Prognosis ...
What Does it Mean? What Are We to Expect?

Researchers have identified the SMN1 gene as the primary manufacturer of the SMN Protein. It is the absence/defect of this SMN1 gene that causes Spinal Muscular Atrophy. However, there is another form of this gene called SMN2. The SMN2 gene is similar to SMN1, but does not produce as much protein, or the right kind of protein, as the SMN1 gene. One determination of prognosis is the number of copies of the SMN2 gene. The greater the number of SMN2 copies, the more SMN protein is produced and the greater likelihood that more motor neurons remain healthy and productive. Individuals with only 1 or 2 copies of the SMN2 gene will typically have the most severe expressions of SMA. Three or more copies of the SMN2 gene will typically mean a less severe expression.

Each type of SMA has variability among individual patients. Please keep this in mind when considering an individual’s care.

Raising a child with SMA should be no different than raising a child who is not affected. Do as many things as possible that are age appropriate. Many times this means making adaptations. It is very important that children with SMA are assisted in reaching their utmost potential.

It is important to understand that parents and patients have rights and that you are not alone. Most hospitals have social service departments that can give you a shoulder to lean on. Don't be afraid to say NO if something doesn't seem right. Don't be intimidated or afraid to ask questions. If you forget to ask something, call your doctor or contact Families of SMA for suggestions. In this context, it is also important that your child be followed by a physician who is familiar with SMA and its complications.

SPINAL MASCULAR ATROPHY - Type I (and some Type II)

While most children diagnosed with Type I are still infants there are a myriad of things that can be done to assist in the cognitive, physical and emotional health of your child. Using balloons and feathers as toys makes for wonderful stimulation and allows them a feeling of independence and accomplishment. Reaching games are a form of physical or occupational therapy that can be very helpful. Instructions in range of motion and other physical/occupational therapy ideas by a licensed therapist are important no matter how young the child. Your physical/occupational therapist can also suggest ideal seating systems that will be most helpful in the comfort and maximum mobility of your child.

Water therapy can be very helpful as the buoyancy of the water allows movement of the arms and legs that may otherwise not be there. Be sure that the water temperature is at least 90°F and that the child’s head does not go under the water or into the water. You must watch so that the child has no possibility of aspirating (getting fluid into their lungs).

Children with SMA who have difficulty swallowing are at risk for aspirating when eating. Sometimes the child may aspirate his/her own secretions. The child may choke while eating and may also experience weight loss as swallowing becomes more difficult. Assistive feeding may be necessary. Two possible options are:

  1. Nasogatric Tube (NG-Tube): a surgically placed tube through the nose that goes directly into the stomach.
  2. Gastrostomy Tube (G-Tube): a surgically placed tube through the skin that goes directly into the stomach.

Because a child with SMA Type I has difficulty coughing, contacting a respiratory therapist is very important so you can be instructed in chest physiotherapy (CPT). CPT is a method of clearing the lungs of accumulated mucus by using positioning and clapping on the chest to assist in loosening secretions. Saliva can settle in the nasopharynx causing a faint gurgling sound. Often the secretions or mucus need to be removed by the use of a suction machine. Blowing raspberries and bubbles encourages respiratory strength.

Individuals with SMA can also benefit from the use of a cough assist machine. The Cough Assist™ achieves this by applying a positive pressure to the airways to inflate the lungs, and then rapidly shifts to negative pressure to pull the air out of the lungs. The rapid shift in pressure produces a high expiratory flow from the lungs, simulating a cough. This technique, referred to as "mechanical insufflation-exsufflation," avoids airway damage while clearing the lungs of secretions. The device offers patient’s greater comfort and quality of life without the use of invasive procedures and equipment. Patients as young as 4 months have been able to use the Cough Assist™ successfully.

Respiratory distress can be monitored by measuring the level of oxygen saturation in the blood using a tool called a pulse oximeter. A small clip or tape with a red light and a sensor is placed on the patient’s finger or toe to determine the oxygen saturation. Children with SMA Type I usually require breathing support while sleeping. Some children require more breathing support, especially with colds. There are several options to consider.

