Neurology and Skin

Ascending Tracts
Carry sensory impulses to the brain from receptors of skin, muscle and organs
Lateral Spinothalamic Tract
Pain and Temperature
Posterior Dorsal Column
Touch and Propreoception
Innervation of Spinothalamic Tract
DRG to cross central part of gray and white matter to opposite side of Spinal Cord white matter up tract to Thalamus and to the Primary Sensory Cortex
Location of Sensory Cortex
Posterior central gyrus of parietal lobe
Innervation of Posterior Dorsal Column
DRG and straight up to medulla to the Primary Sensory Cortex
Spinothalamic Tract (contralateral or ipsilateral?)
Posterior Dorsal Column (contralateral or ipsilateral??)
ipsilateral; contralateral in cerebral hemispheres.
Test pain and temperature
Sharp and Dull with cotton tip for pain; hold tube with hot water for temperature.
Lesion on Spinothalamic Tract
Contralateral loss of pain and temperature below level of lesion
Lesion on Dorsal Column Tract
Ipsilateral loss of touch and proprioception below level of lesion
If entire cord damaged, what happens below lesion?
No sensation below lesion; full sensation above the lesion
If only half the cord damaged, what happens below lesion?
Contralateral loss of pain and temperature below the lesion; Ipsilateral depends on which side...
Anterior Horn Cells
Lower Motor Neurons that innervate cervical spine and skeletal muscle
Lateral Corticospinal Tract
Upper Motor Neurons related primarily to the Brain and Spinal Cord.
UMN lesion
spastic paralysis
Motor Cortex location
precentral gyrus of the frontal lobe in each cerebral hemisphere.
LMN lesion
Flaccid paralysis
Etiology of UMN paralysis
Etiology of LMN paralysis
Trauma- gunshot or stab wound
Reflex Arc
involuntary response to stimulus mediated by the spinal cord; not voluntary
Sensory Reflex Pathway
DRG- synapse in SP with motor neurons in anterior root- synapse in SP and back to the same muscle.
Biceps SC location
C5 and C6
Triceps SC location
C6 and C7 and C8
Brachiorradialis SC location
C5 and C6
Patellar SC location
L2 and L3 and L4
Achilles SC location
S1 and S2
Normal Reflex Results
Skeletal muscle contracts when they are stretched by the pull of gravity or external manipulation or when their tendons are stretched.
Set of rhythmic contractions of the same muscle
Hyperactive Reflex
exaggerated reflex seen when monosynaptic reflex arc released
Hyporeflexia sign of
LMN injury-destruction of anterior horn cell
Hyperreflexia sign of
UMN injury- Stroke
Pt feels an object and identifies it
Pt feels letters or numbers written on their skin and identifies it
Pt. is awake and oriented
Pt appears drowsy and may fall asleep if not stimulated
Pt is difficult to arouse from sleep like state; Sleeps most of time; confused when awake
Pt responds only to strong generally painful stimulus; returns to unconscious state when it stops.
Completely unconscious pt - cannot be aroused even by strong painful stimulus
Glasgow Coma Scale
Used for head trauma- Score 3-15, based on Eye opening, Verbal response and Motor response.
Mild Head Trauma
Glasgow Score 14-15; 3% may deteriorate within 48 hours
Moderate Head Trauma
Glasgow Score 9-13; 20% chance of death; 50% chance of long term disability
Severe Head Trauma
Score Less than 9; 40% chance of death in 48 hours
Decorticate posturing
Hands contracted in; Lesion of cerebral cortex
Decerebrate posturing
Hands contracted out; Lesion in brain stem
Brocas aphasia
Can comprehend language, but cannot use motor/speech to get the words out; may have paralysis of upper limb on the right
Wernike's aphasia
unable to comprehend language; speech is used but with wrong words
Charcots Triad
Widening pulse pressure, bradycardia and irregular breathing patterns
Layers of Skin
Epidermis, Dermis and Subcutaneous
Functions of Skin
Protection, Sensory, Temperature, Wound repair, Absorption and Excretion, Production of Vitamin D
Preparation for Skin Assessment
Warm room, good lighting, modesty, use proper equipment, Inspect and Palpate
Inspection of Skin
Look for discoloration, masses, lesions, rashes, bruising (ecchymosis)
Palpation of Skin
Palpate for Edema, Turgor (elasticity), Moisture, Temperature and Texture
Caused by blood flowing out of breaks in vessels
tiny puntate hemorrhages- 1-3 mm round; dark red, purple or brown
Confluent and extensive patch of petechiae and ecchymosis >3 mm flat, red to purple
Causes of Purpuric
Thrombocytopenia and scurvy
Test for Melanoma- Asymmetry, Border Irregularity, Color Variation, Diameter greater than 6 mm, Elevation/Enlargement
Skin Cancer Risk Factors
History, Change in pigmentation or mole, excessive dry or moist, pruritus, bruising, rash or lesion, medications, hair loss
impairment of language modality; Brocas and Wernickes
Brain lesion on the right
contralateral left sided spastic paralysis
Spinal lesion on the right
ipsilateral right sided spastic paralysis
Initial lesion of UMN
spinal shock, pronator weakness followed by spastic paralysis
Spinal cord completed transected
Spastic paralysis below the level of the lesion- on both sides
Anterior Horn cell lesion on right side
Flaccid paralysis on the right side-ipsilaterally- AT THE LEVEL OF THE LESION ONLY
Spinal cord transected also damages Anterior Horn
Spastic paralysis below level of Spinal cord lesion and flaccid paralyis at the level of the anterior horn damaged.
Stroke can damage both
motor and sensory
Dorsal Column Disease
Anterior Horn cell disease
Thumb SC location
Digits 2&3 SC location
Digits 4&5 SC location
Nipple SC location
T4 & T5
Umbilicus SC location
Big Toe SC Location
Middle Toes SC Location
Little Toe SC Location
cutaneous area supplied by the spinal nerve
If patient seems arythmic
use reinforcement technique
Reinforcement Technique
Ask the pt. to perform an isometric exercise in a muscle group away from the one being tested.
Plantar Reflex SC location
L4 to S2
Babinski Reflex sign of
UMN lesion
Paralysis of upper limb on right
sign of Brocas aphasia
progressive deterioration of intellect, behavior and personality due to loss of cortical neurons.
If Brain is deprived of oxygen for 3-5 minutes
Irreversible Brain Damage occurs
bundle of fibers which has the same origin and destination and carries similar impulses.
Kinesthesia- Position Sense
Hold finger and move up, down, left and right; have patient tell which way you are moving it
Position Sense tests the
Posterior Dorsal Column Tract
Romberg Test tests the
Posterior Dorsal Column Tract
Positive Romberg with eyes open and closed
Cerebellar deficit ataxia
Positive Romberg with eyes closed only
Proprioceptive deficit- Sensory ataxia
Two point discrimination
the ability to discriminate whether one or two areas of skin are being stimulated
2-8 mm
40-75 mm
Clumsy movements
uncoordinated unsteady gait
Coordination Equillibrium and Balance