Spinal cordfunction and dysfunction Flashcards
How many spinal segments are there?
31
How many spinal pairs? What vertebrae types are they?
31 pairs. 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
Where do nerves leave the cord?
Through the intervertebral foramina.
Where are vertebral enlargements for limb innervation located?
Cervical - C3-T1 Lumbar - L1-S3
Are spinal/vertebral levels consistent with one another?
No.
Vertebral cross section. Label meningeal converings.
What is the function of the epidural space?
Space between dura and vertebral periosteum. Fat filled. Venous plexus.
What is the function of arachnoid matter?
Lines the dura.
What is the function of the pia mater?
Adhere tightly to surface of spinal cord.
What is the function of the subarachnoid space?
CSF filled. Continuous with subarachnoid space of brain.
What is the function of the dura mater?
Form dural sac. Extend to S2. Continuous with innder sheet of dura in cranium.
What is the anterior root?
Carry motor information. Exit spinal cord through anterolateral sulcus.
What is the posterior root?
Carry sensory information. Cell bodies in spinal ganglion. Enters spinal cord at posterolateral sulcus.
What is the spinal ganglion?
Contains cell bodies of sensory afferents. Also pseudounipolar neurons. No synapses.
What is the difference between spinal white an grey matter?
Grey matter - cell bodies
White matter - tracts.
Where can spinal anaesthetic be administered?
Needle into subarachnoid space. Between 3rd and 4th lumbar vertebrae.
Where can epidural anaesthetic be administered?
Into epidural space. Between 4th and 5th lumbar vertebrae.
Define dermatome and myotome.
Dermatome - area of skin innervated by one spinal nerve/spinal segment
Myotome - muscles innervated by one spinal nerve/segment.
Label cross section of spinal cord.
What is the function of the posterior median sulcus?
Divide posterior spinal cord surface into two halves.
What is the function of the anterior median fissure?
Divide the anterior surface of the spinal cord into two halves.
Label diagram to show common nervous roots to and from spinal cord.
What is the difference between a root and a ramus.
Roots contain nerves of only one type (e.g. sensory/motor), ramus contain both.
Label major tracts of the spinal cord.
Understand schematic of corticospinal tract (cortex-spine)
Diagram to show pathway of sensory information from skin to cortex.
Outline the dorsal column pathway. What is conveyed?
Discriminative touch, vibration, proprioception.
Outline the spinothalamic tract pathway. What does it convey?
Pain and temperature.
Where is ANS SNS flow focused?
T1-L2 spinal segments
Where is ANS PNS slow focused?
Brainstem, cranial nerves (III, VII, IX, X).
S2-S4 spinal segments
Name 3 factors determining severity of spinal lesions.
- loss of neural tissue
- vertical level
- transverse plane.
What are the most common causes of spinal injuries?
Road traffic accidents, sports, falls.
Identify the stages of injury to lateral corticospinal tract.
- Stage 1. Spinal shock: loss of reflex activity below the lesion, lasting for days or weeks = flaccid paralysis
- Stage 2. Return of reflexes: hyperreflexia and/or spasticity = rigid paralysis
How is the location of symptoms determined in unilateral lesions?
the relationship of the deficit to the lesion depends on where the tract decussates
Diagram to outline ipselateral/contralateral damage.
Brown-Sequard
