Shubhra Mukherjee, MD

Introduction

Spina Bifida (SB) is a condition that is present at birth, and results from an abnormality in the development of the neural tube, which forms the spinal cord. SB is estimated to be prevalent in 1 out of 1000 births (Shaer et al, 2007). This neural tube defect is more commonly seen among males than females and is caused by genetic and environmental factors, which may include deficiencies in maternal folic acid, selenium, and zinc during the development of the fetus.  Depending on the abnormality, there is weakness in the areas that the damaged nerves control, such as sensory areas and muscles to the abdomen, legs, and bowel and bladder. Most people with SB also have a shunt, to help drain the cerebrospinal fluid out of the brain ventricles. Involvement may be cervical (at the neck), or thoracic (chest), lumbar (low back) or sacral (base of spine).

There are three primary classifications of SB: SB occulta, meningocele, and myelomeningocele (also termed spina bifida cystica or meningomyelocele).

SB occulta encompasses a group of conditions affecting the spinal cord, in which the nerves are usually intact. SB occulta is characterized by an aperture in the spine that is covered by a layer of skin. SB occulta is a mild form of SB that rarely results in disability or symptoms.

Meningocele is characterized by a protruding sack of nerve fluid from the spine. While the nerves are usually intact, an individual with meningocele may possess minor disabilities (similar to neural tube defects).

Myelomeningocele occurs when parts of the spinal cord, combined with innervating nerves, protrude through an opening of the spine. This may result in complete or partial paralysis below the location of the protrusion. This form of SB typically results in nerve damage and other forms of disabilities, making it the most severe form of SB. It is common for spinal fluid draining to be compromised in Myelomeningocele, which may lead to excessive fluid accumulation in the head and cause damage to brain.

Importance of Exercise

Recent advances in surgical treatments and medical care have resulted in greater survival rates and longer lifespans in persons with DMD. As a result, physical impairments and deficiencies in mobility are an issue in this population. Rimmer et al.(2012) have shown that people with disabilities perform less physical activity than their non-disabled peers, which places them at a higher risk for cardiometabolic disease. In addition people with SB have been shown to exhibit higher body mass index (BMI), reduced aerobic capacity, lower functional ambulation, and lower muscular strength compared to people without SB (Luisuwan et al., 2007; Schoenmakers et al., 2009).

Children with SB should engage in holistic physical activity programs at a young age, to enhance the chances of a more physically active lifestyle with aging. Group exercise programs or sports should be encouraged to facilitate psychosocial health. Buffart et al. (2009) have demonstrated that daily physical activity (specifically aerobic exercise) in people with SB was associated with improved quality of life and decreased physical difficulties with activity. The literature involving exercise and people with SB is currently sparse. The exact frequency, intensity, time, and type of exercise for optimal health benefits are still unknown, especially when severity of disability is considered. At a minimum, people with SB should aim to achieve an equal dose of exercise as people who are non-disabled: 150 minutes of moderate-intensity per week, which can be completed in 3-5 days of moderate intensity exercise 30-60 minutes per session (in accordance with American College of Sports Medicine guidelines). An individually tailored exercise program that focuses on a progression of flexibility, strength, and cardiovascular fitness should be incorporated.

Other benefits following exercise may include:

• Prevents deconditioning, and promotes function and endurance
• Helps prevent obesity
• May help improve constipation, resist infection, improve mood, reduce stress, prevent diabetes and atherosclerotic heart disease, and helps lower blood pressure

Important Considerations When Exercising

• Maintain proper posture at all times.
• Many people with spina bifida have latex allergy. If this is the case, always check beforehand to make sure that the exercise equipment is not made of latex. Equipment manufacturers such as Thera-band® offer latex-free versions of their products.
• Incontinence (flaccid or neurogenic bowel/bladder) – Individuals may experience a loss of control with their bowel or bladder. KEY: Monitor urinary cycle, be sure to empty your bowel and bladder before starting exercise.
• If you have a shunt or have had scoliosis surgery, you should discuss exercise activity with your doctor. Avoid excessive trauma to the shunt and tubing.
• Thermoregulation – Irregular body temperatures are often experienced by individuals with SB. KEY: Wear appropriate clothing, drink plenty of fluids and take precautions in certain environments; in warm environments, a fan and water spray will aid in cooling, and in cold environments, wear extra layers.
• Pressure sores (decubitus ulcers) – Damage to the skin or underlying tissue caused by prolonged sitting, using old wheelchair cushions, sitting on hard surfaces, shear forces or as a result of a fall. KEY: Check skin regularly and perform regular wheelchair push-ups, or have the individual reposition him/herself regularly especially when engaged in wheelchair sports. (See strength training section for protocol.)
• Fractures – the bones of the weak limbs may not be as strong as normal (osteoporosis), and can be at risk of breaking with less force than normal. In areas of poor sensation, the only signs of fracture may be redness and swelling of the limb, without pain. If the individual has a concern, have him/her see a doctor.
• Transfers – When applicable, wheelchair users need to know how to transfer him-/herself safely from the wheelchair to an accessible exercise machine. People who provide assistance to wheelchair users should be trained to follow the appropriate guidelines for safe transfers.
• Balance – Use straps or other physical assistance to hold the trunk in position during upright exercise.
• If during exercise, foot and leg swelling occurs, resolve with leg elevation. If swelling is persistent, the individual should discuss this with his/her doctor. Compression stockings may also be helpful to keep swelling down. Monitor skin closely for breakdown in areas of swelling.
• Spasticity – This condition is characterized by high muscle tone and hyperactive stretch reflexes. It typically occurs in the muscles below the site of injury and is aggravate by exposure to cold air, urinary tract infections and physical exercise. KEY: You should stretch spastic muscle groups and avoid exercises that cause excessive spasticity. When you are at home you should extend your legs as often as possible. Discuss ways to reduce muscle spasticity that interferes with activity, with your doctor or physical therapist.

