Residency · Residency · Physical Medicine Rehabilitation
Spina Bifida: Lifelong Physiatric Management
Overview
Most common permanently disabling birth defect: incidence ~3-4 per 10,000 live births (US). Neural tube defect resulting from failure of neural tube closure during weeks 3-4 of embryogenesis. Folic acid supplementation (400 mcg/day preconception) reduces incidence by 50-70%. Physiatrist is central coordinator of lifelong multidisciplinary care. Life expectancy has improved dramatically (>85% survive to adulthood with modern care).
Types of Spina Bifida
Spina Bifida Occulta
Incomplete vertebral arch closure without meningeal or neural herniation. Often asymptomatic, incidental finding (5-10% of population). May be associated with cutaneous markers: hairy patch, dimple, lipoma, hemangioma. Rarely causes neurological deficits unless associated with tethered cord.
Meningocele
Meninges herniate through vertebral defect, CSF-filled sac. Neural elements remain within spinal canal. Better prognosis; minimal neurological deficit in most cases. Surgical repair required.
Myelomeningocele (MMC)
Most common and severe form. Spinal cord and nerve roots herniate through defect. Open neural placode exposed or covered by thin membrane. Associated with Chiari II malformation and hydrocephalus (85-90%).
Most commonly lumbosacral (75%). Requires surgical closure within 24-72 hours of birth. Prenatal repair (MOMS trial): improved motor outcomes and reduced shunt rates.
<image>Types of spina bifida showing cross-sectional anatomy of spina bifida occulta, meningocele, and myelomeningocele</image>
Motor Level and Functional Outcomes
Motor Level Determination
Lowest functional motor level (voluntary antigravity strength). Determines ambulatory potential, orthotic needs, and independence.
Thoracic Level
No lower extremity voluntary movement. Wheelchair-dependent for mobility. RGOs (reciprocating gait orthoses) or HKAFOs for therapeutic standing/limited ambulation (high energy cost). Household ambulation may be possible in young children but rarely sustained into adulthood. Upper extremity function preserved.
High Lumbar (L1-L2)
Hip flexion present (iliopsoas). Wheelchair primary mobility. KAFOs for therapeutic/household ambulation. Most transition to full-time wheelchair use by adolescence.
Mid-Lumbar (L3-L4)
Knee extension (quadriceps) present. L3: community ambulation possible with KAFOs and forearm crutches. L4: ankle dorsiflexion present, AFOs may suffice. Community ambulation achieved by most in childhood; many transition to wheelchair for long distances by adulthood.
Low Lumbar (L5)
Ankle dorsiflexion and hip abduction present. Weak plantarflexion. Community ambulation with AFOs. Most maintain ambulation into adulthood.
Sacral Level
Near-normal lower extremity strength. Community ambulation without assistive devices. May have foot deformities, weakness of intrinsic foot muscles. Neurogenic bladder/bowel still present.
| Motor Level | Key Muscles Present | Orthotic Needs | Ambulatory Potential |
|---|---|---|---|
| Thoracic | None in LE | RGO/HKAFO (therapeutic) | Wheelchair-dependent |
| L1-L2 | Hip flexion (iliopsoas) | KAFOs | Wheelchair primary; therapeutic ambulation |
| L3-L4 | Knee extension (quads) | KAFOs → AFOs | Community ambulation; many transition to wheelchair |
| L5 | Ankle dorsiflexion, hip abduction | AFOs | Community ambulation maintained |
| Sacral | Near-normal LE strength | None or shoe inserts | Independent community ambulation |
Neurogenic Bladder Management
Pathophysiology
Lower motor neuron bladder (areflexic detrusor) typical in MMC. Variable sphincter function. High risk for upper tract damage if not managed properly.
Management
Clean intermittent catheterization (CIC): mainstay, typically started at birth. Anticholinergics: oxybutynin to increase bladder capacity and reduce detrusor pressure. Urodynamics: baseline by 1 year, then annual or as clinically indicated. Goal: detrusor pressure < 40 cmH2O.
Renal ultrasound: annual surveillance for hydronephrosis. Augmentation cystoplasty: if medical management fails to protect upper tracts. Continent catheterizable channel (Mitrofanoff): appendicovesicostomy for independent catheterization when urethral access is difficult. Continence: achievable in 80-90% with comprehensive program.
UTI Management
Asymptomatic bacteriuria: DO NOT treat (universal with CIC). Symptomatic UTI: fever, malaise, foul urine, increased incontinence. Prophylactic antibiotics: controversial, generally not recommended. Adequate fluid intake and consistent catheterization schedule.
Neurogenic Bowel Management
Decreased rectal sensation and sphincter control. Constipation is most common problem. Bowel program components: High-fiber diet and adequate fluids.
Timed bowel program (after meals, using gastrocolic reflex). Digital stimulation or suppositories (glycerin, bisacodyl). Oral laxatives if needed (polyethylene glycol). Malone antegrade continence enema (MACE/ACE): appendicostomy for antegrade colonic washout. High satisfaction rates. Social continence achieved in 70-80%. Transanal irrigation systems: alternative to MACE.
