What are the other Names for this Condition? (Also known as/Synonyms)

• Curved Spine due to Neuromuscular Scoliosis
• Neuromuscular Idiopathic Scoliosis

What is Neuromuscular Scoliosis? (Definition/Background Information)

• Scoliosis is a common medical disorder characterized by abnormal curvature of the spine; a side to side spinal curve is observed. This disorder is caused by a defect that causes the spine (or the backbone) to bend or curve sideways, to look like an “S” or “C” instead of an “I”
• Even though bone malformations may be present in newborn infants at birth, Scoliosis may not develop until the child reaches adolescence
• It is a hereditary condition, which means the disorder can be passed on through generations; the condition may run in the family
• Neuromuscular Scoliosis is a common form of scoliosis that is associated with neuromuscular disorders. These disorders may include cerebral palsy, muscular dystrophy, paralysis from spinal cord injury, spinal muscular atrophy (SMA), etc.
• These neuromuscular conditions cause the muscles to become weak and paralyzed and it is no longer able to support the spine. This results in an abnormal curvature of the spine
• Children with underlying neuromuscular disease are typically affected by Neuromuscular Scoliosis. The condition is more severe in those who are unable to walk due to neuromuscular disease
• Neuromuscular Scoliosis usually occurs as a “C” type curve and it has a progressive nature. It usually continues to progress into adulthood and is worse during the growth spurts
• Bracing method of treatment is not effective for this condition and hence, spinal fusion surgery may be required
• Neuromuscular Scoliosis is associated with various neuromuscular conditions. The severity of scoliosis or abnormal spinal curvature is dependent upon the severity of the neuromuscular condition. The associated conditions/disorders include:

Neuropathic conditions:

• Upper and motor neuron lesion
  • Cerebral palsy
  • Syringomyelia
  • Spinal cord trauma
• Lower motor neuron lesion
  • Poliomyelitis
  • Spinal muscular atrophy
• Myopathic conditions:
  • Arthrogryposis
  • Muscular dystrophy
  • Other forms of myopathy

Who gets Neuromuscular Scoliosis? (Age and Sex Distribution)

• Neuromuscular Scoliosis affects children with neuromuscular disorders such as cerebral palsy, polio, muscular dystrophy, etc. The condition progresses into adulthood
• It is observed in both male and female children and is gender non-specific
• Racial, ethnic, and geographical predominance is not observed

What are the Risk Factors for Neuromuscular Scoliosis? (Predisposing Factors)

The risk factors for Neuromuscular Scoliosis include:

• Non-ambulatory children with cerebral palsy that has affected both the legs and arms (quadriplegic)
• Children with spina bifida with a high level of paralysis
• Children who are affected by spinal cord paralysis before the age of 10 years.

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Neuromuscular Scoliosis? (Etiology)

• Neuromuscular Scoliosis is the second most common form of scoliosis and is associated with disorders of the nerves and muscular systems (neuromuscular systems)
• These disorders include cerebral palsy, spina bifida, muscular dystrophy, paralysis from spinal cord injury, myopathy, poliomyelitis, spinal cord tumors, and spinal muscular atrophy
• The abnormal spinal curvature occurs because of weak and paralyzed nerves and muscles that are unable to support the spine
• The severity of the neuromuscular disorder plays a role in the degree of curvature of the spine. The greater the severity of the disorder, the higher may be the extent of scoliosis
• Neuromuscular Scoliosis may be defined as an abnormally curved spine caused by defects in the muscle-nerve (myoneural) pathways of the body

More research is underway to know the exact cause for the incidence of Neuromuscular Scoliosis.

What are the Signs and Symptoms of Neuromuscular Scoliosis?

The symptoms and signs of Neuromuscular Scoliosis may be manifested as:

• Decreasing ability of the individual to sit; sitting stability is severely affected
• Pelvic obliquity is seen that can lead to sitting intolerance
• Individuals may or may not be able to walk
• Pressure sores or ulcers (skin breakdown is observed)
• Changes in the overall position of the body parts
• Trunk imbalance is commonly observed
• Head is not centered with the rest of the body
• The patient begins to lean forward to one side or has an uneven seating posture
• Increased need for using the arms for seating support
• Uneven height of the shoulders (shoulder blade), uneven height and position of the hip
• An uneven buttock is also common
• Hands hang in an uneven fashion beside his body
• When the patient bends forward, the left and right side of the body appears to be different in height

How is Neuromuscular Scoliosis Diagnosed?

