Development & Pediatrics:
Neural Tube Defects
Catherine Thompson, PT, PhD, MS
Neural Tube Development
Normal embryologic development
Neural plate  neural tube beings at approximately 18 days
Neural tube closure - cranial end at 24th, caudal end at 26th day
Neural tube defects –
Failure of closure = myelodysplasia = defective development of the spinal cord
Clinical consideration:
Does the mother generally know that she is pregnant when the neural tube is
developing?
At what point could health professionals prevent the development of neural tube
defects?
What might be contributing factors?
TERMINOLOGY
Myelo- = the spinal cord & medulla oblongata
-Dysplasia = abnormal tissue development
Lipo- = fat
-Cele = swelling
Spina = spine
Bifida = split or cleft into two parts
Mening- = membrane
Occulta = closed
Aperta = opened
Types of Myelodysplasia – descriptions below
Spina bifida occulta
Lipomeningocele
Myelocele
Myelomeningocele = Spina Bifida
Spina bifida: midline defect of the bone, skin, spinal column and/or spinal cord
Neurologic Pathology
“Spina bifida occulta”:
A condition involving non-fusion of the halves of the vertebral arches without
disturbance of the underlying neural tissue.
21-26% of parents of children with spina bifida cystica have spina bifida occulta.
Incidence = 4.5-8% in general population.
Complications:
Minimal, if any neuromuscular problems
Increased incidence of urinary tract disorders
May have problems during growth spurts or in adulthood
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“Lipomeningocele”:
Lipoma or fatty tumor located over the lumbosacral spine.
Complications:
Minimal neuromuscular problems
High incidence of bowel and bladder dysfunction resulting
from spinal cord damage at the level of control
“Myelocele”:
Fluid-filled sac with meninges involved but neural tissue unaffected.
Complications:
No evidence of neuromuscular problems.
“Myelomeningocele” or “Spina Bifida”:

a.k.a., spina bifida aperta, spinal bifida cystica, spinal dysraphism,
andmeningomyocele

Meninges and spinal tissue protruding through a dorsal defect in the vertebrae
Complications: See impairments listed below.
Information about Myelomeningocele or Spina Bifida:
Incidence (rate of disease)
Approximately 1/1,000 with 90% survival rate
Prevalence (density of disease)
Higher occurrence in families of Irish and Celtic heritage
Lower occurrence in Japanese
Etiology
Neural tube defects may result from:
A combination of environmental and genetic causes:
 Genetics
Risk for recurrence in siblings is 2-3% in the U.S.
African blacks have the lowest incidence
Celts (East Irish, Western Scots, and all Welsh) have the highest incidence
 Teratogens
valproic acid used to control epilepsy during pregnancy
progeny of “street drug” abusers have increased incidence (drugs vs. nutritional deficit)
 Environmental risks – maternal hyperthermia (hot tubs)
 Nutritional deficiencies - folic acid deficiency, beta carotene deficiency
Interesting note: The link between folic acid deficiency and spina bifida was made
when the incidence of myelomeningocele increased significantly during periods of
drought on the British Isles. Potatoes are high in folic acid and supplementation with
folic acid has decreased the birth incidence of myelomeningocele in this area.
Diagnosis and Detection
Amniocentesis/ blood test (maternal) – Abnormally high levels of alpha-fetoprotein after 14th
week of pregnancy (limitation: problem of false-positive and false-negative results)
Ultrasonography – used to locate site of lesion in back
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Prognosis
Spina bifida is a static and non-progressive defect of the spinal column that is
complicated by 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
Neuromuscular changes below the level of the lesion generally include
abnormal nerve conduction, resulting in:
 Somatosensory losses
 Motor paralysis
 Loss of bowel and bladder control
 Changes in muscle tone
Muscle tone can range from flaccid to normal to spastic including:
 UMN (upper motor neuron) signs with/without true spastic paraparesis
 Progression or changes in neurological function with growth. (See Tethered Cord
Syndrome in the Appendices)
Musculoskeletal 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
 An enlarged head caused by “hydrocephalus”
Both Neurological and Orthopedic: Arnold Chiari Malformation
Arnold Chiari type II Malformation = cerebellar hypoplasia with caudal displacement of the
hindbrain through the foramen magnum
This type of malformation is usually associated with hydrocephalus
Hydrocephalus = excessive amount of cerebrospinal fluid (CSF) in the ventricles of
the brain.
60% of children develop hydrocephalus after surgical closure of their back lesion.
80-90% of children require a CSF shunt to remove fluid from ventricles and relieve pressure
exerted by excessive fluid.
