Neural Tube Defects & Spina Bifida Flashcards
what is a neural tube defect
most commonly-occurring complex congenital birth defect associated w long-term survival
what development is occurring at an embryonic level
mass cell division & early differentiation
- ectoderm
- mesoderm
- endoderm
beginnings of heart, CNS, MS system formation
what does the ectoderm develop into
NERVOUS SYSTEM**
skin
teeth
what does the mesoderm develop into
blood vessels
ms
bone
what does the endoderm develop into
GI
GU
non-ms portion of pulm system (ie lungs)
urinary tract
what is the process of ectoderm development into the nervous system
ectoderm ->
neural plate (formed day 18)
** neural tube > CNS
- brain
- SC
** neural crest > PNS
- CNs
- spinal n.
- autonomic n.
- ganglia
when does the neural ectoderm close
26-28days after fertilization
what are the 2 processes after the ectoderm closes
neurulation (cranial)
canalization (caudal)
starts @C1 and proceeds cephalad and caudal directions simultaneously
what are the 2 theories behind path of NTD and what is the flaw
- failure of closure
- rupture of previously closed neural tube
flaw: neither adequately explains all deficits
what are the assumed causes of NTD
genetic vulnerability and/or environmental trigger (ie teratogens, nutritional deficiencies)
what is spinal dysraphism
general term to describe congenital abnormalities that include defects of vertebra, SC, or nerve roots
- many types of NTD/dysraphisms
what is spina bifida occulta
non-fusion vertebral arches
no neural problems
- no change to underlying neural tissues
not visible, it is hidden
where is spina bifida occulta most common
in lumbo and sacral regions
what may be the only evidence of spina bifida occulta
darkened area or pigmentation of skin
what is spina bifida cystica
non-fusion vertebral arches
neural damage
what are 2 types of spina bifida cystica
meningocele
myelomeningocele
what is meningocele
cystic sac w meninges & CSF
SC stays w/i canal but may have abnormalities
what are clinical signs of meningocele
none
- or may have (varied)
what is myelomeningocele
cystic sac like meningocele, but SC and meninges in sac
- could be open
neural tissue - abnormalities
what are the results of myelomeningocele
varying sensory and motor impairment @ level of lesion and below
what is an interchangeable term for meningomyelocele
myelodysplasia
what is the risk w open myelomeningocele
additional damage d/t exposure to amniotic fluid
- high risk for infection and meningitis
what ethnicity is the incidence of spina bifida the highest
hispanic
what are risk factors for spina bifida (8)
- previous NTD-affected pregnancy
- maternal insulin-dependent diabetes
- seizure meds
- medically diagnosed obesity
- maternal hyperthermia
- low folic acid levels
- lower SES
- agent orange
what is a key preventative measure
folic acid
- 400mcg/day preconception up to 3mo of pregnancy
- 4000mcg/day if prior NTD
what do folic acid supplements modify the risk of
modifies inc risk for NTDs for pregnant persons w periconceptual fever
what are 2 clinical presentations of NTDs
- absent sensory/motor below level of lesion (B)
- loss of neural bowel and bladder control
what type of NTDs is absent sensory and motor really common in
myelomeningocele
what are the implications for sensory loss
skin safety and skin care
- teach for inspection
why is ICC important for someone w a loss of neural bowel and bladder control
allows bladder to fully empty and dec risk of infection
for people w a loss of neural bowel and bladder control, what are common intervention/management plans
prophylactics for infection
bowel programs
what does (B) absent sensory and motor below level of lesion look like
may be asymmetrical
may skip levels
may be incomplete/complete
flaccid paralysis unless incomplete -> mix of spasticity & volitional control
what does a loss of neural bowel and bladder control look like
neurogenic w sacral plexus involvement
- neurological control of bladder & sphincters are impaired or absent
what is a red or yellow flag w NTD
new presence of or change in spasticity may be indicative of progressive neurologic dysfunction
what is the PT implication w the possibility of skip lesions in NTDs
PT must test motor function
- left/rest sides
- all myotomes
- all dermatomes
exam must include tests of spasticity and DTRs
what are skip lesions
innervation is intact or partially intact below areas w little to no innervation
what are systems w common complications (3)
CNS
msk
multisystem
what are common CNS complications (3)
- hydrocephalus
- arnold chiari malformation
- progressive neurological dysfunction
- tethered cord syndrome
- hydromyelia
what are 2 examples of multisystem complications
latex allergy
obesity
what is hydrocephalus
abnormal accumulation of CSF in ventricles d/t obstruction
- interrupting CSF circulation
what are sx of hydrocephalus
“sunsetting” of eyes
bulging fontanelle in young infant
VS instability
what is the treatment for hydrocephalus
shunt
- ventriculo-peritoneal (VP)**
—– most common
- ventriculo-atrial (VA)
- ventriculo-pleural
what are reasons for shunt dysfunction
infection
disconnected tubing
tubing needs to be repaired
what are general early warning s/sx of shunt dysfunction (7)
