SC Pathology Flashcards
syndrome
collection of S/S associated with each other, suggest common origin
Myopathy
- disease of motor unit
- weakness, endurance
- tends to be proximal
Muscular Dystrophies
- hereditary myopathy
- progressive weakness, wasting
Myotonic Disorders
- abnormality of fiber membrane
- muscle can’t relax, increased stiffness
- can come from CNS dysfunction
Myasthenia Gravis
- autoimmune – antibodies attack Ach receptors
- affects synapse
- patchy/fluctuating weakness, decreased endurance
- eyes (ptosis)
Chromatolysis
- cell and nucleus swell, nucleus migrates peripherally
- occurs at cell body of injured axon
Wallerian Degeneration
- neurofilaments/axons break up
- myelin broken down, phagocytized
- occurs anterograde to lesion
synaptic stripping
synaptic terminals withdraw from neurons and are replaced by processes of glial cells
Central Lesion (4 factors leading to poor regrowth)
- poor regrowth
- scarce glia
- oligodendrocytes inhibit growth
- no neurolemma sheath
- no trophic factors for regeneration
Peripheral Lesion (4 factors for good regrowth)
- chemotrophic factos secreted by schwann cells attract axons
- adhesive molecules in distal stump promote axon growth
- ihibitory molecules in perineurium prevent regenerating axons from growing astray
- neurolemma sheath
Paralysis/Paresis Defined
decreased voluntary motor unit recruitment
Ipsalateral Segmental Motor Syndrome (lesion to ventral horn)
- paralysis
- hypotonia
- areflexia
- atrophy
- fasiculation, fibrillation
Polio
- LMNL sx (loss of ventral horn)
- normal nerve conduction
- usually follows phase of fever, myalgia (pain and cramping), and malaise
- asymmetrical weakness (focal or unilateral)
- NO sensory loss
Tabes Dorsalis
- syphilis
- S/S indicate marked involvement of dorsal roots, esp. lumbosacral region
- results in degeneration of dorsal columns
- S/S are IPSA and BELOW level of lesion
Tabes Dorsalis – common complaints (4)
- unsteadiness
- sudden lacerating somatic pains
- urinary incontinence
- excruciating abdominal pain
Tabes Dorsalis – neuro exam (5)
- marked impairment of vibration, jt position
- severe deficits in touch/pressure
- ataxic gait
- positive Rhomberg
- Abadie’s sign - no achilles reflex
Brown Sequard Syndrome – ipsa signs (4)
- UMN signs
- loss of kinesthesia and discrim. touch
- LMN signs (segmental)
- autonomic signs
Homer’s syndrome
- associated with Brown Sequard
- ptosis, dry/warm/red face, miosis (contracted pupil)
- due to loss of SNS, PSNS takes over, blood vessels dilate
Brown Sequard – Contra and bilat signs
- Bilat - segmental loss P&T
2. Contra - loss P&T
Anterior White Commissure pathology
- bilateral, segmental loss P&T
* goes up down 1-2 segments – eg) T8-L3 lesion = T10-L5 loss
Syringomyelia – early lesion
- knocks out AWC - crossing fibers of LSTT
- bilateral loss P&T 2 seg below
Amyotrophic Lateral Sclerosis
- affects pyramidal, rubrospinal tracts, AHC, brain stem
- LMN and UMN sx
- cells still alive are hyperreflexive, hypertonic
- NO sensory loss
Primary Lateral Sclerosis
- affects pyramidal tracts only
- only UMN sydrome
Progressive Muscular Atrophy
- AHC only
- LMN only
Progressive Bulbar Palsy
- motor nuclei of BS
- slurred speech, problems swallowing/coughing
- constant danger of aspiration
- C/L regions affected most
Friedrich’s Ataxia
- combined systems disease affecting UMN (motor tracts) and dorsal column, spinocerebellar tracts
- coordination problems, ataxia
- clonus, hypertonia, hyperreflexia
UMNS (5)
IPSA:
- paralysis/paresis
- spasticity
- hyper-reflexia
- clonus
- babinski
LMNS (5)
IPSA:
- paralysis/paresis
- hypotonia
- hypo/areflexia
- fibrillations
- atrophy
Subacute Combined Degeneration
- combined systems disease often seen with pernicious anemia (B12)
- dorsal/lateral funiculi degeneration, esp lumbosacral cord
- distal paresthias, dysesthesia, extremity weakness
- septic paraparesis with ataxia follows
- Lhetmitte’s sign (electric shock upon head flexion)
- difficulty walking
MS
- multiple plaques causing demyelination in CNS
- usu. absent abdominal reflexes due to loss of pyramidals
- bilateral partial paralysis/weakness of LE
- loss of coordination, ataxia
- hyperreflexia (UMN)
Benign MS
- few mild attacks then clearing of sx
- minimal or no disability
- ~20% cases
Relapsing-Remitting MS
- more frequent early attacks with less clearing
- long periods of stability
- some degree of disability
- ~25%
Secondary Chronic Progressive MS
- more attacks, more often with less complete remissions
- may continue to worsen for many years then level off with mod/severe disability
- ~40%
Primary Progressive
- most severe
- severe onset, progressive course without clearing of sx
- least common ~15%
Anterior Spinal Artery Syndrome
- supplied most of ant 2/3 of SC
- abrupt onset S/S
- early LMNL s/s due to spinal shock - impaired bowel/bladder, dissociated sensory loss (P/T)
- followed by UMNL - some develop painful dysesthesia due to sparring of spinoreticulothalamic
- alteration of CNS processing of sensory info due to imbalance caused by intact dorsal column with impaired LSTT
- LMN at level, UMN below level
Traumatic Spinal Cord Injury - early stage
=Spinal Shock
- flaccid, bilat paralysis of ALL ms innervated by segment and all seg below
- loss sensation at level & below
- loss all bladder/bowel
- loss all sexual functions
Traumatic SCI – late stage
- UMNL sx
- loss all sensations at level and below
- automatic reflex neurogenic bladder
- intermittent automatic reflex defecation
- reflex erection, ejaculation
- menstrual irregularites/cessation
Traumatic SCI - autonomic syndromes
=autonomic dysreflexia
- for SCI above T5 (above C4 = death)
- stimulus (bladder/bowel distention) –> sweating, flushing, HTN, headache, reflex bradycardia
- respiratory: decreased vital capacity, decreased response to CO2
Autonomic Respiratory Dystunction Syndrome (SCI)
- due to loss of ascending
- resp arrest or sleep apnea
- hypotension, hyponatremia (low Na), inappropriate ADH secretion, hyperhidrosis
Automatic Bladder
- incontinence, loss of pee control
- bladder empties incompletely due to loss of spinal reflexes that trigger pontine pee center
- bilat SC lesion ABOVE sacral level
Uninhibited Reflex Neurogenic Bladder (UMN type)
- lose voluntary control of filling/emptying
- bladder functions by pontine reflexes only
- normal filling/empyting just no sensation/perception
- bilateral FRONTAL LOBE lesion
Non-Reflexive Bladder
- flaccid wall, incr capacity of bladder
- bladder fills and overflows –> constant dribbling
- pt doesn’t perceive distention
- infection risk
- bilat lesion to SACRAL CORD or PELVIC NERVES
