Nerve and Blood Supply of Back Flashcards
what is located in the subdural space?
veins
what is located in the epidural space?
fat
Bell Magendie Law
sensory info goes into spinal cord via dorsal roots of spinal nerves and motor commands leave spinal cord via ventral roots
intermediolateral gray T-T2
preganglionic sympathetic neurons
intermediolateral gray S-S4
preganglionic parasympathetic fibers
spinal nerves are numbered for which vertebrae relative to them?
the vertebrae above, EXCEPT for in the cervical region where, for example, C3 is between C2 and C3. T1 would be between T1 and T2.
what kind of neuron is the dorsal root ganglion?
psuedounipolar
where are the dorsal and spinal roots located?
inside the vertebral canal and join to form spinal nerve
where are the dorsal and spinal rami located?
outside intervertebral foramen and represent bifurcation of spinal nerve
medial branch of dorsal rami
all levels supply muscles, only levels T6 and up are also cutaneous to upper back (sensory to skin)
lateral branch of dorsal rami
all levels supply muscles, only levels T6 and below are also cutaneous to lower back and medial gluteus region
what dorsal rami do not split into medial and lateral branches?
C1, S4/5, Cx1
suboccipital nerve?
dorsal ramus of C1
what is the largest of all dorsal rami?
C2
medial branch of C2 dorsal ramus is also called what?
occipital nerve
where does the lateral branch become cutaneous and medial branch is purely muscular?
T7-12
cervical plexus?
C2-C4, innervates neck, parts of head and shoulders
brachial plexus?
C5-T1, innervates the pectoral girdle and upper limb
lumbosacral plexus
L1-S4, innervates pelvic girdle and lower limb
what is a dermatome?
areas of skin innervated by cutaneous branches of a single spinal nerve
C5-T1 dermatome
upper extremity
C5
thumb
C7
middle finger
C8
pinky
T4
nipple
T10
umbilicus
L1-S2
lower extremity
L1
groin
L4
shin and medial foot
L5
lateral leg and top of foot
S1
pinky toe and bottom of foot
what accompanies the dorsal rami to form the segmentally arranged neurovascular bundles?
small arteries and veins
right side of the heart
receives de-oxygenated blood and sends de-oxygenated blood to the lungs for oxygenation
left side of the heart
receives oxygenated blood from the lungs and returns it to the body
anastomoses
created by the union of blood channels, these may occur at capillary level between arterial and venous systems. arteries to arterioles to capillaries.
collateral circulation
an alternative route of circulation to a body part created by anastomoses of arterial channels. frequent around joints of limbs.
collateral vessels
anastomostic vessels proceeding from superior to inferior
recurrent vessels
anastomostic vessels proceeding from inferior to superior
pulmonary circulation
from right ventricle to the lungs and to the left atrium
systemic circulation
from left ventricle to the body to the right atrium
venous return?
vena cava, hepatic portal system, brachiocephalic veins that form superior vena cava, and azygos system
role of GI tract in lymphatic system?
95% of lymph content drained here. major route of transportation of macromolecules from digestive tract to blood circulatory system
afferent lymph vessels
drain lymph to nodes
efferent lymph vessels
drain lymph from nodes to larger lymph channels
thoracic duct
major lymph channel of body and receives drainage from left side of head and neck, left side of thorax, left arm, abdomen, pelvis and perineum, and both legs
