Spina bifida is a birth defect in which there is incomplete closing of the spine and the membranes around the spinal cord during early development in pregnancy.
This is the mildest form of spina bifida.
In occulta, the outer part of some of the vertebrae is not completely closed.
The splits in the vertebrae are so small that the spinal cord does not protrude.
The skin at the site of the lesion may be normal, or it may have some hair growing from it; there may be a dimple in the skin, or a birthmark.
Many people with this type of spina bifida do not even know they have it, as the condition is asymptomatic in most cases.
About 15% of people have spina bifida occulta, most
people are diagnosed incidentally from spinal X-rays.
A systematic review of radiographic research studies found no relationship between spina bifida occulta and back pain.
However, other studies suggest spina bifida occulta is not always harmless. One study found that among patients with back pain, severity is worse if spina bifida occulta is present. Among females, this could be mistaken for dysmenorrhea.
A posterior meningocele or meningeal cyst is the least common form of spina bifida. In this form, a single developmental defect allows the meninges to herniate between the vertebrae. As the nervous system remains undamaged, individuals with meningocele are unlikely to suffer long-term health problems, although cases of tethered cord have been reported.
teratoma and other tumors of the sacrococcyx and of the presacral space, and Currarino syndrome.
A meningocele may also form through dehiscences in the base of the skull. These may be classified by their
localisation to occipital, frontoethmoidal, or nasal. Endonasal meningoceles lie at the roof of the nasal cavity and may be mistaken for a nasal polyp. They are treated surgically. Encephalomeningoceles are classified in the same way and also contain brain tissue.
Myelomeningocele (MMC), also known as meningomyelocele, is the type of spina bifida that oftenresults in the most severe complications and affects the meninges and nerves.
In individuals with myelomeningocele, the unfused portion of the spinal column allows the spinal cord to protrude through an opening. Myelomeningocele occurs in the third week of embryonic development, during neural tube pore closure. MMC is a failure of this to occur completely.The meningeal membranes that cover the spinal cord also protrude through the opening, forming a sacenclosing the spinal elements, such as meninges, cerebrospinal fluid, and parts of the spinal cord and nerve roots. Myelomeningocele is also associated with Arnold–Chiari malformation, necessitating a VP shunt placement.
Toxins and conditions associated with MMC formation include: calcium-channel blockers, carbamazepine, cytochalasins, hyperthermia, and valproic acid.
Spina bifida with myelocele is the most severe form of myelomeningocele. In this type, the involved area is represented by a flattened, plate-like mass of nervous tissue with no overlying membrane. The exposure of these nerves and tissues make the baby more prone to life-threatening infections such as meningitis.
The protruding portion of the spinal cord and the nerves that originate at that level of the cord are damaged or not properly developed.
As a result there is usually some degree of paralysis and loss of sensation below the level of the spinal cord defect. Thus, the more cranial the level of the defect.
The more severe the associated nerve dysfunction and resultant paralysis may be.
loss of sensation
deformities of the hips,knees or fee
loss of muscle tone.
Spina bifida may cause minimal symptoms or minor physical disabilities. But severe spina bifida can lead to more significant physical disabilities. Severity is affected by:
The size and location of the neural tube defect Whether skin covers the affected area Which spinal nerves come out of the affected area of the spinal cord
This list of possible complications may seem overwhelming, but not all children with spina bifida get all of these complications. And these conditions can be treated.
Walking and mobility problems. The nerves that control the leg muscles don't work properly below the area of the spina bifida defect. This can cause muscle weakness of the legs and sometimes paralysis. Whether a child can walk typically depends on where the defect is, its size, and the care received before and after birth.
Orthopedic complications. Children with myelomeningocele can have a variety of problems in the legs and spine because of weak muscles in the legs and back. The types of problems depend on the location of the defect. Possible problems include orthopedic issues such as:
Curved spine (scoliosis)
Dislocation of the hip
Bone and joint deformities
Bowel and bladder problems. Nerves that supply the bladder and bowels usually don't work properly when children have myelomeningocele. This is because the nerves that supply the bowel and bladder come from the lowest level of the spinal cord.
