M EDICA L FOC U S
SPINA BIFIDA
Written by: MICHELLE L. LANGE, OTR/L, ABDA, ATP/SMS
DEFINITION
PATHOPHYSIOLOGY
Spina bifida is a type of neural tube defect, which is congenital. The neural tube forms early on in pregnancy, becoming the brain and spinal cord, and typically closes about a month after conception. In Spina bifida, part of this structure does not close, leading to defects in the spinal cord and the vertebrae in this area. Severity depends on the specific type of defect, size, location and any associated conditions and complications.
Issues seen vary with the size and location of the defect, whether skin covers the sac and which spinal nerves are out of the spinal canal. In general, anything innervated below the level of the defect may be impacted. This can include: • Walking and mobility issues secondary to paralysis or weakness of the legs • Orthopedic issues such as spinal curvatures, abnormal growth, poor hip integrity, muscle contractures and changes to bones and joints. • Bowel and bladder issues
ETIOLOGY While no specific cause has been determined, research has indicated a possible combination of genetic, nutritional and environmental risk factors. This includes a family history of neural tube defects, hot tub use early in pregnancy and folate (vitamin B9) deficiency.
TYPES • Spina bifida occulta is a small gap in one or more of the vertebrae. A dimple, hair or birthmark may be present over this area. This is the mildest and most common type. No symptoms may be present. • Myelomeningocele presents with several vertebrae in the lumbar or thoracic area open and the spinal nerves and meninges moved into a sac on the outside of the body. Skin may cover the sac. This can lead to infections and cause paralysis below this level. Bowel and bladder issues are common. This is the most severe type of spina bifida. The sac is reduced surgically. • Meningocele presents with a sac of fluid at the gap in the vertebrae, however the spinal nerves remain in the spinal canal and only mild symptoms are present. This is the rarest presentation. The sac is reduced surgically.
ASSOCIATED CONDITIONS • Hydrocephalus is a common co-morbidity where cerebral spinal fluid accumulates in the brain. A shunt is placed to reduce this accumulation, which can lead to brain damage. • Many children with myelomeningocele also have a brain abnormality called Chiari malformation where the brainstem is elongated and lower than usual. This can cause issues with breathing and swallowing. Surgery is sometimes required. • The spinal nerves may become entrapped in scar tissue from surgery to reduce the sac, resulting in a tethered cord. This can occur during growth, resulting in further loss of function and sometimes requiring surgery. • Sleep disorders, including sleep apnea, may be present. • Learning disorders are more common in people with spina bifida.
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CONTACT THE AUTHOR
Michelle may be reached at MICHELLELANGE1@OUTLOOK.COM REFERENCES 1. MAYO CLINIC, PATIENT CARE & HEALTH INFORMATION, DISEASES & CONDITIONS, SPINA BIFIDA HTTPS://WWW.MAYOCLINIC.ORG/DISEASES-CONDITIONS/SPINA-BIFIDA/ SYMPTOMS-CAUSES/SYC-20377860#:~:TEXT=SPINA%20BIFIDA%20IS%20 A%20BIRTH,THE%20TISSUES%20THAT%20ENCLOSE%20THEM.
Michelle Lange is an occupational therapist with more than 30 years of experience and has been in private practice, Access to Independence, for over 10 years. She is a well-respected lecturer, both nationally and internationally, and has authored numerous texts, chapters and articles. She is the co-editor of Seating and Wheeled Mobility: a clinical resource guide; editor of Fundamentals in Assistive Technology, Fourth Edition, NRRTS Continuing Education Curriculum coordinator and clinical editor of DIRECTIONS magazine. Lange is a RESNA Fellow and member of the Clinician Task Force. Lange is a certified ATP, certified SMS and is a senior disability analyst of the ABDA.