Ventriculoperitoneal (VP) shunt = shunts from lateral ventricle to peritoneum
Clinical consideration: How do you know if the VP shunt is working properly?
Check for early warning signs to prevent potential brain injury from shunt malfunction.
See the Appendices for a list of early warning signs and symptoms.
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Other Health Problems associated with the Arnold Chiari syndrome
Note: These problems can occur at birth or later in life. A severe malformation or changes
during growth can lead to signs and symptoms that can life-threatening, including apnea and
bradycardia.




Cranial Nerve Palsies (IV – oculomotor, IX- glossopharyngeal, and X-vagus).
Pressure from the enlarged ventricles affecting adjacent brain structures, leading to:
Cognitive and perceptual problems
Potential for lower intellect
Memory deficits
Distractibility
“Cocktail party personality” – appears highly verbose & articulated, but uses cliches
& jargon with some inaccurate information given by individual
Visual perceptual deficits
Upper limb coordination/motor control problems: halting and deliberate movement
instead of smooth continuous movement
Spasticity: related to upper motor neuron lesions
Clinical consideration:
At what ages do you think children with spina bifida are at the greatest risk for
neurological changes related to the Arnold Chiari syndrome?
How would you schedule your therapy to ensure that a child with spina bifida could
escape risks associated with progressive neurological dysfunction?
Other Complications Leading to Progressive Neurological Dysfunction
 Syringobulbia (syringes occurring in the brainstem)
 Syringomyelia (syringes anywhere in the spinal cord)
 Hydrocephalus
 Hydromyelia – increased fluid in the central canal of the spinal cord
 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
 Bowel and/or Bladder Dysfunction: potential for neurogenic bowel and/or bladder
(requires clean, intermittent catheterization on a regularly timed schedule)
 Skin Breakdown
 Decubitus ulcers and other types of skin breakdown
 Obesity
 Latex Allergy
Medical Management
 Surgical Closure of back lesion 24-48 hrs after birth
 Surgical alignment of joints and spinal column
 A significant number of children born with club feet due to fetal dyskinesia
 Children with limited trunk control often develop scoliosis.
 Management of bowel and bladder: reduce risks of urinary tract infections
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The Physical Therapist’s Role in Patient/Client Management
(Refer to the Guide to Physical Therapy Practice, APTA July, 1999)
Examination – medical history, review of systems, specific tests and measures for
impairments, functional limitations, and disabilities
Evaluation – Making clinical judgments
Development of a plan to address strengths and limitations
Diagnosis – Develop a PT diagnosis
Prognosis – Habilitation for function, Restoration of function, Compensation for
functional limitations
Intervention –
Interdisciplinary vs. Transdisciplinary
Multi-system – neurological, muscular, skeletal, integumentary,
cardiological, pulmonary, genitourinary, endocrine/metabolic, lymphatic
Multi-settings
Examination of the neonate:
Pre-closure:
 Sensory testing
 Functional muscle testing
 ROM assessment
 Therapeutic positioning for sleeping.
Post-closure:
 Sensory testing
 Functional muscle testing
 Sensory assessment
 Home program instruction
 PROM exercises
 handling and carrying positions
 therapeutic positioning for sleeping).
Overall Goals of Intervention:
Demonstrate optimal alignment of posture for function and mobility
Perform gross motor, fine motor, and oral motor skills that are age-appropriate
Promote independent mobility
Promote independent self-care.
Anticipate and prevent secondary complications
Clinical consideration:
Given the overall goals of intervention listed above, consider which goals could be
accomplished through education or exercise alone, which goals would require
adaptation or compensation for functional limitations, and which goals would require the
purchase of specialized equipment or assistive devises.
Case study:
Sarah was born with a lesion at L4. Her birth weight was 7.2 lb. and she was 48
cm long. On day 1 she had surgery for back closure and had a
ventriculoperitoneal shunt for hydrocephalus placed on day 7. A subsequent
infection required removal and replacement of her shunt. Sarah remained in the
hospital for 2 months.
Clinical consideration: As you reflect on the primary concerns of Sarah across her life
span, consider how you would help Sarah meet her goals for functional independence?
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Primary Concerns for the Newborn with Spina Bifida:
Therapeutic positioning pre- and post-surgery for repair of myelomeningocele.
Case Study:
How would you position Sarah:
a. For the first 24 hours prior to surgery for her back lesion?
b. For the first 2 months following her back surgery?
Primary Concerns for the Young Toddler with Spina Bifida
Developmental delay: delayed and abnormal head and trunk control, righting, and
equilibrium responses
Structural Problems:
Club Foot: a Congenital deformity with the following components: adductus, equinus, varus,
and medial rotation
Case Study:
Sarah has bilateral clubfeet and is not initiating movement to explore her
environment:
How would you facilitate Sarah’s normal motor development?
