Spina bifida (Complete)

Question 1

Define spina bifida

Answer 1

Type of neural tube defect characterised by incomplete closure of spinal column and meninges, resulting in herniation

Question 2

What are the main risk factors for spina bifida?

Answer 2

Inadequate folic acid intake before and during early pregnancy

Maternal diabetes mellitus (poorly controlled).

Maternal obesity

Medications

• Anti-epileptics (e.g. phenytoin, carbamazepine, sodium valproate)

Family History

Question 3

What are the 3 main types of spina bifida?

Answer 3

Spina bifida occulta

• Incomplete formation of spinal vertebrae but no spinal cord herniation

Meningocele

• Incomplete fusion of vertebrae + herniation of meningeal sac

Myelomeningocele

• Incomplete fusion of vertebrae + herniation of meningeal sac + spinal cord

Question 4

Define spina bifida occulta

Answer 4

Incomplete formation of spinal vertebrae but no spinal cord herniation

Question 5

How does spina bifida occulta present clinically?

Answer 5

Asymptomatic

Dimple + patch of hair, or discolouration over the defect

Question 6

Define meningocele

Answer 6

Incomplete fusion of vertebrae + herniation of meningeal sac

Question 7

How does meningocele present clinically?

Answer 7

Visible fluid-filled sac

No neurological abnormalities

Question 8

Define myelomeningocele

Answer 8

Incomplete fusion of vertebrae + herniation of meningeal sac + spinal cord

Question 9

How does myelomeningocele present clinically?

Answer 9

Motor and/or sensory impairment below affected level

Neurogenic bladder and bowel dysfunction

Orthaepaedic abnormalities

• Clubfoot
• Scoliosis

Question 10

How is spina bifida diagnosied typicalled?

Answer 10

Diagnosed via pre-natal scans

Question 11

What pre-natal investigations are used to screen for spina bifida?

Answer 11

Bloods:

Alpha feto-protein (AFP): Elevated in open neural tube defects

Imaging:

Ultrasound: Detect structural abnormalities

Amniocentesis: Elevated acetylcholinesterase confirms diagnosis of open NTD

Question 12

What pre-natal investigations findings are suggestive of spina bifida?

Answer 12

Elevated AFP

Structural abnormalities detected on US

Elevated acetylcholinesterase from amniocentesis

Question 13

What investigation is diagnostic for spina bifida?

Answer 13

Amniocentesis (elevated acetylcholinesterase)

Question 14

What investigations are performed post-natally in spina bifida?

Answer 14

Bedside:

Neurological examination: Check for sensory and motor deficits

Imaging:

CT/MRI: Evaluate extent of disease

Urodynamic studies: Assess bladder function

Question 15

What preventative measures are taken to minimise risk of spina bifida during pregnancy?

Answer 15

Folic acid

• 400 micrograms until 12 weeks gestation in normal pregnancies
• 5mg pre-pregnancy and until 12 weeks in high-risk pregnancies

Question 16

What is the management plan in confirmed cases of spina bifida?

Answer 16

Long-term MDT involvement:

• Paediatricians, neurologists, urologists, physiotherapists

Surgical:

Pre-natal intervensions: In uteru repair of myelomeningocele

Post-natal surgery: Closure within 24-48 hours of birth to prevent further injury and infection

Question 17

What complications are associated with spina bifida?

Answer 17

Neurological complications:

• Hydrocephalus
• Seizures
• Tethered cord syndrome
• Developmental delays

MSK complications:

• Scoliosis
• Contractures
• Hip subluxation (partial dislocation)

Urological:

Chronic urinary retention

Recurrent UTIs

Renal impairment due to bladder dysfunction

Question 18

What differentials should be considered alongside spina bifida?

Answer 18

Tethered cord syndrome

• Progressive motor deficits and bladder dysfunction
• Distinguished by MRI

Saccrococygeal teratoma

• Presents as a sacral mass
• MRI/biopsy shows mixed tissue tumour

Dermal sinus tract

• Connection between skin and spinal tract
• Presents as a dimple
• Distinguished by MRI

Question 19

Dermal sinus tract

Answer 19

Question 20

Saccrococygeal teratoma

Answer 20