Neural Tube Defects

Neural Tube Defects

When do neural tube defects occur?

Neural Tube
Development
Normal embryological
development
Neural plate
development -18th day
Cranial closure 24th
day (upper spine)
Caudal closure 26th
day (lower spine)

What is Spina Bifida?
A midline defect of the
bone,
skin,
spinal column, &/or
spinal cord.

Does the
mother
generally
know she is
pregnant
when the
neural tube is
developing?
Clinical Considerations
Note this chart illustrates WEEKS of gestation (pregnancy).

Clinical considerations:
At what point could health professionals prevent
the development of neural tube defects?

Preventive Care
• The United States Public Health Service
recommends that: "All women of
childbearing age in the United States who
are capable of becoming pregnant should
consume 0.4 mg of folic acid per day for the
purpose of reducing their risk of having a
pregnancy affected with spina bifida or other
neural tube defects." Folic acid is a "B"
vitamin that can be found in such foods as:
cereals, broccoli, spinach, corn and others,
and also as a vitamin supplement.

Clinical Considerations
What factors contribute to neural tube defects?

Types of Myelodysplasia*
• Spina bifida occulta
• Lipomeningocele
• Meningocele
• Myelomeningocele = Spina Bifida
*defective development of the spinal cord

Spina bifida occulta
(occulta = closed)
A condition
involving
nonfusion of the
halves of the
vertebral arches
without
disturbance of the
underlying neural
tissue
Neurologic pathology

Lipomeningocele
(lipo = fat)
lipoma or fatty tumor
located over the
lumbosacral spine.
Associated with
bowel & bladder
dysfunction
Neurologic pathology
Lipomeningocele

Neurologic pathology
Meningocele (cele = sac)
Fluid-filled sac with meninges involved but neural
tissue unaffected

Types of Myelodysplasia
Myelomeningocele
or spina bifida:
meninges and spinal
tissue protruding
through a dorsal
defect in the
vertebrae

The spinal defect with
myelomeningocele

• Incidence
– 1/1000
• Prevalence
Incidence and Prevalence
– Increased incidence in families of Celtic and
Irish heritage (genetic or environmental?)
– Increased incidence in minorities (genetic or
environmental?)
– Increased incidence in families

Etiology
Neural Tube defects may result from:
• Combination of environmental and
genetic causes
• Teratogens – Cause developmental
defects
• Nutritional deficiencies - notably, folic
acid deficiency

Diagnosis and Detection
Amniocentesis
AFP - indication of abnormal leakage
Blood test
Maternal blood samples of AFP
Ultrasonography
For locating back lesion vs. cranial signs

Spina bifida is a:
static
Prognosis
non-progressive defect
with worsening from secondary problems.
The prognosis for a normal life span is generally
good for a child with good health habits and a
supportive family/caregiver.

Impairments associated with Spina
Bifida
Physiological changes below the level of the
lesion generally include:
abnormal nerve conduction, resulting in:
somatosensory losses
motor paralysis, including loss of bowel and
bladder control

Impairments associated with Spina
Bifida
Physiological changes below the level of the lesion
generally include:
abnormal nerve conduction, resulting in:
changes in muscle tone*
*Note: Muscle tone can range from flaccid to normal
to spastic; may have UMN signs with/without true
spastic paraparesis; progression of neurologic
dysfunction or change in neurologic status most
concerning

Impairments associated with
Spina Bifida
Anatomical changes below the level of
lesion:
musculoskeletal deformities (scoliosis)
joint and extremity deformities (joint contractures,
club foot, hip subluxations, diminished growth of
non-weight bearing limbs)
osteoporosis
abnormal or damaged nerve tissue

Impairments associated with
Anatomical
changes
associated with a
cervical lesion:
An enlarged head
caused by
hydrocephalus
Spina Bifida
(“water on the
brain” Hydrocephalus

Arnold Chiari Malformation
Arnold Chiari type II
Malformation:
cerebellar hypoplasia
(hypoplasia = reduced
growth)
with caudal displacement
of the hindbrain through
the foramen magnum
usually associated with
hydrocephalus

Health Problems associated with the
Arnold Chiari syndrome
Cranial Nerve Palsies
Visual Deficits
Pressure from the enlarged ventricles
affecting adjacent brain structures
(See Tecklin, page 166, for symptoms
associated with Arnold Chiari syndrome.)

Health Problems associated with the
Arnold Chiari syndrome
Cognitive and perceptual problems:
Potential for lower intellect
Memory deficits
Distractibility
“Cocktail party personality” (chattering
speech - with limited content)
Visual perceptual deficits

Health Problems associated with
Motor dysfunction:
Arnold Chiari syndrome
Upper limb incoordination: halting and
deliberate movement instead of smooth
continuous movement
Spasticity: related to upper motor neuron
lesions

Complications leading to progressive
Tubular cavitation
called a syrinx
neurological dysfunction
• Syringobulbia (syringes occurring in
the brainstem)
• Syringomyelia (syringes anywhere in
the spinal cord)
• Bowel and/or Bladder Dysfunction:
potential for neurogenic bowel and/or
bladder (requires clean, intermittent
catheterization on a regularly timed
schedule)

Hydrocephalus
Hydromyelia
Other Complications
Tethering of the spinal cord: fixation or
tethering of the distal end of the spinal cord
causing intermittent bowstringing of the spinal
cord between the normal cephalic attachment and
the point of tether
Seizures

Related Problems
Skin Breakdown
Decubitus ulcers and other types of
skin breakdown
Obesity
Latex Allergy

• Surgical closure of
back lesion 24-48 hrs
after birth with shunt
insertion within 6
months
Medical Management

Medical Management
• Neurosurgical goals
• Orthopedic goals
• Urologic goals
With the potential of numerous complications in
sight, medical management has a variety of
important goals.
(See Tecklin page 180 for tables listing goals.)