  • BiPAP (Bilevel Positive Airway Pressure) uses a nasal mask with a cap, which fits over the head to hold it in place over the nose. BiPAP provides a higher volume of air into the lungs during inhalation and inflates the lung greater than what the person can do on their own. During exhalation, the BiPAP pressure drops so that air can passively leave the lungs. The BiPAP machine can sense when the person is taking a breath and give the breath in synchrony with the individual. A respiratory rate is also set so that the BiPAP gives a minimum number of breaths per minute. The person can breathe above that rate and the BiPAP will deliver more breaths. CPAP (continuous positive air pressure) should never be used in patients with SMA.
  • Negative Pressure Ventilation refers to providing breaths into the lungs using a large chamber or tank that encircles the chest similar to the old Iron Lung. The chamber is connected to a vacuum pump that takes the air out of the chamber and, as a result, the chest wall expands to bring air into the lungs. A Port-A-Lung is an example of a negative pressure ventilator. It can be set to deliver a specific number of breaths per minute and a vacuum pressure.
  • Mechanical ventilators or respirators come in a variety of models. Mechanical ventilators are more complex, but also allow for control of more variables. The ventilator can be set to deliver a specific size breath at a set number of breaths per minute. Mechanical ventilation can be delivered with a nose mask, mouthpiece while awake, or through a tracheostomy tube. A tracheotomy is placement of a surgical hole in the neck to the large airway (trachea) that a tube can be inserted. A tracheostomy tube bypasses the mouth and vocal cords and goes directly from the skin to the trachea (wind-pipe). A respirator or ventilator is connected to the endotracheal tube or tracheostomy tube.

Consult your physicians and respiratory therapists for literature.

SPINAL MASCULAR ATROPHY - Type II (and some Type III)

It is important to get your child upright at the earliest possible age. Standing is important in development. It allows for better respiratory function, improved bowel function, and encourages greater mobility. Getting your child in an upright position may sometimes require advocacy on the part of the parents to encourage the physician to write a prescription for standing aids.

There are several options to consider when choosing the appropriate standing aid.

One option is a standing frame and/or parapodium. For added mobility and independence a standing wheelchair is ideal. A child as young as 13 months can use this. Bracing is also an option. Reciprocating GaitOrthosis (RGO's) and weight bearing knee ankle foot orthoses (KAFO’s) have been found to work for children with Type II, and these children have been able to take some steps. Use of the appropriate type of assistive device or walker with braces is important and various options should be explored with your therapist.

The use of a light-weight manual wheelchair can be an exciting addition for the SMA child. It can provide mobility, independence and a taste of adventure, while still allowing them to use some of their own strength. However, it should be understood that for true independence and mobility, a power wheelchair is necessary.

Scoliosis (curvature of the spine) occurs at some point in essentially all children with SMA Type I and II and some Type III. The degree of the scoliosis will be a factor in deciding how to treat it. Because scoliosis can restrict breathing and pulmonary function, necessary precautions should be taken early. Options for managing scoliosis are: custom seating systems, seating aids and a body jacket. Later, spinal fusion surgery may need to be considered.

If your child has frequent colds and difficulty coughing you may want to inquire about a cough assist machine. The Cough Assist™ is discussed in more detail in the Type I section.

Diet, as with any growing child, is very important. Your child's diet deserves careful consideration. Excessive weight can make mobility more difficult. Constant contact with your physician and a nutritionist is very important in this aspect of care.

SPINAL MASCULAR ATROPHY - Type III

Because children with Type III walk at some point unassisted, it is important that they be monitored so that any difficulty may be detected at an early stage. The use of a walker and bracing may become necessary. The use of a light-weight manual wheelchair may be considered for distance as well as an electric scooter or other motorized chair Physical and Occupational Therapists should be consulted. Diet should also be monitored.

SPINAL MASCULAR ATROPHY - Type IV: Adult Onset

As an adult you are aware of your weaknesses and limitations. You should work together with your physician, physical and occupational therapist to work out the best possible program for you. As with Types I, II, and III, diet and nutrition are an important factor in your well-being.

(Reference: www.fsma.org)