Accumulation of fluid in the brain (hydrocephalus). Babies born with myelomeningocele commonly experience accumulation of fluid in the brain, a condition known as hydrocephalus.
Shunt malfunction. Shunts placed in the brain to treat hydrocephalus can stop working or become infected. Warning signs may vary. Some of the warning signs of a shunt that isn't working include:
Swelling or redness along the shunt
Changes in the eyes (fixed downward gaze)
Chiari malformation type II. Chiari malformation (kee-AH-ree mal-for-MAY-shun) type II is a common brain abnormality in children with the myelomeningocele type of spina bifida. The brainstem, or lowest part of the brain above the spinal cord, is elongated and positioned lower than usual. This can cause problems with breathing and swallowing. Rarely, compression on this area of the brain occurs and surgery is needed to relieve the pressure.
Infection in the tissues surrounding the brain (meningitis). Some babies with myelomeningocele may develop meningitis, an infection in the tissues surrounding the brain. This potentially life-threatening infection may cause brain injury.
Tethered spinal cord. Tethered spinal cord results when the spinal nerves bind to the scar where the defect was closed surgically. The spinal cord is less able to grow as the child grows. This progressive tethering can cause loss of muscle function to the legs, bowel or bladder. Surgery can limit the degree of disability.
Sleep-disordered breathing. Both children and adults with spina bifida, particularly myelomeningocele, may have sleep apnea or other sleep disorders. Assessment for a sleep disorder in those with myelomeningocele helps detect sleep-disordered breathing, such as sleep apnea, which warrants treatment to improve health and quality of life.
Skin problems. Children with spina bifida may get wounds on their feet, legs, buttocks or back. They can't feel when they get a blister or sore. Sores or blisters can turn into deep wounds or foot infections that are hard to treat. Children with myelomeningocele have a higher risk of wound problems in casts.
Latex allergy. Children with spina bifida have a higher risk of latex allergy, an allergic reaction to natural rubber or latex products. Latex allergy may cause rash, sneezing, itching, watery eyes and a runny nose. It can also cause anaphylaxis,
potentially life-threatening condition in which swelling of the face and airways can make breathing difficult. So it's best to use latex-free gloves and equipment at delivery time and when caring for a child with spina bifida.
Other complications. More problems may arise as children with spina bifida get older, such as urinary tract infections, gastrointestinal (GI) disorders and depression. Children with myelomeningocele may develop learning disabilities, such as problems paying attention, and difficulty learning reading and math.
Folic acid, taken in supplement form starting at least one month before conception and continuing through the first trimester of pregnancy, greatly reduces the risk of spina bifida and other neural tube defects.
Get folic acid first
Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida. Because many women don't discover that they're pregnant until this time, experts recommend that all women of childbearing age take a daily supplement of 400 micrograms (mcg) of folic acid.
Several foods are fortified with 400 mcg of folic acid per serving, including:
Some breakfast cereals
Folic acid may be listed on food packages as folate, which is the natural form of folic acid found in foods.
Adult women who are planning pregnancy or who could become pregnant should be advised to get 400 to 800 mcg of folic acid a day.
Your body doesn't absorb folate as easily as it absorbs synthetic folic acid, and most people don't get the recommended amount of folate through diet alone, so vitamin supplements are necessary to prevent spina bifida. And it's possible that folic acid will also help reduce the risk of other birth defects, including cleft lip, cleft palate and some congenital heart defects.
It's also a good idea to eat a healthy diet, including foods rich in folate or enriched with folic acid. This vitamin is present naturally in many foods, including:
Beans and peas
Citrus fruits and juices
Dark green vegetables, such as broccoli and spinach
When higher doses are needed
If you have spina bifida or if you've previously given birth to a child with spina bifida, you'll need extra folic acid before you become pregnant. If you're taking anti-seizure medications or you have diabetes, you may also benefit from a higher dose of this B vitamin. Check with your doctor before taking additional folic acid supplement.
