WEEK 10/2 > SPINAL CORD Flashcards
SPINAL CORD GENERAL FEATURES
- part of CNS
- Has part of the peripheral nervous system attached to it including most of somatic motor and sensory system
- part of visceral sensory system
- sympathetic part of the visceral motor system
- parasympathetic part of the visceral motor system
LOCATION OF SPINAL CORD
- lies within vertebral canal inside the vertebral column extending from the foramen magnum/C1 rootlets superiorly above LV1 or LV2
WHERE IS THE SPINAL CORD ENLARGED
- in the cervical and lumbosacral region
WHAT IS THE MOST NARROW PART CALLED
- the most narrow part is caudal
called > conus medullaris
WHAT DOES THE SPINAL CORD ATTACH TO
- conus and extending through the lumbar cistern to the lower dura
WHAT IS THE STRAND OF SPINAL CORD IN THE COCYX CALLED
- a strand of pia
- fillum terminalis
WHAT IS LOCATED LATERALLY ALONG THE SPINAL CORD
- subarachnoid spacee
WHAT IS THE SPINAL CORD SURROUNDED WITH
- three meninges
pia > arachnoid > subarachnoid containing CSF
WHAT IS BETWEEN THE OUTER LAYER OF MENINGES AND THE WALL OF VERTEBRAL CANAL
- epidural space which contains veins and adipose tissue
HOW MANY ATTACHMENTS TO THE SPINAL CORD
- 32 pairs of spinal nerves
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 2/3 coccygeal
WHAT IS INCLUDED IN THE PROXIMAL PART OF THE SPINAL CORD NERVES
- dorsal and ventral roots
WHERE DOES THE SPINAL CORD EXIT FROM
- exits the vertebral canal via the intervertebral foramen
ARE THE ROOTS SHORT IN THE CERVICAL VERTEBRAL REGION
yes and horizontal
ARE THE ROOTS LONG AND VERTICAL IN THE SACRAL VERTEBRAL REGIONS
yes
WHAT IS THE COLLECTION OF DORSAL AND VENTRAL ROOTS at the lower term named
CAUDA EQUINA
WHERE DO THE NERVES EXIT FROM IN THE SACRAL REGION
- as anterior and posterior primary ramus through the anterior and posterior sacral foramina
MENINGES
HOW MANY LAYERS IS THE MENINGES COMPOSED OF
three
NAME THE THREE LAYERS OF MENINGES
- deep to superficial
pia > arachnoid > dura
BETWEEN THE ARACHNOID AND PIA IS WHAT
- subarachnoid space which contains CSF
WHERE IS THE CSF FORMED
- within the ventricles of the brain and enters the subarachnoid space via three foramina located beneath the cerebellum
WHERE IS THE CSF FLUID PARTLY RESBORBED
into the venous system via the cerebral venous sinuses
PIA MATER - AHDERES TO
- surface of the spinal cord and with the arachnoid helps form the dentate ligaments
ARACHNOID MATER - ADHERES TO
- to the dura and with the dura extends to about SV2 level
WHAT IS THE ENLARGMENT OF THE ARACHNOID SPACE CALLED
- lumbar cistern
DURA MATER -
- thickest part
- sensory innervation
- lies next to skull
- supports dural venous sinuses S
SOMATIC MOTOR NEURON
- alpha or lower motor neuron
WHAT DO SMN INNERVATE
- skeletal muscle
WHERE ARE THE CELL BODIES OF SMN LOCATED
- ventral horn of the spinal cord > multipolar > dendrites > one branching axon (myelinated)
WHAT DOES SMN ACTIVATE AND CONTACT
- muscle cell membrane at a structure called neuromuscular junction
WHERE IS THE AXON OF SMN LOCATED
- proximally the axon is located in the ventral root
SYMPATHETIC MOTOR NEURON
part of the visceral motor or autonomic nervous system
WHAT DOES SYMPATHETIC MN INNERVATE
- multipolar golgi 1
- smooth muscle and glands
WHERE ARE THE AXONS IN THE SYMPATHETIC MN
- muscular and cutaneous nerves in the limb
WHERE THE POSTGANGLIONIC FIBERS AND WHERE DO THEY JOIN
- join peripheral nerves via gray rami communications and are unmyelinated
WHAT MODALITIES TO SOMATIC SENSORY NEURONS CONVEY
- pain, temperature, touch and proprioception
UNIPOLAR GOLGI 1
- begin peripherally with a free nerve ending
WHERE ARE PERIPHERAL AND CENTRAL PROCESSES WITHIN THE CELL BODY LOCATED
- Dorsal root ganglion
PERIPHERAL NERVE
- schwann cell > endonerium > perineurium > epineuruem
WHAT IS EACH PERIPHERAL NERVE SURROUNDED BY
- myelinated or unmyelinated in a schwann cell
WHAT ARE THE PERIPHERAL NERVE FIBERS SUPPORTING CELLS OF AND HELD TOGETHER BY WHAT
- supporting cells of schwann cells and held together by endoneurieum
WHAT ARE THE FASCICLES IN PERIPHERAL NERVE BOUNDED BY
- connective tissue which contains blood vessels and sometimes adipose tissue > epineureum
SOMATIC SENSORY NEURON CELL BODIES IN THE DRG
- surrounded by satellite cells
WHAT DOES MYELINATION IMPROVE
- action potential conduction velocity
WHAT DOES PERINEUM ACT AS
- blood-pns barrier
