Types of Spina Bifida

Spina Bifida

- Developmental birth defect due to incomplete closure of embryonic neural tube

- Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open.

- If the opening is large enough, this allows a portion of the spinal cord to protrude through the opening in the bones

Spina Bifida Occulta

- Mildest form of SB

- Outer part of some of the vertebrae are not completely closed

- The slit is so small so the spinal cord does not protrude

- Skin at site of lesion may be normal, may have hair growing or may have a dimple

- Most people do not know they have it as it is asymptomatic

- Mostly found out by radiographic imaging of the back

- No relation with back pain

Spina Bifida Cystica

- Cyst protrudes through the defect in the vertebral arch and can result in hydrovephalus and neurological deficits

Meningocele (Posterior)

- Less common form

- Vertebrae develops normally, however the meninges are forced into gaps between the vertebrae

- Nervous system remains undamaged hence unlikely to suffer long-term health problems

- Causes can include a teratoma (encapsulated tumour within tissues/organs resembling normal derivatives of all three germ layers), and other cancers of sacrococcyx, or currarino syndrome (inherited congenital disorder where sacrum is not formed properly and there is a mass in the presacral space in front of sacrum andn there are malformations of the anus)

(Meningomyelocele)

- One of the more severe types of SB where one or more vertebral arches fail to develop completely

- Most common form of SB

- The involved area is represented by a flattened mass of nervous tissue with no overlying membrane hence making baby more prone to life-threatening infections

- Protruded portion of spinal cord and nerves which originate at that level of cord are damaged or not developed properly hence there is a degree of paralysis or loss of sensation below the level of that cord defect

- And hence the higher the level of the lesion, the more severe the nerve dysfunctions and resultant paralysis

- Intense pain can be felt in the lower back and originating down the back knee