Lecture 1: Neuropathy Flashcards
Brain
Encephalopathy
Spinal Cord
myelopathy
Peripheral nerves
Mononeuropathy : Single nerve
Polyneuropathy : Group of nerves
A spinal nerve consists of?
- roots
- main trunk
- 4 primary branches
- peripheral branches
Roots
- located in the vertebral canal
- are associated with spinal cord though they belong to the peripheral nervous system
Dorsal roots are (sensory/motor) while ventral roots are (sensory/motor)
Dorsal : Sensory-afferent
Ventral: Motor- efferent
Main trunk is located?
intervertebral foramen
Spinal nerve formula is determined by?
total number of vertebrae plus 1
Four primary branches of spinal nerve are?
- Dorsal Primary
- Ventral Primary
- Meningeal
- Communicating
Dorsal Primary Branch
Supplies dorsal axial muscles and skin over the dorsal and dorsolateral body areas
Ventral Primary Branch ***
- Largest primary branch
- Supplies ventral axial (hypaxial muscles), muscles of ventral and ventrolateral regions including thoracic and pelvic limbs including skin over these regions
- ventral branches of lower cervical and thoracic region form the brachial plexus
- ventral branches L4-S4 form the lumbrosacral plexus
Meingeal
supplies the coverings of the spinal cord, blood vessels in the vertebral canal and intervertebral discs
Communicating branch**
Runs from the main trunk of spinal nerve to the sympathetic trunk & chain ganglia
Associated with visceral function
Somatic nerve
associated with the body wall (skin, skeletal muscle, joints, tendons)
Visceral
internal organs, smooth muscle, cardiac muscle, and glands
Functional components of cutaneous nerves
1) somatic afferent : skin & subcutaneous tissue
2) visceral afferent : blood vessels
3) visceral efferent : postganglioic sympathetic fibers
Overlap zone
within the cutaneous area, they are supplied by more than one cutaneous nerve
Autonomous zone
within the cutaneous area, the region that is supplied by only one cutaneous nerve
-use this are to test with hemostat for withdrawal or pain
Dermatomes vs Cutaneous areas
Dermatomes: spinal nerve or spinal segment
Cutaneous areas: individual branches in their territory
Muscle Nerves and their functional components
- somatic afferent
- visceral afferent
- visceral efferent
- somatic efferent- presence of these fibers distinguishes muscle nerves from cutaneous nerves
Can muscle nerves originate from meningeal or communicating branches?
no! only from dorsal or ventral primary branches
