The Spine and Spinal Cord Flashcards
True or False: The brain stem connects the brain to the spinal cord
True
Which gender is known to have a longer spinal cord?
Average men: 45cm
Average women: 43cm
What are the three layers of the meninges?
Dura Mater, Arachnoid, Pia mater (DAP: Dogs always play)
What is the thickest layer of the mengines?
Dura mater (outermost layer)
What is the middle layer of the meninges?
Aracnoid
What is the innermost layer that adheres to the brain surface of the meninges?
Pia mater
What are the total segments of the spine?
33 segments
Define spinal segment
Region associated with one vertebra and one dorsal/ventral spinal nerve pair
How many segments are in the cervical?
7 segments
How many segments are in the thoracic?
12 segments
How many segments are in the lumbar?
5 segments
How many segments are in the sacral?
5 segments
How many segments are in the coccygeal?
4 segments
Name the 5 parts of the spinal cord
Cervical, Thoracic, Lumbar, Sacral, Coccygeal
What part of the body is within the cervical vertebrae?
Head, neck, shoulders, diaphram
What parts of the body are within the thoracic vertebrae?
Truck muscles, chest wall, organs
What parts of the body are within the lumbar vertebrae?
Lower back, legs, feet
What parts of the body are within the sacral vertebrae?
Bowel, bladder, sexual functions
What parts of the spinal cord are fused?
Sacral and Coccygeal
What is a dermatome?
An area of skin/ the body associated with a single spinal cord segment
What is clinical importance?
Specific region affected by pain or paralysis indicates nerve and spinal region that should be medically assessed.
Complete SCI:
No movement or sensation below injury
Incomplete SCI:
Partial damage to cord
Hangman’s fracture:
C2 usually fatal due to brain stem injury (medulla, reticular activating system)
Severing below brainstem, but above c3,c4,c5:
Usually leads to asphyxiation
Define Quadriplegia:
Loss of feeling in most of the body (four limbs)
Define paraplegia:
Loss of feeling in lower extremities
What has a similar consistency to the spinal cord
Toothpaste
Vertebral body is:
Anterior/ventral
Spinous process is:
Posterior/dorsal
Intervertreal disc is:
Spongy cushion, allows flexibility. “Slipped disc”
The vertebral body and Spinous Process in connected by:
Ligaments
Where would an epidural be placed during labor?
T10-L1 (midlumbar/lower back)
The subarachnoid space is between the:
Arachnoid mater and pia mater, contains CSF
The epidural space is located:
Outside of the meninges, mostly adipose tissue
Symptoms of meningitis is:
Inflammation of the meninges, headache, stiff neck, high fever.
Dorsal root is:
Sensory axons and interneuron cell bodies, ASCENDING
Ventral root is:
Motor cell bodies, DESCENDING
Dorsal information comes from:
In from the body to spinal cord through dorsal rootlets into dorsal root (sensory)
Dorsal rootlets enter the cord at the:
Posterolateral sulcus (postero = back)
Ventral information goes from:
From the spinal cord to body through ventral rootlets into ventral root (motor)
Central rootlets enter the cord at the:
Anterolateral sulcus (antero= front)
What does pseudounipolar neurons mean?
They have one long axon with two branches. Typically one branch extends peripherally from the muscle/skin while the other extends from the cell bodies at the ganglion towards the spinal cord)
True or False: dorsal root ganglion cells are pseudounipolar?
True
What are the two major subdivisions of the dorsal horn?
Substantia gelatinosa and Nucleus proprius
The substantia gelatinoa
Caps the horn; contains cell bodies from incoming sensory axons carrying pain and temperature information.
The nucleus proprius:
Contains cell bodies of interneurons and cell bodies entering axons with somatic and visceral proprioceptive information.
True of False: ventral horn contains a ventral root ganglion.
False: the motor cell bodies are all inside the ventral horn.
Dorsal nucleus:
Contains bodies of spinal neurons that receive proprioceptive information from the body, ultimately carrying it to the cerebellum. (AKA Clark’s nucleus)(T1-L2) SENSORY
Intermediolateral nucleus:
Contains spinal preganglionic autonomic neurons that send information to organs like the heart lungs and intestines. (T1-L3) MOTOR
Central canal carries what?
CSF
Cervical enlargment:
motor neurons to control arms/head/upper body
Lumbar enlargement:
Motor neurons to control legs/lower body
Spinal cord is _ thick at cervical and lumbar
1/2”
Spinal cord is _ at thoracic
1/4”
