MEDICAL FOCUS

SPINA BIFIDA

Written by: MICHELLE L. LANGE, OTR/L, ABDA, ATP/SMS

DEFINITION

Spina bifida is a type of neural tube defect, which is congenital. Theneural tube forms early on in pregnancy, becoming the brain andspinal cord, and typically closes about a month after conception. InSpina bifida, part of this structure does not close, leading to defects inthe spinal cord and the vertebrae in this area. Severity depends on thespecific type of defect, size, location and any associated conditionsand complications.

ETIOLOGY

While no specific cause has been determined, research has indicateda possible combination of genetic, nutritional and environmental riskfactors. This includes a family history of neural tube defects, hot tubuse early in pregnancy and folate (vitamin B9) deficiency.

TYPES

• Spina bifida occulta is a small gap in one or more of thevertebrae. A dimple, hair or birthmark may be present over thisarea. This is the mildest and most common type. No symptomsmay be present.

• Myelomeningocele presents with several vertebrae in the lumbaror thoracic area open and the spinal nerves and meninges movedinto 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 severetype of spina bifida. The sac is reduced surgically.

• Meningocele presents with a sac of fluid at the gap in thevertebrae, however the spinal nerves remain in the spinalcanal and only mild symptoms are present. This is the rarestpresentation. The sac is reduced surgically.

ASSOCIATED CONDITIONS

• Hydrocephalus is a common co-morbidity where cerebral spinalfluid accumulates in the brain. A shunt is placed to reduce thisaccumulation, which can lead to brain damage.

• Many children with myelomeningocele also have a brainabnormality called Chiari malformation where the brainstemis elongated and lower than usual. This can cause issues withbreathing and swallowing. Surgery is sometimes required.

• The spinal nerves may become entrapped in scar tissue fromsurgery to reduce the sac, resulting in a tethered cord. This canoccur during growth, resulting in further loss of function andsometimes requiring surgery.

• Sleep disorders, including sleep apnea, may be present.

• Learning disorders are more common in people with spina bifida.

PATHOPHYSIOLOGY

Issues seen vary with the size and location of thedefect, whether skin covers the sac and which spinalnerves are out of the spinal canal. In general, anythinginnervated below the level of the defect may beimpacted. This can include:

• Walking and mobility issues secondary to paralysisor weakness of the legs

• Orthopedic issues such as spinal curvatures,abnormal growth, poor hip integrity, musclecontractures and changes to bones and joints.

• Bowel and bladder issues

CONTACT THE AUTHOR Michelle may be reached at MICHELLELANGE1@OUTLOOK.COM

REFERENCES1. MAYO CLINIC, PATIENT CARE & HEALTH INFORMATION, DISEASES &CONDITIONS, SPINA BIFIDAHTTPS://WWW.MAYOCLINIC.ORG/DISEASES-CONDITIONS/SPINA-BIFIDA/SYMPTOMS-CAUSES/SYC-20377860#:~:TEXT=SPINA%20BIFIDA%20IS%20A%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.