Spina Bifida Flashcards
What is Spina Bifida?
Defective development of any part of the spinal cord
commonly lower cord
What are the different names for spina bifida?
● Neural tube defect ● Meningomyelocele ● Myelomenigecele ● Myelodysplasia ● Spina Bifida
What is the etiology of spina bifida?
● No definitive cause defined
● Genetics
- associated with chromosomal aberrations
- recurrent risk for siblings is 2-3%
- Irish/Celtic origin
● Teratogens (including prescription meds)
- excess maternal alcohol intake
- use of valproic acid (anticonvulsant)
● Nutritional Deficits
-Folic acid deficiency - supplementation has resulted in a decreased
● Environmental
-Increased internal body temperature
What occurs during embryology 17-19 days?
neural plate formation
● brain and spinal cord are exposed
● occurs between 17-23 days
What occurs during embryology 19-21 days post conception?
Neural fold formation
Forms CNS
What occurs during embryology 22-23 days post conception?
Fusion of the neural folds
What occurs during embryology 23-26 days post conception?
Rosteral (toward the head) closure occurs
Anencephaly
What occurs during embryology 26-30 days post conception?
Caudal closure occurs
Myelomeningocele
What is the difference between a normal fetus and one with spina bifida? When does the change occur?
Normally, neural tube closes at 28 days after
fertilization.
Spina Bifida: failure of neural tube to close properly
How is spina bifida diagnosed?
- Ultrasound
- Protein screening (blood test-acetylcholine esterase)
- Amniotic fluid analysis/amniocentesis (high AFP)
What is the incidence of spina bifida?
1/1000 births in the US
***unless you’re celtic or irish, then it could be 1/80
What is spina bifida aperta?
One or many malformed vertebrae may allow
tissue to protrude from spinal canal and form a sac (may also be referred to as Spina Bifida Cystica)
Where does spina bifida aperta most commonly occur?
Lumbar
What are the types of spina bifida aperta?
Meningocele and Myelomeningocele
What is spina bifida occulta?
non-fusion of the vertebral arches, no
disturbance of underlying neural tissue
What are the characteristics of spina bifida occulta?
● Lipoma of the spinal cord, most are visible
● May be large/small, subcutaneous masses of fat
● Most commonly in lumbar or sacral spine
● Usually no neurologic or orthopedic problems
● High association with mild urinary tract disorders
What is spina bifida aperta Meningocele?
● skin covered
● contains only meninges, does not contain functional nerve tissue
● Not as serious
● Not as common as
myelomeningocele
● Often seen with teratomas, tumors of the sacrococcyx and presacral space, and Currarino Syndrome
What is spina bifida aperta Myelomeningocele?
● open spinal cord defect, with meninges and spinal cord protruding through vertebral defect
● not skin covered
(membrane covered)
● usually associated with spinal nerve paralysis (below the level of the
defect)
What is hydrocephalus?
● Due to ventricular obstruction or overproduction of CSF
● 25% or more with
myelomeningocele are born
with hydrocephalus
● An additional 60% develop
hydrocephalus after surgery
● Hydrocephalus impacting on
motor cortex or pyramidal tracts
● Diminished upper limb
coordination is common
● 80-90% with hydrocephalus will require a VP shunt
● Arnold-Chiari type II malformation (extension of both cerebellar and brain stem tissue into the foramen magnum) may result in caudal displacement of the hindbrain through the foramen
magnum (obstructive)
–The cerebellum is now placing pressure on the brainstem and
spinal cord
Arnold-Chiari type II malformation (extension of both cerebellar and brain stem tissue into the foramen magnum) may result in:
caudal displacement of the hindbrain through the foramen magnum (obstructive)
—The cerebellum is now placing pressure on the brainstem and
spinal cord
What are the associated conditions with spina bifida?
Hydrocephalus
Meningitis
UTI and kidney infections
Ischemia and cord tethering
Sensory deficits
Decubiti
Cognitive dysfunction
Progressive neurological dysfunction
Seizures
_______% of children with myelomeningocele
develop voluntary control of urinary or anal sphincter
(______ innervation)
Fewer than 5%
S2-S4 innervation
What is sun setting of the eyes?
See more sclera of the eye
Which musculoskeletal deformities are associated with spina bifida?
Congenital scoliosis
Club foot deformity
What causes musculoskeletal deformities in children with spina bifida?
● neurologic dysfunction ● intrauterine positioning ● coexisting congenital malformations
● arthrogryposis
● habitually assumed postures after birth
● decreased AROM
What are the typical postural problems in children with spina bifida?
forward head, rounded shoulders, kyphosis, scoliosis, excessive lordosis, anterior pelvic tilt, rotational deformities of the hip or tibia, flexed hips, knees, pronated feet
What is the association between scoliosis and spina bifida?
● more frequently observed in higher level lesions, increases in severity with age
● orthotic treatment of scoliosis common, to prevent further progression
● possible surgical fusion
● restrictive lung disease frequent infections
True or false: Be aggressive in stretching children with spina bifida
True
_______ level lesions (___-___) have unopposed flex + add which often leads to subluxation/dislocation
High level (L1-L2)
True or false: There is no change in the knees of children with spina bifida
False. Contractures decrease in severity then increase
Ankle and foot pathologies are most common with spina bifida to levels ________.
L5 and above
What are the foot and ankle pathologies associated with spina bifida?
● equinovarus deformity (talipes equinus) ● forefoot varus or valgus ● forefoot supination or pronation ● calcaneal varus or valgus ● pes cavus and planus ● claw toe deformity
What is used to assess functional motor levels in spina bifida?
IMSG (International Myelodysplasia Study Group)
With spina bifida, the motor level is defined as …
the lowest intact functional neuromuscular segment.
What are the types of lesions of spina bifida?
● complete transection- flaccid, absent reflexes
● incomplete lesion-spasticity, hyper-reflexia, possibly
altered voluntary control
● skip lesions- isolate function below apparent level of
the lesion.
