Spinal Neurology Flashcards
Cell body of a neuron
Soma
Extends from the body of a neuron. Receives signal information from the local environment. Associated with receptors that are designed to sense specific stimuli or react to specific chemical transmitters.
Dendrite
Signals which travel as action potentials are generated here.
Axon
Summation of signals received from dendrites, which can either be stimulatory or inhibitory.
Action Potential
When the Action Potential reaches the end of the axon it causes the release of a _____.
Neurotransmitter
Action potentials speed are based on what two factors?
Diameter & Degree of Myelination
Produces myelin in the CNS
Oligodendrocytes
Demyelinization of the CNS
Multiple Sclerosis (MS)
Insulate nerve fibers
Produces myelin in the PNS
Schwann Cells
Demyelinization of the PNS
Guillain-Barre
Cell bodies are located in the _____.
DRG
Each DRG neuron contains a peripheral process, which extends to the periphery along the path taken by the spinal nerve and it’s branches, and a central process, which extends into the CNS as the _____ of the spinal nerve.
Dorsal Root
Sensory neurons for touch, hearing
Mechanoreceptors
Sensory neurons for temperature
Thermoreceptors
Sensory neurons for pain
Nocioceptors
Sensory neurons for smell, taste
Chemoreceptors
Sensory neurons for vision
Electromagnetic
These afferent neurons innervate and activate skeletal muscle fibers through the Myoneural junction.
Large diameter, Fast Conducting
Acetylcholine (NT)
Found in the Muscle Spindles & supply proprioceptive information regarding “Rate of Change”
Alpha Motor Neurons (1A)
These efferent neurons innervate muscle spindles & establish a set point for muscle tone
Gamma Motor Neurons (A gamma)
Touch Pressure Receptor Afferent neurons
Detect tension on tendon or joint
Sensory for joint position sense, vibration sense, and two-point discrimination
Found in Golgi Tendon Organ
A beta Neurons (1B)
Type of nerve fiber that detects Fast Pain (pressure pain)
ie: Pinch
A delta (III)
Preganglionic Autonomic Efferent neurons
White Rami Communicantes
B nerve fibers
Type of nerve fiber that detects Slow Pain
Temperature Afferent
Postganglionic Autonomic Efferent
Gray Rami Communicantes
C nerve fibers
Un-myelinated pain fibers
Small diameter
Slow conductivity
Substance P is NT
C nerve fibers (IV)
What is the most important function of the Autonomic Nervous System?
Regulate Blood Flow
What is the location of the Sympathetics; what is it’s response; and what is the NT?
T1 - L2: Lateral Horn of the spinal cord
Fight or Flight response
Adrenergic (Epinephrine)
What is the location of the Parasympathetics; what is it’s response; and what is the NT?
Cranio-sacral division: CN III, VII, IX, X & Sacral Nerves 2-4
“Rest & Digest” - urination, defecation, eating & sex
Cholinergic (Acetylcholine)
What body responses are seen with sympathetic response?
- Skin Vasoconstriction
- Increased sudomotor activity
- Pupil Dilation
- Bronchodilation
- Tachycardia
- Blood to large muscles
- Pilomotor response
What body responses are seen with parasympathetic response?
- Increased peristalsis
- Increased smooth muscle activity
- Depressed respiration
- Pupil constriction
- Bradycardia
- Bowel & Bladder active
- Stimulation of secretions
If sympathetics are stimulated/facilitated:
Sympathicotonia
If parasympathetics are stimulated/facilitated:
Parasympathicotonia / Vagotonia
If sympathetics or parasympathetics are inhibited:
Atonia
Motor tracts/Descending Tracts:
Proximal muscle flexors of UE
Rubrospinal
Motor tracts/Descending Tracts:
Extensor muscles of back and arms, except any back muscle innervated by a plexus (ie: Dorsal scapular, Rhomboids, Levator Scapula, Thoracodorsal, Latissimus dorsi)
Reticulospinal
Motor tracts/Descending Tracts:
Neck muscles & reflex to light
Tectospinal
Motor tracts/Descending Tracts:
from Cerebellum & Vestibular Nuclei
Extensor muscles of back & legs
Vestibulospinal
Motor tracts/Descending Tracts:
for Flexors of distal extremities (hands and feet)
Corticospinal
Reflex to light
Superior Colliculus (Tectospinal)
Reflex to sound
Inferior Colliculus (Tectospinal)
Lateral Spinothalamic tract detects…
Pain & Temperature
Ventral Spinothalamic tract detects…
Crude touch & pressure
What tract carries conscious proprioception (vibration, joint position sense, and 2-point discrimination)
Dorsal Columns Medial Lemniscus (DCML)
What are the receptors in the DCML for:
- Touch?
- Vibration?
- Joint position sense?
Touch - Meissner’s / Merkel’s
Vibration - Pacinian
Joint Position Sense - Ruffini
What tract carries unconscious proprioception
Spinocerebellar pathways
Spinocerebellar pathways detect what?
Stretch - Muscle Spindle - type 1a fibers
Tension - Golgi Tendon - type 1b fibers
Goals of the Adjustment:
- Stimulate the 1b Golgi Tendons & postsynaptic inhibition of the alpha motor neurons which innervate skeletal muscle due to the fast stretch on the tendon.
- Close the pain gate by sending a proprioceptive message to the CNS on large type A fibers
- Increase mechanoreceptor bombardment thereby closing the pain gate
- Break up adhesions
- Increase mobility/motion
- Improve neurological function
FYI
MERIC CHART:
Global functions systemic effect
C1
MERIC CHART:
- Tonsils
- Heart & Lung
- Gallbladder
- Stomach
- Liver, Pancreas, Gallbladder
- Kidney
- Ovary, Colon (sympathetically driven)
- Colon, Uterus (parasympathetically driven)
Tonsils: C2/3 Heart & Lung: T1-T4 Gallbladder: T4 Stomach: T5-T9 Liver, Pancreas, Gallbladder: T6-T10 Kidney: T10-T12 Ovary, Colon: L1-L2 Colon, Uterus: Sacrum