What might be considered to manage Sarah’s structural problems with her feet.
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Sarah has an L4 lesion. Sarah also has “sloppy knees” from inactive medial
hamstring and quadriceps activity.
What might be considered to help control Sarah’s lower extremity alignment?
(See the following table listing possible orthotic devices:
What type of support does she need for postural control and mobility?
Orthoses and Equipment typical for Children with SB
Consider the physiological costs of mobility when prescribing different types of assistive
devices (Melchert, 1998).
AFO (ankle-foot orthosis
“Our results show that solid AFOs improve prolonged knee extensor activity for barefoot
walking. This is clinically relevant to the gait deterioration and knee pain sometimes seen
in this patient population. We espouse early and persistent orthotic intervention to
reduce compensatory muscular overactivity and maintain gait quality.” (Park, Song,
Vankoski, Moore & Dias, 1997).
Total contact orthosis
A-frame (Toronto standing frame)
Parapodium (Orlau swivel walker)
Star Cart
RGO (new isocentric reciprocal gait orthosis)
FKAFO (Ferrari knee-ankle-foot orthosis
HKAFO (Hip knee-ankle-foot orthosis)
Rollator walker
Floor reaction AFO (a.k.a. anti-crouch orthosis)
Articulating ankle joints in S1-level lesions
Twister cables
Clinical consideration:
Typically children with spina bifida are seen in a transdisciplinary clinic for management
of multiple and varied medical, surgical, and therapeutic needs.
Consider the role of each of the following specialists working with children with spina
bifida:
Neurosurgeon
Orthopedist
Urologist
PT
OT
Speech and language pathologist
Nurse
Psychologist
Social worker
Special educator
Adaptive PE instructor
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Clinical consideration for toddlers:
Encourage brief periods of well-aligned weight-bearing throughout the day to stimulate
acetabular development (reducing the likelihood for hip dysplasia) and to prevent
osteoporosis.
Things to avoid during early childhood:
Avoid infant walkers, jumper seats, swings, bouncer chairs, excessive use of infant car
seats.
Case study:
Sarah is now a 6 year old. She has a neurogenic bladder with recurring urinary
tract infections. Her mother performs intermittent catheterization every 4 hours
and assists with daily bowel movement by performing manual extraction. At age 4
she was walking with bilateral long-leg braces (knees locked) and using forearm
crutches.
What would you do to increase Sarah’s independent motor function?
Successful management is contingent upon early recognition and careful monitoring
(Berbrayer, 1991).
What would you do to prevent secondary complications?
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Case study:
Sarah is now 13 years old. She has had two shunt revisions since her birth, the
most recent being at age 8. She is able to ambulate short distances with her
braces and crutches, but wants to develop a more efficient method to get from
class to class at school and around in the community. Since she is rapidly
outgrowing her orthosis, she would like to eliminate them altogether and use a
wheelchair.
What would you recommend for mobility?
What would you recommend for prevention?
It is normal for children to have problems with body image and self-esteem during
adolescence. How could you help Sarah improve her body image and self-esteem
during these critical years?
During adolescence, several other psychosocial issues become more obvious:
 dependency on parents or caretakers
 poor personal hygiene from lack of independence and motivation,
 need for vocational training
 loss of “cure fantasy” during adolescence
As the physical therapist, how might you manage Sarah’s risk for developing
psychosocial problems?
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Case study: Imagine Sarah at the following ages: 20
30 40
50 60 70
As her consulting physical therapist, what concerns would you have as she ages?
At age 20:
At age 30?
At age 40?
At age 50?
At age 60?
At age 70?
Consider additional roles of the physical therapist for individual’s with
developmental disabilities:
1. Role model for advocacy to improve access to community-based resources.
2. Agent of change to the status quo.
Despite 21st century medicine and treatment advances, many children with spina bifida
never achieve complete independence. Many individuals never marry and never live
away from parents. It is important to note that there is no correlation between level of
independence and level of lesion.
How could you ensure that Sarah develops full independence with minimal functional
limitations and limited disabilities?
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Summary
There are several types of neural tube defects with myelomeningocele or spina bifida being
the most commonly seen by physical therapists.
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.