A thorough assessment of all the body systems is necessary to ensure proper diagnosis of Neuromuscular Scoliosis.

• An accurate diagnosis of the underlying condition is essential and may require muscle biopsy
• Assessment of the nutritional status and pulmonary function is very important
• The child’s caretaker must be interviewed to understand the child’s functional level

Neuromuscular Scoliosis is diagnosed using the following methods:

• A thorough physical examination, correlated with a complete medical history including family and social history, which is done to determine the nature, extent, and effect of scoliosis affecting the child and also to assess the underlying neuromuscular diseases
• The child’s caretaking team may evaluate the child for:
  • Nutritional status
  • Lung and heart function
  • Functional level
  • Joints and extremities
  • Balance and ambulatory level
• Other tests that may be performed include:
  • X-ray, MRI (magnetic resonance imaging), or CT (computerized tomography) scans
  • Blood tests
  • Ultrasound or sonogram
  • Bone scans
  • Bone density test using dual-energy X-ray absorptiometry, DEXA, DXA methods
  • Muscle biopsy
  • Pulmonary function tests
  • Electromyogram (EMG)
  • Nerve conduction studies.
  • Orthopedic examination is conducted to assess the extremities and joints for contractures
  • Spinal deformity/decompensation and shoulder balance may be checked
  • Ambulatory status is evaluated
  • Total lymphocyte counts are tested
  • Albumin tests: It has been reported that the patients with serum and albumin levels greater than 3.5 mg have lower incidence of post-operative wound infection

Tests to assess the nutritional status may include:

• Hemoglobin test is conducted to assess the nutritional status and if blood transfusion is required
• Total protein test
• Electrolyte tests are done to check electrolyte levels and evaluate the nutritional status
• Blood urea nitrogen test
• Creatinine levels
• Transferrin studies are done to identify malnourished patients

Other imaging studies conducted to diagnose Neuromuscular Scoliosis can include:

• Suprine  anteroposterior and lateral  spinal radiographs in very young patients and older patients having sitting disabilities
• Upright anteroposterior and lateral spinal radiographs
  • Standing upright radiographs are used for patients who can stand
  • Sitting radiographs are used for patients who cannot stand
  • Standing patients do not use supporting devices like crutches        
  • Sitting patients do not use the hands for support during radiographs
  • Radiographs give an accurate picture on the magnitude of the spinal deformity, pelvic obliquity, and spinal balance
• Traction spinal radiographs are used to evaluate flexibility of the curve

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Neuromuscular Scoliosis?

The complications due to Neuromuscular Scoliosis could include:

• Collapsed torso, contracture of hip and knees
• Raised diaphragm
• Reduced lung space, lung function is affected and there is an increased risk of pneumonia
• Vision, hearing loss
• Seizures
• Respiratory conditions: The child is likely to be affected by post-operative pneumonia
• Wound problems: Skin breakdown and infections are likely to occur
• Nutritional/feeding related problems: A feeding tube may be required, until the child is able to feed orally
• Hip deformities: Stiff and abnormal hips are commonly observed. The existing hip contractures tend to worsen further
• Intestinal obstruction: This is an end result of intestinal sluggishness that is medically termed as hypomotility

Severity of the curves tends to increase with the degree of neuromuscular involvement.

• Pulmonary abnormalities arise due to larger thoracic curves over 80 degrees
• Cerebral palsy with 2 limb involvement leads to 25% incidence of scoliosis
• Cerebral palsy with 4 limb involvement - 80%
• Myelodysplasia (lower lumbar) - 60%
• Myelodysplasia (thoracic level) - 100%
• Spinal muscle atrophy - 67%
• Friedreich’s ataxia - 80%
• Duchenne muscular dystrophy – 90%
• Traumatic paralysis over 10 years can lead to 100% incidence of scoliosis

How is Neuromuscular Scoliosis Treated?

