The Spina bifida ( EB ) Is a type of malformation or congenital defect in which the structures associated with the bone marrow Spinal and spinal column does not normally develop in the early stages of gestation (World Health Organization, 2012)
These alterations will cause permanent damages in the spinal cord and in the nervous system that can cause paralysis in the extremities Inferior or different functional alterations (World Health Organization, 2012).
The term Spina bifida Is used to define a great variety of alterations of the development, whose common denominator is a fusion Of the vertebral arches. This malformation can be related both to deficits in the superficial soft tissues and structures Which are located within the spinal canal (Tirapu-Ustarroz et al., 2001).
This pathology is part of the congenital alterations of the neural tube . Specifically, the neural tube is an embryonic structure that during the Gestation is transformed into the brain, spinal cord, and surrounding tissues (Mayo Clinic, 2014).
At a more clinical level, spina bifida is characterized by incomplete formation or defective development at the level of the spinal cord and bones (National Institute of Neurological Disorders and Stroke, 2006).
In addition, in association with spina bifida, it is Hydrocephalus , An alteration that causes an abnormal accumulation of fluid Cerebrospinal fluid in different brain areas and can cause significant Neurological deficits .
There are different forms of spina bifida that vary its range of gravity. When this pathology produces significant alterations, it will be necessary to To use a surgical approach to treat anatomic disorders (Mayo Clinic, 2014).
What is Spina Bifida?
Spina bifida is a type of congenital alteration that is characterized by a development or incomplete formation of different related structures With the brain, the spinal cord waves Meninges (National Institute of Neurological Disorders and Stroke, 2006).
Specifically, spina bifida is one of the Neural tube defects more frequent.
The neural tube is an embryonic structure whose fusion usually takes place around days 18 and 26 of gestation. The caudal area of the neural tube will Place to the spine; The rostral part will form the brain and the cavity will constitute the ventricular system. (Jiménez-León et al., 2013).
In babies with spina bifida, a portion of the neural tube fails to fuse or close properly, causing Spinal cord and bone in the spine (Mayo Clinic, 2014).
Depending on the affected areas, we can distinguish four types of spina bifida: hidden, defects of the closed neural tube, meningocele and Myelomeningocele (National Institute of Neurological Disorders and Stroke, 2006).
About us
In the case of the United States, spina bifida is the most common neural tube defect; Has been estimated to affect approximately 1,500-2,000 children in More than 4,000 live births each year (National Institute of Neurological Disorders and Stroke, 2006).
On the other hand, in Spain, between 8 and 10 children out of 1,000 live births present some type of neural tube abnormality. Specifically, More than half of these are affected by spina bifida (Spina Bifida and Hydrocephalus Spanish Federation of Associations, 2015).
Despite this, in recent years there has been a decline in the incidence of spina bifida due to the use of folic acid In the phase of Pregnancy planning and prevention campaigns targeting health care and users (Spina Bifida and Hydrocephalus Spanish Federation of Associations, 2015).
Types of spina bifida
Most scientific reports distinguish three types of spina bifida: Hidden spina bifida , Meningocele Y Myelomeningocele
Spina bifida oculta
It is the most common and mild form of spina bifida. In this type, structural abnormalities result in a slight separation or gap between One or more bones of the spine (Mayo Clinic, 2014).
It is possible for the hidden spina bifida to produce a malformation of one or more vertebrae. In addition, the hidden attribute implies that the abnormality Is covered by cutaneous tissue (National Institute of Neurological Disorders and Stroke, 2006).
Generally, there is no involvement of the spinal nerves, so that most affected with this type of pathology usually do not show signs and Evident symptoms, so they do not usually experience neurological problems (Mayo Clinic, 2014).
In spite of this, in some cases visible indications of spina bifida in the skin of newborns (Mayo Clinic, 2014) can be observed:
- Accumulation of fat.
- Dimple or birthmark.
- Accumulation of hair.
Approximately 15% of healthy people suffer from hidden spina bifida and do not know it. It is frequently found incidentally in studies of x-rays (Spina Bifida Association, 2015).
Meningocele
It is a rare type of spina bifida, in which the meninges (protective organs that are located, in this case, around the spinal cord, protruyen to Through the vertebral spaces (Mayo Clinic, 2014).
In this case, therefore, the meninges have to protrude from the spinal opening and this malformation may be hidden or exposed (National Institute of Neurological Disorders and Stroke, 2006).
When this occurs, the spinal cord may develop defectively, so it is necessary to remove the membranes through procedures (Mayo Clinic, 2014).
In some cases Meningocele Symptoms may be absent or very mild, while in others paralysis may occur in the limbs, Urinary and / or intestinal dysfunction (National Institute of Neurological Disorders and Stroke, 2006).
Myelomeningocele
He Myelomeningocele Or open spina bifida, is the most serious type. In this alteration, the spinal canal remains open along several segments Spinal, especially in the medial or low back. As a consequence of this Opening, the meninges and the spinal cord, protrude into a sac in the Back (Mayo Clinic, 2014).
In some cases, the skin tissues cover the sac, while in others the tissues and spinal nerves are exposed to the outside Direct (Mayo Clinic, 2014).
This type of pathology seriously threatens the patient's life and also has a significant neurological involvement (Mayo Clinic, 2014):
- Muscle weakness or paralysis in the lower limbs.
