Introduction

One of the most common birth defects in the United States is spina bifida, which is a neural tube defect that occurs in the first month of pregnancy. It occurs when part of the fetus’ spine fails to close properly and the child may be born with a partially exposed spine. The prevalence of spina bifida has decreased in recent years, yet there are approximately 18 cases per 100,000 live births. The risk decreases with the second or third child. 

There are 3 types of spina bifida:¹ 

Occulta

Represents approximately 12% of cases and is the less severe form, often called ‘hidden spina bifida’. This is due to the spinal cord and nerves being relatively normal with no opening on the back, and little disturbance to the individual’s normal functioning.

Meningocele

This form of spina bifida occurs when the bones surrounding the spinal cord do not close, thus pushing the meninges outwards and forming a fluid-filled sac. Meninges are the three layers surrounding the brain and spinal cord, which function as a protective layer. Meningocele is the rarest form of spina bifida and very little impairment occurs as the spinal cord and nerves are not severely affected.

Myelomeningocele

The most common form of spina bifida, occurring in about 75% of cases. It is the most severe form, resulting in the most impairments. In this form spinal cord protrusion through the back occurs and sometimes tissues and nerves may be exposed.

The location and severity of the spinal cord defect correlates with the neurological disabilities experienced. If the lower portion of the spinal cord is exposed there may only be bladder and bowel dysfunction. However, the more severe cases present with similar issues accompanied by total paralysis of the legs.

Importance of bladder control

A neurogenic bladder is commonly found in children with spina bifida, where the spinal cord nerves controlling the bladder have not formed properly. There are problems with bladder function and urination, including urine storage and bladder emptying. 

Since this condition is detected in early pregnancy and/or at birth, a neurosurgeon will often perform surgery to repair and close the defect within 48 hours of delivery. Other management strategies include clean intermittent catheterisation, or treatment with an anticholinergic medication.

Clean intermittent catheterisation is done to protect the kidneys and prevent urinary tract infection (UTI), and allows the child to wear underwear. Anticholinergic medication is prescribed to relax the bladder and improve urine storage, whilst also helping to protect the kidneys. Bladder augmentation is another treatment option, which increases bladder size.² 

Causes and risk factors

Spina bifida is caused by the spinal column being split (bifid) in early embryo development, due to the neural tube closing improperly or failing to close. While the exact cause of this is uncertain, there are many contributing factors for general neural tube defects, which spina bifida falls under:³

• Maternal nutrition: alcohol use, caffeine use, low folate intake, low dietary quality, elevated glycaemic load/index, low methionine and serum choline intake/levels, and low serum vitamin B12 and C levels, amongst others
• Maternal factors: smoking, hyperthermia (high body temperature), low socio-economic status, pre-gestational insulin-dependent diabetes and obesity, maternal infections, psychosocial stress, and valproic acid use 
• Environmental factors: ambient air pollution, disinfectant-polluted drinking water, indoor air pollution, nitrate-related products, organic solvents, pesticides, and polycyclic aromatic hydrocarbons

Impact of spina bifida on bladder control

Due to the nerves between the brain, bowel, and bladder being damaged, an individual with spina bifida has little control over their bladder. There may be a complete loss of sensation in the bladder area or the sphincter muscles may not work properly. This is the reason why it is important to maintain proper bladder and bowel health.⁴ 

Management and treatment options

Clean intermittent catheterisation (CIC) 

CIC is the primary method of treatment and improves bladder function. The process involves placing a small flexible tube inside the bladder, which drains the urine manually. The process only takes as long as it does to urinate. Some children may be unable to self-catheterise through the urethra.

In those instances, a catheterisable stoma will be inserted. This is a surgical opening in the side of the abdomen or in the belly button that allows children and teenagers to handle catheterisation independently. CIC is done every day, as often as the person needs to urinate. 