Treatment methods that may be adopted to manage Neuromuscular Scoliosis will depend on the following factors:

• Nature and severity of the curves
• The age of the patient during onset
• The current age of the patient
• The rate of progression of the curves
• The underlying neuromuscular disease that has caused scoliosis
• General health status of the patient
• The management choice of the patient’s family

The expertise of a multidisciplinary team is needed to evaluate and treat the patients. Experts with background in pulmonary, neurologic, genitourinary, orthopedic, nutritional and gastroenterological disciplines are often needed.

The treatment for Neuromuscular Scoliosis may include both surgical and non-surgical methods.

Non-surgical treatments methods may include:

• Bracing: A brace will help provide support to the spine and retain it in a balanced position over the pelvis. A suitable bracing technique can help in improving one’s sitting capability and also delay the process of surgical stabilization
• Physical therapy:
  • The aim is to improve one’s physical functioning
  • Special exercise programs may be charted along with additional therapies to reduce pain and muscular imbalance caused by spinal abnormalities
• Wheelchair modification
• Environmental adaptation

Surgical therapy - surgery is recommended based on the following parameters:

• Curve progression
• Deterioration in the sitting ability of the patient
• Before the surgery, the surgeon may assess the patient in relation to:
  • Lung and heart function
  • Nutritional and protein status
  • If the child might suffer from postoperative feeding difficulties
  • Neurologic status
  • Use of seizure medications
  • Urologic status
  • Bone health
  • Swallowing and regurgitation evaluation, especially in case of cerebral palsy
  • Clotting and bleeding evaluation

Spinal fusion surgery: This surgical technique is the most common method of treatment for those who have reached their adolescence stage. The treatment will depend on the type and severity of the disease. The aim of spinal fusion surgery is to:

• Stabilize the curve
• Stop progression of Neuromuscular Scoliosis
• Bring about a balance of the spine and pelvis
• Enable patients to sit upright
• Improve the functions of the lung

In this surgery, metal rods, hooks, screws, and wires are used to correct the spinal curve and balance the spine and the pelvis. A combined anterior/posterior approach will be needed because:

• Some posterior elements may be missing
• It is an effective method to achieve a balance between the spine and the pelvis

When a very young child is affected by neuromuscular scoliosis user friendly surgical procedures may be used which will include:

• Use of growing rods/VEPTR. Metal rods are inserted that will help in controlling the spinal curve, until the child is ready for a spinal fusion procedure
• It should be noted that as the child grows the rods are made longer

Post-operative care:

• After the surgery, the patients may be put in intensive care unit. Some patients may require ventilator support while in the ICU
• The duration of the hospital stay is generally between 5-10 days, but this depends upon the severity of the condition
• During this post-operative period, the patient is carefully monitored especially for the function of the lungs, fluid, and nutrition levels

Nutritional deficiencies should be corrected pre-operatively through a nutritional improvement schedule or with the use of feeding tubes which includes:

• Elective placement of gastric feeding tubes 3 months post-operatively
• Total parenteral nutrition done pre-operatively helps in decreasing problems with wound infections

How can Neuromuscular Scoliosis be Prevented?

• Neuromuscular Scoliosis is associated with certain underlying neuromuscular disorders and currently, there are no definitive methods available to prevent this disorder
• The underlying neuromuscular conditions are treated to minimize the severity of scoliosis

What is the Prognosis of Neuromuscular Scoliosis? (Outcomes/Resolutions)

The long-term outlook of Neuromuscular Scoliosis generally depends upon the severity and extent of the underlying neuromuscular conditions.

With successful surgery and post-operative care the child can:

• Return to his/her normal functioning level to the extent possible
• The spine will be solidly fused; balance and the deformity will be considerably reduced
• Have an improved lung functioning
• There is a decreased risk of being susceptible to pneumonia
• Will find it easier to sit up straight

Additional and Relevant Useful Information for Neuromuscular Scoliosis:

• Patients with vital capacities less than 30% reference value may require post-operative ventilator support
• Pulmonary function studies may be required before surgery, but this study is possible only if the patients are able to cooperate
• Patients suffering from Duchenne muscular dystrophy and Friedreich’s ataxia should be checked for cardiac involvement