Lecture 21: Spina bifida Flashcards
Spina Bifida - folic acid to prevent
* Neural tube defect (doesnt close at 6 weeks)
* First month after conception-about 28 days gestation (because those first 2 weeks dont really count)
* Defect of variable severity in developing SC
* Umbrella term that includes different types of SC defects
* Occur anywhere along the spine
* Severity depends on size and lcoation of opening in spine and if spinal cord and nerves are ffected - can be so minor nody knows
Myelodysplasia is an alternate umbrella term: - any anomilie of SC or cranium
* anomalies of the SC
* Abnormaltities of the spinal column or cranium
* Arise as a result of an embryonic developmental failure
Spina Bifida Aperta (Cystica)
* Exposed neural tissue visible at birth
* May or may not have a protruding sac at side of lesion
Myelomeningocele:- spinal cord comes out of spinal canal into a sac
* Spinal cord protrudes from spinal canal into a sac
* Defect in lumbosacral area in 85% of cases
* paralysis and loss of sensation below level of defect
* may be boney abnoramlities
notice the boney abrnoamlity below
NOTE: spina bifida is not as clean cut as most. may have some weird sensation below in no real pattern
makes sense why you dont have sensation below this level
Anencephaly = w/o brain (an = w/o) - typically what they have left isnt even brain tissue
* Lethal condition
* Vault of skull usually missing
* Exposed mass of undifferentiated vascular and dyplastic neural tissue
Encephalocele: - instead of having SC coming out its brain coming out of skull (i think)
* most often lethal condition
* Protrustion of brain tissue in a sac typically in occipital area of skull
Different kinds of spina bifida
Spina bifida occulta = only have a tuft of hair ontop of skin
* dont typically find unless you’re having an MRI for something else
* sometimes will have a sacarl demple
Meningocele - things are coming out when they shouldnt
Myelomeningocele - its tottaly open
Spina Bifida Occulta or closed neural tube defect
* Non fusion of vertebral arches
* Incidence: 4.5% of general population
* 21-25% of parents of children with spina bifida (so is genetic)
Closed NTD with Subcutaneous MAss (so they can have a subQ mass)
Lipomyelomeningocele
* fatty subcutaneous mass that passes through the open bifid vertebrae and attaches to the spinal cord
* Varying degrees of lower extremity paralysis, decreased sensation and neurogenic bowel and bladder
* Seldon assocated w/ chiari 2 malformation or hydrocephalus
Meningocele - much less severe
* Skin covered sac filled with cerebral spinal fluid that herniates through vertenral defect with meninges (but the actual spinal cord doesnt and the sac isnt actually open)
* Most often in lumbar or sacral area
* Neurological exam in neonate suually normal
* Neurologic problems may develop with growth
* Hydrocephalus may be associated
* Rarely chiari 2 malformation
Spina bifida - can often see in utero and actually fix while still inside mom
* if they cannot fix it in utero than they don’t want a vaginal birth = more infection (because its litteraly open area that leads to ur brain)
Genetric issues with chromosomes 13,18,21
Teratogens - things that are toxic to the baby
* Excess maternal alc
* Ingestion of drugs valporic acid
* Maternal pre-gestational insulin dependent diabtes
* Maternal pre-gestation obesity
Can be caused by nutritional deficiences (folic acid)
1-10 per 1000 live births worldwide and .2 per 1000 births in USA (becuse we have more folic acid)
Decline in the incidence: increased prenatal screening, improved nutrition for pregant women and folic acid supplementation
Genetic: elevation Irish and Celtic
Low among japanese
Families with 1 child with spina bifida are 3 times more likely to have a second w/ this disorder
Diagnostic infant at birth presence of sac or skin lesion
* Muscle weakness or paralysis below lesion; decreased DTRs
* Sensory impairment below lesion
* Possibility of musculoskeletal deformitties from lack of movement in uteri
* Hip dislocation (unilateral or bilateral)
* Foot deformitites (club foot most common)
* Kyphosis, scoliosis (present in 15-25% of newborns)
* Urinary/bowel dysfunction - if lesion above this lvl
dont need to really know all these for spina bifida - basically if they see anything in the brain / SC on the ultra sound they’re going to look more into it
Cranial Ultrasonographic findings:
* Lemon sign: Overlapping of the frontal bones
* Small cerebellum: Transcerebellar diameter <10 percentile
* Effacement of the cisterna magna: width <2 mm on axial scan of posterior fossa
* Banana sign: small cerebellum hemispheres curling anteiorly and obliteration of the cisterna magna as a result of downward displacement of the hindbrain structures
* Ventriculomegaly: Atrial width: severe > 14mm, borderline: >10 mm
* Funneling of the posterior fossa (Clivus supra occiput angle <72 degrees)
Diagnostic testing for spina bifida
* Prenatal screening during pregancy
* Amniocentesis: Measure for elevated alpha fetoprotein level in the amniotic fluid
* Elevated alpha fetoprotein detect about 89% of neural tube defects
* False negatives and positives
* Prenatal ultrasound of the fetus at 18-20 weeks gestation
* Cranal ultrasongraphy, electromyography, magnetic resonace imaging (MRI)
Prognosis and Sequelae for spina bifida:
* Non progressive following surgical repair - however, we go so it can look like progressive symptoms - fatality = first few weeks or older adult
* Muscukosekeltal deformity, hydrocephalus, potential tethered cord syndrome and other potential secondary problems can cause neurlogical compromise
* Hydrocephalus and arnold chiari 2 malformation: global neurlogic problems (low muscle tone, mild fine motor delays and charcertistic learning disabilities)
* 75% of children with MMC live into their early adult years)
* 85% will attend or gradulate from HS and/or college - so most are very fucntional
* 90% survivial with agrresive tx - close them
* quality of life not signfiicalty impacted - can still function and do what they need to do
Medical / surgical management - we dont do this
* Intravesical botox injevtions
* clean intermittent catheterization and anticholinergic medications for neurogenic bladder - going to have bowel and bladder schedule if they cant go on their own
* seizure medications
* medications for constipation
* neonatal surgery to clsoe nueral tube within 24-48 hours of birth
In utero surgical repair of defect in fetus 20-25 weeks
* significant reverseal of hindbrain herniation
* decreased need for shunting
* improvement in LE function
* decreased physical and chemical damage of exposed neurological tissue of open lesion
will likely have a plathera of providers
check skin
need to be on bowel / bladder shcedule - we dont actually do the management
Prevent msk deofmirty = wolfs law
TESTspina bifida = latex allergies = because they’re sposed to it so often = becomes an allergy same thing w/ CP i think
devices vary depending on level of injury
most energy efficent but needs to be able to do what they need it to do
for when you’re writing these goals
we want indpedence in mobility - we want 1 of our goals to be some kind of functional mobility goal
* even if its C5, make it some kind of bicep flexion or above - maybe indpeendent w/ power mobility etc… - use this for project
say something like “have you had any hospitilizations” that will make these come out quickly
obviously depends on the level of injury
can have deofmrities because they’vehad fx’ over sitting’ msk imbalance, position in utero
* typical below
because their muscles arent working right
spinal fushions to stop those spinal defomrities (muscles not holding them up)
People w/ spina bifida commonly have osteoporosis
* due to limited wt bearing (wolfs law)
11-30% in children have fx
limited wt bearing
proper sitting position is really important - goal = avoid excessive ROM in shoulders