Important Safety Considerations

• Inform your physician that you are starting a regular exercise program.
• Start slowly, beginning with only a few sets and/ or repetitions, or with lesser resistance/ weight. Then gradually build these elements up as you go.
• Warm-up for approximately 10 minutes before starting your exercises, and cool-down after your exercise session.
• Regularly monitor blood pressure, heart rate, and rate of perceived exertion (RPE). (See NCPAD’s General Exercise Guidelines factsheet for more information.)
• Stop exercising if you feel pain or discomfort.
• Don’t exercise if you are ill (i.e., cold, flu, bladder infection, pressure ulcer, unusual spasticity).
• Check medications and their effect on exercise tolerance.
• Extended periods of inactivity may cause osteoporosis.

Cardiovascular Training Guidelines

• Aerobic exercise is important for everyone to maintain cardio-respiratory fitness and endurance.
• The American College of Sports Medicine (ACSM) recommends performing 20 to 60 minutes of continuous aerobic exercise or multiple sessions of short duration (approximately 10 minutes) for three to five sessions per week. For individuals just starting an exercise program, a circuit training program is effective.
• Aerobic exercise can be monitored using an individual’s maximal heart rate (MHR) or rating of perceived exertion (RPE). MHR for individuals with SB may be significantly lower than normal, while RPE should be moderate to somewhat strong. (See NCPAD’s General Exercise Guidelines factsheet for more information.)
• Types of cardiovascular training that benefit individuals with spina bifida are upper-body calisthenics, using the rowing machine, hand cycles and arm ergometers, functional electrical stimulation-leg cycle ergometer (FES-LCE), and adapted sports such as, basketball, track, swimming.

Strength Training Guidelines

• Individuals should strength train all active muscle groups. Start with low weights and gradually build up the program as you get stronger. A fitness trainer may be helpful in setting up a program for you.
• Training sessions should be held three days per week.
• Refrain from training the same muscle groups on consecutive days.
• In order to maintain proper body posture, balance, and equilibrium, wheelchair users need to strengthen the muscles of the shoulder and upper back.
• Upper-body pushing and pressing exercises (bench press, overhead press) will strengthen muscles used for transfers and wheeling, while pulling/rowing exercises will help prevent shoulder overuse injuries and improve sitting posture.
• Perform wheelchair push-ups every 10 to 30 minutes during the day, and hold for 30 to 60 seconds. When doing wheelchair push-ups, be sure to bend the elbows slightly. Lock the wheels and keep anti-tip bars in position. One way to remember this is the “rule” 30 second push-up off the chair every 30 minutes. Some people find it helpful to get a digital watch that beeps every 15 minutes as a reminder.
• For individuals who have movement in their legs, leg exercises can include knee lifts from a sitting position (marching movement), and foot lifts from a sitting position (straightening the knee). Do up to 10 on each side once or twice a day, and add sets of 10 as you gain strength. You can also add ankle weights as your strength improves.
• Use straps or a trained partner for stabilization and balance.
• Vary the type of strengthening exercises to reduce over-use injuries.
• Types of strength training that benefit individuals with spina bifida are free weights, weight machines (Nautilus, for example), medicine ball, wall pulley, and Thera-band®.

Flexibility Training Guidelines

• Flexibility training is important to maintain range of motion in joints, as well as to prevent shoulder injuries in persons who use wheelchairs or crutches.
• Flexibility training also helps to prevent contractures (permanently shortened muscles). Paralyzed muscles should be stretched by a physical therapist, exercise specialist, or by a trained assistant or family member. Muscles that need to be stretched include the hamstrings (the back of the thigh), adductors (inner thigh), muscles that flex the hip, muscles that flex the foot, and muscles that extend the back. Having the individual lie on his/her stomach for rest periods can also help stretch muscles of the hips and back of the thighs.
• Stretches for the muscles of the chest and front of the shoulder are recommended especially for wheelchair users, who tend to have a crouched posture.
• Stretch the shoulders by grasping the elbow with the arm overhead, and pulling back to stretch gently. You can also stretch the front of the shoulder by placing your hand on a wall, fingers pointed backwards with the arm outstretched, and lean forward towards the wall. Hold for one minute each side.
• Stretching the calf muscles helps to decrease swelling, especially if combined with leg massages.
• Types of flexibility training are passive resistance, Thera-band® elastic bands or tubings, standing in a standing frame (if not medically contraindicated), yoga and Pilates.