Class 13 Flashcards
Cervical plexus in the neck:
supplies neck and ______ nerve to the ______
C1 to C5, phrenic, diaphragm
Brachial plexus near the shoulder:
supplies ____ _____ and some of _______ and _____.
______ nerve – carpal tunnel syndrome
C5 to T1, upper limb, shoulder, neck, median
Lumbar plexus in the lower back:
supplies _______ ____, anterior ____ and ______
L1 to L4, abdominal wall, thigh, genitalia
Sacral plexus in the pelvis: ______ and _____
supplies remainder of lower ____ and lower ___
L4, L5, S1 to S4, trunk, limb
Coccygeal plexus:_____ and ___
S4, S5, C0
Sensory (Somatosensory) function:
Proprioception :
carry sensory signals from bones, joints, muscles, and the skin
brain receives information about body position and movements from nerve endings in muscles, tendons, and joints
Motor function – primarily to stimulate ______ ______.
muscle contraction
radial nerve injury:
passes through axilla
crutch paralysis
wrist drop
sciatic nerve injury
sciatica – sharp pain that travels from ____ ____ along the _____ side of the thigh and leg to _____
ninety percent of cases result from herniated _______ ___ or osteoporosis of _____ spine
gluteal region, posterior, ankle
intervertebral disc, lower
Chickenpox
common disease of early childhood
caused by varicella-zoster virus
produces itchy rash that clears up without complications
Varicella-virus remains for life in the ____ _____ ____ and is kept in check by the _____ system
posterior root ganglia, immune
Shingles (herpes zoster) – localized disease caused by the virus traveling down the ____ ____ by fast _____ _____ when immune system is compromised
sensory nerves, axonal transport
Shingles:
common after age of ___
painful trail of skin _______ and fluid-filled vesicles along path of _____
usually in chest and waist on ___ side of the body
pain and _____
childhood ____ ____ vaccinations reduce the risk of shingles later in life
50, discoloration, nerve, one, itching, chicken pox
Dermatome –
a specific area of the skin that receives sensory input from a pair of spinal nerves
Dermatome map –
a diagram of the cutaneous regions innervated by each spinal nerve
Dermatomes overlap their edges as much as ____
- necessary to sever or anesthetize _____ successive spinal nerves to produce a total loss of sensation in one dermatome
50%, three
Pain and/or paresthesia within a dermatome reflects pathology at the involved _____ level!
Ex: Numbness and burning down the C7 dermatome can result from a cervical disc herniation between ___ and ___
spinal, C6 and C7
Dermatomes can be tested for sensitivity using a ______ or ______ object.
Goal is to evaluate changes such as _______ or ________
Reflect nerve root issues in _____.
pinwheel, sharp, numbness, hypersensitivity, spine
Know these dermatomes:
C5, 6, 7, 8
L4, 5, S1
Go look at a map!
Know images of Cervical plexus Brachial plexus Lumbar plexus Sacral plexus Coccygeal plexus
Look at em!
Reflexes:
quick, involuntary, stereotyped reactions of glands or muscle to stimulation
Automatic responses to sensory input that occur without our intent or often even our awareness?
Reflexes
Four important properties of a reflex:
reflexes require stimulation
reflexes are quick (1/50th of a second! – 5-20 milliseconds)
reflexes are involuntary
reflexes are stereotyped
Reflexes include glandular secretion and contraction of ____ ____ types of muscle.
include some _____ responses: ______ reflexes
all three, learned, conditioned
Unlearned skeletal muscle reflexes are mediated by the ______ and _________.
brainstem and spinal cord
Reflexes are _____ – since they involve the _____ _____ _____.
Visceral reflexes deal with the _________.
somatic, somatic nervous system, organs (viscera)
What is the pathway of a reflex arch?
somatic receptors afferent nerve fibers integrating center efferent nerve fibers skeletal muscles
somatic receptors are in:
skin, muscles, or tendons
afferent nerve fibers carry information ____receptors ___ posterior horn of spinal cord or the brainstem.
from, to
the integrating center is a point of synaptic contact between ______ in the gray matter of the spinal cord or brainstem.
-determines whether the ______ neurons issue a signal to the muscles
neurons, efferent
efferent nerve fibers carry motor impulses___ skeletal muscle
to
skeletal muscles: the somatic _______ carry out the response
effectors
Muscle Spindle: ______ receptors (aka _______ fibers) embedded in skeletal muscles.
Stretch, intrafusal
specialized sense organs to monitor the position and movement of the body parts
Proprioceptors
Muscle spindles inform the brain of _____ length and ____ _____.
muscle, body movement
Muscle spindles enable brain to send motor commands back to the muscles that control ______ _____, corrective ______, muscle _____, and ______
coordinated movement, reflexes, tone, posture
when a muscle is stretched, it ‘fights back’ and contracts which maintains increased tonus, making it stiffer than unstretched muscle:
Stretch (myotatic) reflex
Stretch (myotatic) reflex helps maintain _____ and ______
-head starts to tip forward as you fall asleep
muscles _____ to raise the head ie “the nods”
-stabilize joints by balancing tension in _____ and _____ smoothing muscle _____.
equilibrium, posture, contract, extensors, flexors, actions
Stretch reflex is mediated primarily by the _____.
- NOT strictly a _____ reflex
brain, spinal
reflexive contraction of a muscle when its tendon is tapped (the stretched tendon pulls on the muscle!)
Tendon reflex
Examples of a Tendon Reflex:
1. Knee-jerk (patellar) reflex is ______ reflex:
_____ _____ between the afferent and efferent neurons
2. Testing somatic reflexes helps diagnose _____ diseases
monosynaptic, one synapse, many
Reciprocal Inhibition:
- When the agonist is stimulated the antagonist is ______
- Prevents muscles from working _____ each other by _____ the antagonist
- Helpful in _______ to increase range of motion
inhibited, against, inhibiting, rehabilitation
the quick contraction of flexor muscles resulting in the withdrawal of a limb from an injurious stimulus
flexor reflex
The Flexor (Withdrawal) Reflexes: requires contraction of the _____ and relaxation of the ______ in that limb
flexors, extensors
Flexor reflexes have a _______ reflex arc – pathway in which signals travel over _____ _____ on their way back to the muscle
polysynaptic, many synapses
The crossed extension reflex is also known as the ______ reflex arc.
contralateral
the contraction of extensor muscles in the limb opposite of the one that is withdrawn:
crossed extension reflex –(aka contralateral reflex arc)
crossed extension reflex –(aka contralateral reflex arc): maintains balance by extending ____ leg.
other
Tendon organs – _______ in a tendon near its junction with a _____.
Golgi tendon organ - ____ long, nerve fibers entwined in ____ fibers of the tendon
proprioceptors, muscle, 1mm, collagen
The Golgi-Tendon reflex:
Tendon reflex – in response to _____ ____ on the tendon.
-inhibits _____ from contracting strongly
-moderates _____ contraction before it tears a tendon or pulls it loose from the _____ or ____.
excessive tension, muscle, muscle, muscle or bone