- Bowel and bladder problems.
- Convulsive episodes, especially if associated with the development of hydrocephalus.
- Orthopedic alterations (malformations in the feet, imbalance in the hip or scoliosis, among others).
symptom
The presence / absence of symptoms and the severity of their presentation will depend largely on the type of spina bifida that the person suffers.
In cases of hidden spina bifida, it is possible that this alteration occurs asymptomatically, without showing external signs. However, in the Case of Meningocele Physical marks or signs may appear on the skin at the site of the spinal malformation (National Institute of Neurological Disorders and Stroke, 2006).
Generally, it is the Myelomeningocele, the alteration that is going to provoke more signs and symptoms at both the physical and neurological levels. Due to exposure Damage to the spinal cord can cause (NHS, 2015):
- Total or partial paralysis of the legs.
- Inability to walk and adopt different postures.
- Loss of sensation.
- In the skin of the legs and in nearby regions.
- Intestinal and urinary incontinence.
- Development of Hydrocephalus.
- Learning difficulties.
Do people with spina bifida have an intellectual level â?? normal?
Most people with spina bifida have normal intelligence, in line with what is expected for their age and level of development.
However, the development of secondary pathologies such as hydrocephalus can cause damage to the nervous system resulting in different Neuropsychological deficits and learning difficulties.
Hydrocephalus develops when there is an abnormal accumulation of cerebrospinal fluid (CSF) that begin to be stored in the ventricles (Tirapu-Ustarroz et al., 2001). In the present study, it was observed that,
Increased cerebrospinal fluid levels, increased intracranial pressure, and compression of different brain structures To provoke a series of neuropsychological alterations of special importance, especially when the affected ones are in childhood age (Tirapu-Ustarroz et al., 2001).
Neuropsychological alterations may be reflected in:
- Reduction of IQ scores.
- Deficits in motor and tactile skills.
- Visual and spatial processing problems.
- Difficulties in the production of language.
Causes
The specific cause of spina bifida is currently unknown. In spite of this, in the medical and scientific About the parallel contribution of both genetic and environmental factors (Spina Bifida and Hydrocephalus Federación Española de Asociaciones, 2015).
A genetic predisposition has been identified, through which, if there is a family history of neural tube defects or alterations, there is An increased risk of giving birth to a drink with this type of pathology (Spina Bifida and Hydrocephalus Spanish Federation of Associations, 2015).
Risk factor's
Although we do not yet know exactly the causes of spina bifida, some factors have been identified that increase its probability (May Clinic, 2014):
- Sex : A higher prevalence of spina bifida has been identified in the female sex.
- Family background : The parents who have a family history with a history of alterations or defects in the closure of the Neural tube will have a higher probability of having a child with a similar pathology.
- Folate deficiency : Folate is an important substance for the optimal and healthy development of babies during gestation. The Synthetic form found in food and dietary supplements, is called folic acid. A deficit in folic acid levels increases the Risk of neural tube defects.
- Medication : Some antineo-convulsant drugs, such as valproic acid, can cause abnormalities in the closure of the neural tube during Gestation.
- Diabetes : Elevated blood sugar levels that go unchecked can increase the risk of having a baby with Spina bifida.
- Obesity : The disease of obesity before and during pregnancy associates with a high risk of development of this type of Pathologies
Diagnosis
In almost all cases, the presence of spina bifida is diagnosed prenatally. Some of the more commonly used methods alpha analyzes Fetoprotein and fetal ultrasound (National Institute of Neurological Disorders and Stroke, 2006).
However, there are some mild cases that are not detected until the postnatal stage. At this stage, x-ray or neuroimaging techniques may be employed.
Treatment
The type of treatment used in spina bifida depends to a large extent on the type and severity of the disease. Generally, spina bifida does not Requires any type of therapeutic intervention, however, other types do (Mayo Clinic, 2014).
Prenatal surgery
When the presence of an abnormality related to abnormalities in neural tube formation is detected during the embryonic period, Especially spina bifida, various surgical procedures may be employed to treat such defects (Mayo Clinic, 2014).
Specifically, before gestation 26 weeks, it is possible to perform an intrauterine repair of the embryo's spinal cord (Mayo Clinic, 2014).
Many specialists advocate this procedure based on the neurological worsening of babies after birth. So far, fetal surgery Has reported enormous benefits, however, poses some risks for both mother and baby (Mayo Clinic, 2014).
Postnatal surgery
In cases of myelomeningocele, in which there is a high risk of infection, in addition to presenting severe paralysis and serious problems of the Development, early surgery in the spinal cord can enable recovery of functionality and control of progress of deficits (National Institute of Neurological Disorders and Stroke, 2006).
References
- EB. (2015). Spina Bifida . Retrieved from Spina Bifida and Hydrocephalus Spanish Federation of Associations.
- Mayo Clinic. (2014). Diseases and Conditions: Spina bifida . Obtained from Mayo Clinic.
- NHS. (2015). Spina bifida . Obtained from NHS choices.
- NIH. (2014). Spina Bifida . Obtained from MedlinePlus.
- NIH. (2015). Spina Bifida Fact Sheet . Retrieved from the National Institute of Neurological Disorders and Stroke.
- WHO. (2012). Spina bifida and hydrocephalus . Obtained from World Health Organization.
- SBA. (2015). What is SB? Retrieved from"Spina Bifida Association".