extrapyramidal tracts
PREVENTS UNWANTED MOVEMENT
Huntington’s Chorea
State the function of descending tracts
Deliver EFFERENT impulses
Brain to spinal cord
What are the two types of spinal cord injuries
Can be complete / incomplete
Give examples of complete spinal cord injuries
- Quadriplegia
Cervical regions
Affects all 4 extremities - Paraplegia
Thoracic and Lumbar, sacral regions
Affects only 2 extremities
Give examples of incomplete spinal cord injuries
- Central cord syndrome
- Anterior cord syndrome
- Posterior cord syndrome
- CAUDA EQUINA SYNDROME
State the most common causes of spinal cord injuries
Fall
Assult
Sport
Degenerative causes
Tumours
Cancer
Disk herniation
Epidural Hematoma
Describe the location / position of the spinal cord
Spinal cord located in vertebral canal in vertebral column
Describe the vertebral column
Series of bones called vertebrae, separated by intervertebral disks
vertebral column divided into 5 regions:
- Cervical 7
- Thoracic 12
- Lumbar 5
- Sacrum 5
- Coccyx 4
State which two vertebrae in the vertebral columnn are fused
Sacrum and coccyx
State the two topmost vertebrae and its function
Atlas c1 and axis c2
Form joint, connecting skull and spine
atlas and axis work together to help rotate the neck
How are the two topmost vertebrae specialised to their function
Specialised to allow greater range of motion than any other vertebrae
GREATER MOTION / MORE MOVEMENT
State the cause of lordosis
SWAYBACK
EXCESS ANTERIOIR CURVATURE OF LUMBAR VERTERBAL COLUMN REGION
common in pregnant women to PROTECT SPINAL CORD
Describe the magnum foramen
“big hole”
where spinal cord enters to join to skull
Describe the occipital condyle
Joint between C1 and skull
Tracts (ascending + descending) can only be white matter
Because they are axons
State the two ascending tracts
Spinothalamic tract
Dorsal White Column tract
