Neuromuscular Scoliosis

Etiology

Common underlying conditions:

Upper Motor Neuron Disorders

• Cerebral palsy

• Traumatic brain injury

Lower Motor Neuron Disorders

• Spinal muscular atrophy

• Poliomyelitis

Myopathies

• Duchenne muscular dystrophy

• Other muscular dystrophies

Epidemiology

• High prevalence in severe neuromuscular disease

• Curve progression strongly associated with:

  • Loss of ambulation

• More severe and progressive than idiopathic scoliosis

Pathophysiology

• Muscle imbalance → asymmetric spinal loading

• Poor trunk control → progressive deformity

• Leads to:

  • Long C-shaped curves

  • Pelvic obliquity

  • Sagittal imbalance

Clinical Presentation

• Progressive spinal deformity

• Sitting imbalance

• Pelvic obliquity

• Difficulty with:

  • Sitting

  • Care (hygiene, positioning)

• Pain (less prominent than adult scoliosis)

• Respiratory compromise (advanced cases)

Imaging

• Standing or sitting AP and lateral X-rays

• Assess:

  • Cobb angle

  • Pelvic obliquity

  • Sagittal alignment

Natural History

• Typically progressive

• Rapid progression after:

  • Loss of ambulation

• Large curves may lead to:

  • Respiratory dysfunction

  • Poor quality of life

Treatment

Nonoperative

Indications

• Mild deformity

• Early stages

Options

• Seating modifications

• Bracing (limited effectiveness)

• Physiotherapy

Bracing does NOT prevent progression but may improve sitting balance

Operative Treatment

Indications

• Progressive curve (>40–50°)

• Sitting imbalance

• Pelvic obliquity

• Functional impairment

Surgical Goals

• Improve sitting balance

• Correct deformity

• Achieve pelvic alignment

• Facilitate care

Surgical Options

• Posterior spinal fusion (most common)

• Long-segment instrumentation

• Pelvic fixation (if pelvic obliquity present)

Perioperative Considerations

• High-risk population

• Requires multidisciplinary care:

  • Pulmonary evaluation

  • Nutritional optimisation

  • Cardiac assessment

Complications

• Infection

• Blood loss

• Implant failure

• Pseudarthrosis

• Pulmonary complications

Prognosis

• Surgery improves:

  • Sitting balance

  • Quality of life

• Does NOT reverse underlying neuromuscular disease

Pits & Pearls

• Neuromuscular scoliosis = long, flexible, progressive curves

• Pelvic obliquity is a key surgical driver

• Bracing is supportive, not corrective

• Surgery aims at function, not perfect correction

Pitfalls

• Delaying surgery until curves become very large

• Ignoring pelvic alignment

• Underestimating perioperative risks

• Expecting cosmetic outcomes

Mini Decision Algorithm