Newborn
Therapeutic positioning pre- and post-surgery for
repair of myelomeningocele.
Keep an eye out for shunt malfunction.

The Young Toddler
Typically seen in a transdisciplinary clinic for
management of multiple and varied medical,
surgical needs, and therapeutic needs.
Transdisciplinary teamwork enhances
communication, prevents delays in care,
coordinates management.
Transdisciplinary team consists of: neurosurgeon,
orthopedist, urologist, PT, OT, nurse, social
worker, and may include others.

Concerns for the Young Toddler
Developmental delay: delayed and
abnormal head and trunk control,
righting, and equilibrium responses
Handling/Positioning: The child needs to
develop upright head control in many
positions

Structural Problems:
• Congenital
deformity with
the following
components:
adductus,
equinus, varus,
and medial
rotation
Club Foot

Structural Problems:
Club Foot
Equinus: due to combination of a plantar-flexed talus,
posterior ankle capsular contracture and shortening of
the gastrocnemius
Varus: frontal plane parallelism of talus and calcaneus,
contracture of the medial subtalar joint capsules and
contracture of the posterior tibialis
Adductus and Medial rotation: metatarsus
adductus, medial deviation of the neck of the talus, and
medial displacement of the talonavicular joint.

Structural Problems
Low Lumbar Paralysis:
“sloppy knees” from
absent lateral
hamstrings (and
active medial
hamstrings and
quads)
Consider the nerves
that innervate these
muscles.

Orthoses and Equipment typical for
• Total contact orthosis
• A-frame (Toronto
standing frame)
• parapodium (Orlau
swivel walker)
• Star Cart
• RGO (new isocentric
RGO)
children with SB
• HKAFO
• rollator walker
• floor reaction AFO
(a.k.a. anti-crouch
orthosis)
• articulating ankle joints
in S1-level lesions
• twister cables

Example of a Parapodium
• Commonly used for
children with high lesions
(T12-L3)
• Offers support to the hips,
knees, and ankles.
• (See Tecklin for additional
descriptions and
illustrations of orthoses
used for various lesion
levels.)

Activities for the Young
Toddler
Stimulate automatic balance responses against
gravity in all positions to activate responses in the
lower extremities.
Encourage brief periods of well-aligned weight-bearing
throughout the day to stimulate acetabular development
(reducing likelihood for hip dysplasia) and prevent
osteoporosis.
Avoid infant walkers, jumper seats, swings, bouncer
chairs, excessive use of infant car seats.

Psychosocial issues:
The Adolescent
• dependency on parents or caretakers
• poor personal hygiene from lack of
independence and motivation,
• need for vocational training
• loss of “cure fantasy” during adolescence

Wheelchair Issues
MY OPINION: I disagree with the statement that
the family should wait until the child is age 5
or 6 to obtain the first wheelchair (p. 181).
Consider the child’s health & quality of life
with and without a wheelchair.
Consult with the family & interdisciplinary team
experts (physicians, Seating Clinic staff, PT
with seating experience,vendors.) before
making wheelchair decisions. Errors are
costly.

The Adult
Need to focus on health promotion and fitness.
Watch for overuse syndrome, especially in
upper extremities. Also, low back pain.
Monitor for safe and properly fitting equipment
(wheelchair, bathroom devices, supportive &
protective shoes
Model advocacy to improve access to
community-based resources.

The Adult
Need to change the status quo:
Despite 21st century medicine and treatment
advances, many children with SB never
achieve independence - many never marry,
never live away from parents. There is not
necessarily a correlation between the level
of independence and level of lesion.

The Challenge
• Look at the case study in your “Neural Tube
Defects” handout. Can you answer the
questions posed for the case presented?
• Contact your instructor for answers to
questions posed in the handout.

Sample Documentation
• Look at the sample documentation of a
case featuring a child with spina bifida.
Can you relate the content of the
medical chart to the development of a
PT diagnosis and appropriate plan of
care? (Give it a try.)

Summary
There are several types of neural tube
defects with myelomeningocele (or
spina bifida) being the most commonly
seen by physical therapists.

Summary
A physical therapist examines the
individual with spina bifida for sensory
and motor deficits as well as perceptual
motor deficits that might result from
brain injury secondary to
hydrocephalus or other neurological
complications.

Summary
Common health problems that require
monitoring include:
• musculoskeletal deformities
(scoliosis), joint and extremity
deformities (joint contractures, club
foot, hip subluxations, diminished
growth of non-weight bearing limbs),
osteoporosis

Summary
Neurological/integumentary
complications: abnormal or
damaged nerve tissue (tethering of
spinal cord with growth),skin
breakdown, decubitus ulcers and
other types of skin problems

Summary
Cardiopulmonary problems: risk for
poor cardiovascular fitness
other health concerns: obesity, latex
allergy
psychosocial problems: diminished
self-esteem, poor body image, learned
helplessness, potentially limited social
interaction

Summary
• The role of the PT in the care of an
individual with spina bifida is to
promote functional independence,
prevent complications, and promote
optimal health across the life span.

Slide 1:
Illustrations
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Slide 5:
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Slide 7:
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Slide 10
Illustrations
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Slide 13:
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Slide 25:
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Slide 29:
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Slide 40:
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