Gloves are not necessary but hand washing is important to prevent infection. Catheters are easy to dispose of but some must be washed properly and placed on a paper towel to dry. Public washrooms are not an appropriate place to leave them, but a nurse’s office would be with approval.⁵

CICs help avoid the complications of neuropathic bladder dysfunction and if a physician determines a child to be at risk for upper tract changes, they may recommend night-time continuous catheterisation.⁶ 

Anticholinergics 

Anticholinergic medications block the activity of the neurotransmitter acetylcholine. This means the “rest and digest” function of the parasympathetic system, by which the involuntary actions of the smooth muscle lining the urinary tract are controlled, is blocked. Oxybutynin and tolterodine are the most common anticholinergics prescribed to treat bladder incontinence from spina bifida.

Many anticholinergics are taken as oral drugs, some may be administered intravenously (through the veins), and others may be administered intranasally (via the nose). Oxybutynin and tolterodine are often administered orally. However, there are negative side effects from these drugs which are listed below:⁶

• General: hyperthermia and anhidrosis
• Cardiovascular: tachycardia, flushing, and arrhythmias
• Gastrointestinal: reduced gut motility, constipation, vomiting, reduced saliva, and tear production
• Genitourinary: urinary retention
• Head, eyes, ears, nose and throat (HEENT): blurred vision, mydriasis (dilated pupils), narrow-angle glaucoma, and potentially vision loss
• Skin: inhibition of sweating
• Musculoskeletal: diminished muscle contraction

Lifestyle considerations

Physical activity

While maintaining a healthy and physically active lifestyle is important for everyone, it is particularly important for individuals with spina bifida. Losing strength and function is one of the side effects of leading a sedentary lifestyle.

In cases of individuals with spina bifida, this means a loss of their independence in carrying out daily activities. While physical activity improves overall abilities, it also improves mental health, cognitive functioning and mood, all of which are key in managing spina bifida. Children under 17 years old and over 6 years old are advised the following:⁷

• Minimum 60 minutes of physical activity per day
• Within this physical activity, the majority should be aerobic exercise and vigorous, intense, aerobic exercise should be done a minimum of three times/days a week 
• Muscle strengthening exercises should also be incorporated into a minimum of three days/times a week. This can be included within the 60 minutes or more per day 
• Bone strengthening activities should also be done at least three times a week as part of the 60 minutes or more. This one often gets overlooked or forgotten 

The guidelines for adults are slightly different: 

• Inactivity should be avoided as much as possible. Even participating in a little physical activity routinely provides health benefits 
• For substantial results, or optimal health, 150 minutes a week of moderate-intensity exercise is recommended. This can be reduced to 75 minutes a week of vigorous-intensity aerobic physical activity. Alternatively, a combination, or modification, of these two are also acceptable. If performing aerobic exercise, it should be performed in a period of 10 minutes and for the most optimal effects, should be spread throughout the week 
• If an adult wishes to seek more extensive health benefits, they should increase aerobic physical activity to 300 minutes a week of moderate intensity, or 150 minutes a week of vigorous intensity aerobic physical activity. Alternatively, a combination of the two will also work. If physical activity beyond this amount is conducted, then further health benefits may be seen 
• Muscle strength training should also be incorporated into the weekly routine, at least two or three times. And this should ideally involve all major muscle groups

Bladder training techniques

This fact sheet from the Spina Bifida Association provides toilet training techniques for young children. It suggests that a catheterisation program is not necessary and that parents must be particularly patient with children with spina bifida, as their milestones may be delayed.

It also touches upon bowel training by supplementing the child’s diet with fruit, fruit juices, fibre and other recommendations. They suggest rectal stimulants as well for certain cases which aim to reduce constipation. 

Bowel and bladder issues are often discussed together, as bowel function precedes bladder function. The fact sheet mentions some common indicators for poorer bladder control: a child who leaks urine constantly, never produces a good urinary stream, or does not indicate an urge to urinate even when the bladder is full. This should not, however, deter the parent from trying to achieve toilet training.

Training the bladder in a child with Spina Bifida is not immensely different than training any other child. It helps to place the child on the toilet immediately after waking and at regular intervals, such as every two hours, to establish a routine. This may result in an increase in dryness at first. Lastly, rewards and other incentives may help establish bladder control.

Summary

Overall, a child with spina bifida should not be treated very differently from other children. They are able to live fully functioning and relatively normal lives despite their condition. Children should be supported at all stages and should be encouraged with positive reinforcement during the toilet training period.