Three tests can check for spina bifida and other birth defects while the baby is still in the womb:
Blood test: A sample of the mother’s blood is tested to see if it has a certain protein the baby makes called AFP. If the level of AFP is very high, it could mean the baby has spina bifida or another neural tube defect.
Ultrasound: High-frequency sound waves bounce off tissues in your body to make black-and-white pictures of the baby on a computer monitor. If your baby has spina bifida, you may see an open spine or a sac poking out of the spine.
Amniocentesis: If the blood test shows a high level of AFP but the ultrasound looks normal, your doctor may recommend amniocentesis. This is when your doctor uses a needle to take a small amount of fluid from the amniotic sac around the baby. If there’s a high level of AFP in that fluid, that means the skin around the baby's sac is missing and AFP has leaked into the amniotic sac.
Sometimes, spina bifida is diagnosed after a baby is born -- usually if the mother didn’t get prenatal care or the ultrasound didn't show anything wrong.
The doctor probably will want to get X-rays of the baby’s body and do a magnetic resonance imaging (MRI) scan, which uses strong magnets and radio waves to get more detailed images.
Doctors can operate on babies when they’re just a few days old or even while they’re still in the womb. If the baby has meningocele, about 24 to 48 hours after birth, the surgeon will put the membrane around the spinal cord back in place and close the opening.
If the baby has myelomeningocele, the surgeon will put the tissue and spinal cord back inside the baby's body and cover it with skin.
Sometimes the surgeon will also put a hollow tube into the baby’s brain called a shunt to keep water from collecting on the brain (called hydrocephalus). This is also done 24 to 48 hours after the baby’s born.
Surgery sometimes can be done while the baby is still in the womb. Before the 26th week of pregnancy, the surgeon goes into the mother's womb and sews shut the opening over the baby's spinal cord. Children who have this type of surgery seem to have fewer birth defects. But it’s risky to the mother and makes it more likely that the baby will be born too early.
After these surgeries, others may be needed to correct problems with feet, hips, or the spine or to replace the shunt in the brain. Between 20% and 50% of children with myelomeningocele may also have something called progressive tethering, which is when their spinal cords get fastened to the spinal canal. (Normally, the bottom of the spinal cord floats freely in the spinal canal.) As the child grows, the spinal cord stretches, and that causes a loss of muscle and bowel or bladder problems. Surgery may be needed to fix that as well.
Some people with spina bifida need crutches, braces, or wheelchairs to move around, and others need a catheter to help with their bladder issues.
Orthopedic Ambulatory supporting devices
The aim of rehabilitation in patients with SB is to improve the quality of life and independence level of the individuals.
Children with Spina Bifida must achieve their gross motor according to the normal milestone as soon as possible eg sitting ability and crawling.
Children with Spina Bifida must undergo appropriate training eg hydrotherapy, upper and lower body conditioning etc.
Children with Spina Bifida must be trained to be independent in daily activity eg walking training using walking aids or locomotion skills such as advanced wheelchair skills eg wheelie.
Clinical pictures that differ depending on the motor involvement are observed in patients with SB Children with Spina Bifida must be prescribed with joint splint (if necessary) to prevent muscle contracture.
Children with Spina Bifida must be educated to protect their joint to prevent early arthritis caused by overexertion and overuse.
Maximising independence in functional activities such as standing, transferring and walking.
Provision of mobility aids and equipment to increase independence.
Exercises to maintain or improve muscle strength and length.
Anticipating, preventing and minimising secondary effects such as development of contractures.
Positioning and postural advice.
Teaching wheelchair skills to maximise independence.
Provision of appropriate orthotics.
Exercises to improve balance and coordination to prevent risk of falls.