<image>Bladder and bowel management algorithm for myelomeningocele by age group</image>
Chiari II Malformation and Hydrocephalus
Chiari II Malformation
Present in nearly all MMC patients. Cerebellar tonsils and brainstem herniate through foramen magnum. May cause: stridor, swallowing difficulties, apnea (brainstem compression), upper extremity weakness, nystagmus. Symptomatic in 15-35%. Surgical decompression for symptomatic cases.
Hydrocephalus
85-90% of MMC patients develop hydrocephalus. VP shunt placed in ~80%. Shunt malfunction: the most important emergency in spina bifida. Signs: headache, vomiting, irritability, lethargy, change in mental status, bulging fontanelle (infants).
Can be life-threatening - requires urgent evaluation. Shunt series (radiographs) and CT head. Average patient will have 2-3 shunt revisions during childhood. Endoscopic third ventriculostomy (ETV): alternative to shunt in selected patients.
Tethered Cord
Progressive neurological deterioration from spinal cord fixation at surgery site. Incidence of symptomatic tethering: 20-50%. Signs: change in motor function, progressive scoliosis, new pain, deteriorating bladder function, orthopedic foot deformity changes. Diagnosis: MRI (cord tethering is universal radiographically - clinical correlation essential). Surgical untethering when symptomatic.
Skin and Pressure Injury Prevention
Insensate skin below motor level. Pressure injury risk from braces, wheelchair, immobility. Education: skin checks, weight shifts, proper-fitting orthotics. Latex allergy: 30-60% sensitization rate.
Latex-free precautions for all medical encounters from birth. High-risk for anaphylaxis. Avoid latex gloves, catheters, balloons.
Obesity and Metabolic Health
Obesity prevalence: 40-50% of MMC patients. Contributing factors: decreased mobility, low lean body mass, low metabolic rate. Standard BMI calculations overestimate height-based norms (short stature, kyphosis). Body composition assessment preferred (DEXA, skinfold measurements). Aggressive dietary management and adapted physical activity.
Orthopedic Issues
Scoliosis: 50-90% prevalence, often progressive (especially congenital vertebral anomalies). Bracing: limited effectiveness in neuromuscular scoliosis. Surgical fusion for progressive curves (>40-50 degrees). Hip dysplasia/dislocation: common at L3-L4 level (muscle imbalance).
Surgical reduction controversial (does not improve ambulation). Foot deformities: clubfoot, vertical talus, cavovarus. Serial casting, surgical correction as needed. Must ensure insensate feet are protected from skin breakdown in orthotics. Fractures: osteoporotic bones in paralyzed limbs. May present as painless swelling (insensate limbs).
Cognitive and Learning
Average IQ is lower than population norms (mean ~80 in MMC with shunted hydrocephalus). Specific learning profile: good verbal skills but impaired nonverbal/executive function. "Cocktail party speech": superficially articulate but lacking depth. Executive function deficits: planning, organization, problem-solving. Attention difficulties common. Neuropsychological assessment recommended for school placement.
Transition to Adult Care
Begin planning at age 14-16. Key transition domains: Self-care independence (CIC, bowel program, skin checks). Medical self-management (understanding medications, appointments).
Vocational/educational planning. Sexuality and reproductive health counseling. Independent living and transportation. Financial literacy and benefits management.
Guardianship/conservatorship if cognitively impaired. Adult spina bifida clinics remain limited in availability. Adult physiatrist should assume ongoing coordinating role.
<image>Lifelong surveillance and management timeline for myelomeningocele from birth through adulthood</image>
Clinical Pearls
The motor level is the most important predictor of ambulatory function - L4 and below generally maintain community ambulation into adulthood; L3 and above increasingly rely on wheelchairs. Shunt malfunction is the most dangerous acute complication - any acute change in mental status, headache, or vomiting warrants urgent evaluation with CT head and shunt series. Latex allergy affects 30-60% of spina bifida patients - all medical environments should use latex-free precautions from birth. Neurogenic bladder management with CIC and urodynamic monitoring has transformed survival by preventing renal failure, which was historically the leading cause of death. Symptomatic tethered cord should be suspected when there is ANY new neurological change (motor, sensory, bowel, bladder, orthopedic deformity) - MRI alone is insufficient because radiographic tethering is universal.
References
- Adzick NS, et al. A randomized trial of prenatal versus postnatal repair of myelomeningocele (MOMS trial). N Engl J Med. 2011;364(11):993-1004.
- Liptak GS, et al. Evidence-based practice guideline summary: health supervision for children with spina bifida. J Pediatr Rehabil Med. 2020;13(4):535-543.
- Oakeshott P, et al. Long-term outcome in open spina bifida. Dev Med Child Neurol. 2010;52(8):794-795.
- Bowman RM, et al. Spina bifida outcome: a 25-year prospective. Pediatr Neurosurg. 2001;34(3):114-120.
- Cifu DX, et al. Braddom's Physical Medicine and Rehabilitation. 6th ed. Elsevier; 2020.