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
Neurological/integumentary: abnormal or damaged nerve tissue (tethering of spinal cord
with growth),skin breakdown, decubitus ulcers and other types of skin problems
Cardiopulmonary: risk for poor cardiovascular fitness
General health concerns: obesity, latex allergy
Psychosocial problems: diminished self-esteem, poor body image, learned helplessness,
potentially limited social interaction
Resources:
Association for Spina Bifida and Hydrocephalus
http://www.asbah.deomn.co.uk.whatissb.html
Spina Bifida Association
http://www.sbaa.org
Check Internet using the search term: “spina bifida”
References:
Bartonek, A, Saraste, H, Knutson, LM, and Eriksson, M. (1999). Orthotic treatment with
Ferrari knee-ankle-foot orthoses. Pediatric Physical Therapy, 11(1): 33-8.
Bauer, S. (1994) Urologic Care of the Child with Spina Bifida. Spina Bifida Spotlight.
Spina Bifida Association.
Berbrayer, D. (1991). Tethered cord syndrome complicating spina bifida occulta: a case
report. American Journal of Physical Medicine and Rehabilitation, 70(4): 213-4.
Campbell, S. (1994). Myelodysplasia. Physical Therapy for Children. Philadelphia: W.B.
Saunders, p. 571-620.
Karmel-Ross, K, Cooperman, DR, Van Doren, CL. (1992). The effect of electrical
stimulation on quadriceps femoris muscle torque in children with spina bifida.
Physical Therapy. 72 (10): 723-730.
Long, T. and Cintas, H. (1995). Handbook of Pediatric Physical Therapy. Philadelphia:
Williams & Williams.
Melchert, K. (1998). The physiological costs of mobility in children with and without
disabilities. Physical & Occupational Therapy in Pediatrics, 18(2):63-75.
Park, BK, Song, HR, Vankoski, SJ, Moore, CA, Dias, LS. (1997). Gait electromyography
in children with myelomeningocele at the sacral level. Archives of Physical
Medicine and Rehabilitation, 78(5):471-5.
Tecklin, J.S. (1999). Spina Bifida. Pediatric Physical Therapy (2nd Ed). Philadelphia:
J.B. Lippincott.
Williamson, G. (1987). Children with Spina Bifida: Early Intervention and Preschool
Programming. Baltimore: Brookes Publishing.
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APPENDICES:
APPENDIX A: SYMPTOMS OF TETHERED CORD SYNDROME
(Source: http://www.mindspring.com/~borchert/occult.htm)
Note the following symptoms suggest possible tethering cord syndrome. Spinal cord
tethering may result from damage to the spinal nerves during growth spurts or when the
spinal cord develops adhesions to an immovable structure (bone, fat, skin, or other
tissue). Tethering cord syndrome can occur in both spina bifida occulta and spina bifida
aperta.
Lack or reduction of reflexes
Reduced sensations
Numbness, tingling
Spasticity of legs or feet
Rigidity or flaccidity
Foot paralysis
Decreased strength in legs
Muscle atrophy
Brittle bones (osteoporosis)
Abnormal stiffness in gait
Pain or spasms (clonus) in legs or feet
Restless legs during sleep
Development of deformities, esp. clubfoot, plantar flexion limitations,
Clumsiness or balance problems
Loss of bowel and bladder control
Bladder spasms
Lack of sensation and/or control of anal and bladder sphincters
Chronic constipation diarrhea or both
Fecal smearing on underwear
Recurrent urinary tract infections
Curvature of the spine
Sciatica
APPENDIX B: EARLY WARNING SIGNS OF SHUNT DYSFUNCTION
Changes in speech
Fever and malaise
Recurring headache
Decreased activity level
Decreased school performance
Onset of or increased strabismus
Changes in appetite and weight
Incontinence begins or worsens
Onset or worsening of scoliosis
Onset or increased spasticity
Personality change (irritability)
Decreased or static grip strength
Difficult to arouse in the morning
Decreased visuomotor coordination
Decreased visual acuity or diplopia
Decreased visuoperceptual coordination
Onset or increased frequency of seizures
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APPENDIX C: FACTORS TO CONSIDER WHEN EVALUATING BIPED AMBULATION
VERSUS WHEELCHAIR USE OF MOBILITY
The 6 following factors are key:
ENDURANCE – for household needs, for community needs, for recreational needs, for longdistance mobility
EFFICIENCY – walking rate is efficient and adequate for speed to cross intersections and to
meet emergency needs
EFFECTIVENESS – for individual (able to perform transfers, ADLs, w/c maneuvers, carrying
items as needed, reaching needed items, using hands as needed in event or activity)
SAFETY – for the individual (stability and balance, skin integrity), of the environment
(stability, unobstructed, non-slippery, even vs. uneven, congested), of the needed
equipment (durable, adjustable, mobile)
ACCESSIBILITY – access to entrances, to necessary rooms, to adequate position for
participation in activity or event, emergency routes
PREVENTION – adequate weight-bearing to prevent osteoporosis and adequate motor
activity to prevent obesity
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