dec activity level
dec school performance
incontinence
visual disturbances
neuro sx (sz, spasticity, arousal, HA)
infection signs (fever, malaise)
speech
what is arnold chiari II malformation (ACMII)
cerebellar hypoplasia
- caudal displacement of cerebellum and medulla thru foramen magnum
severity varies
what are sx of ACMII (7)
stridor
apnea
GE reflux
paralysis of vocal cords
swallowing problems
aspiration (may need tracheostomy)
what is ACMII associated with
hydrocephalus
what is the path of ACMII that is creating the sx seen
impacts the CNs
- think ab bulbar and brainstem functioning and CN compression
what are treatment options for ACMII
manage sx
cervical laminectomy - relieve pressure on SC
what are 3 signs of progressive neurologic dysfunction
- changes in spasticity, strength, sensation, pain
- scoliosis development/worsening
- change in bowel/bladder sphincter control
what are 3 causes for progressive neurologic dysfunction
- tethered cord syndrome
- severe intervertebral disk herniation into spinal canal
- hydromyelia
what is tethered cord syndrome
scarring to SC to overlying dura or skin leading to traction on neural structures
what sx are seen as a result of tethered cord syndrome and why
progressive neurologic changes seen w growth spurts
metabolic changes and ischemia can result from stretching of neural tissues
what is hydromyelia
UE weakness, changes in spasticity d/t altered communication w higher motor centers
what is the intervention for hydromyelia
might put another shunt in
- this time a spinal shunt
what are complications related to CNS dysfunction
- perceptual motor deficits
- communication issues
- developmental delays
- vision (ie strabismus, nystagmus)
how do communication issues related to CNS complications present
early in language development
better expressive than receptive
what is strabismus
problem of control of extraocular eye ms
- eyes do not align w each other when focused on a target
- what is initially received is blurry and confusing
what can cause strabismu
multiple etiologies
- ex: CN damage
what happens if strabismus is untreated
one eye will become more dominant than the other
what is nystagmus
involuntary, uncontrolled repetitive eye movement
- seen in infancy or acquired
what are causes of nystagmus
vestibular main one
- others too
can nystagmus resolve on its oqn
yes - but depends on severity
what nystagmus is the most common
horizontal pendular nystagmus
what can inc nystagmus sx
when one eye is occluded (dec vision)
what is the role of MSK complications like deformities
primary or secondary impairments
what are 5 factors of MSK complications
- ms imbalance
- progressive neurological dysfunction
- intrauterine positioning
- anomalies
- deformities after fx
what are 4 MSK complications seen at LE
- developmental dysplasia of hip
- tibial torsion
- genu varus/valgus
- club feet/foot
what is a consideration when treating someone w LE MSK complications
might not correct bc of neg impact on prolonged immobilization
- depends on pt
what MSK complications are seen at the spine
scoliosis
lumbar kyphosis
what MSK complications are seen at UE and why
overuse syndrome(s)
- depending on motor level, may rely heavily on UE for amb and other functions
what are 4 complications seen at a multisystem level
osteoporosis & osteoporotic fx
skin breakdown
latex allergies
obesity (multifactorial)
what is the PT implication for managing someone w osteoporosis & osteoporotic fx
careful w handling
- short lever arms
what are 3 medical management interventions
prenatal testing: screening & dx
management of neonate
general care guidelines
what are 2 screening tools for prenatal
alphafetoprotein (AFP)
US
what is alphafetoprotein (AFP) and how is it used in prenatal testing
AFP produced by fetal liver, which will go up and travel thru mother’s blood stream
- maternal AFP measured
screening tool
taken b/w 16-18wks (retest prn)
how is US used in prenatal testing
screen/dx tool
screens for abnormalities
how is amniocentesis used in prenatal testing
dx tool
check acetylcholinesterase (more accurate than AFP)
- also check for chromosomal abnormalities
what are medical treatment options if NTD detected prenatally
can treat intra-uterinely or after birth
how is NTD treated intra-uterinely
intra uterine closure of defect
- fix baby and pop back in
- would rather do closer to gestation (20-26wks gestation)
how does intra uterine closure of NTD impact the infant vs mother
infant - reduced complications
- improved function
mother - inc risk of preterm delivery
- thinning of uterus @surgical site
how is detected NTD treated after birth
deliver via C-section (esp if open skin lesion)
- reduces damage to defect
immediate sterile care of lesion
- great risk once exposed to area
surgical closure w/i 24-72hrs
shunt placement prn
what is the goal of SBA care guidelines
EBP guidelines to treat and care for individuals not just conditions associated w SB
what are the 3 key concepts of SBA care guidelines
care coordination
- pt/family centered care w//i medical home
care co-management - team based care in community
considerations
- language
- level of acculturation
- cultural constructs of care
