Nervous System 2.2 Module 3 Flashcards
LABEL PLEXUS!
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What do the spinal nerves connect to?
The spinal nerves connect to the spinal cord via roots
Dorsal root?
Sensory
Ventral root?
Motor
FACT list
8 central nerves 12 thoracic nerves 5 lumbar nerves 5 sacral nerves 1 coccygeal nerve
What is a mixed structure?
The mixed refers to a structure having both sensory and motor fibers (the dorsal and ventral roots merge)
what do spinal nerves branch from?
The spinal nerves branch to form dorsal and ventral rami
What is the dorsal rami?
The dorsal rami provide sensory and motor innervations (to supply with nerves) to the skin and smaller back muscles
What is the ventral rami?
The ventral rami provide sensory and motor innervations to the rest of the trunk and larger limbs (FIG)
What is the nerve plexuses formed by?
The nerve plexuses are formed by the ventral rami, the plexuses contain fiber of different spinal nerves, the fibers from each rami project many pathways
What are the overlapping territories?
The overlapping territories means that each muscle receives input from more than 1 spinal nerve (important when spinal nerves are damaged)
what are the four main plexuses?
Cervical, branchial, lumbar and sacral
What is the order?
5 roots (rami), 3 trunks (inf, middle, sup), 3 cords (lateral, posterior and medial) and 5 peripheral nerves
What is the cervical plexus?
located under the sternocleidomastoid, innervates the skin
What is the brachial plexus?
the branchial plexus is located in the neck and innervates the upper limb
What is the lumbar plexus?
Lumbar plexus was located within POSOAS muscle innervates abdominal wall, anterior and medial thigh
What is the sacral plexus?
The sacral plexus is located posterior to lumbar plexus, innervates butt, lower limb and pelvis
What are the 5 important branches?
Axillary, musculocutaneous, median, Ulnar and Radial
What are common brachial plexus injuries?
Injuries to the brachial plexus are common can weaken or paralyse the arm. Like capal tunnel syndrome: the median nerve is compressed (wrist)
Ulnar nerve are vulnerable “funny bone” is superficial
Brachial plexus birth palsy ( difficult delivery leads to the paralysis of the the baby)
What are the different cranial nerves?
12 pairs (sensory, motor and mixed) are arranged along the longitudinal axis of the brain
Steps of cranial nerves?
1) cranial nerve attached to the cerebrum, 2) Cranial attaches to the diencephalon and 3) C.N iii -xiii attaches to brain stem
