What are the signs of mild cerebral palsy (CP)?

Signs of Mild Cerebral Palsy

Mild cerebral palsy is characterized by subtle motor dysfunction, including asymmetrical movements, delayed motor milestones, and abnormal quality of movement that may not be immediately apparent until the child attempts more complex motor skills. 1

Early Motor Signs

• Asymmetrical hand use: One-handed reaching or manipulation of objects while the other hand is less active 1
• Delayed motor milestones: Not sitting by 9 months or delayed crawling/walking 1
• Abnormal quality of movement: Movements may appear stiff, jerky, or uncoordinated compared to typically developing children 1
• Normal early motor skills: Children with mild CP, especially unilateral CP, often master early rudimentary motor skills (smiling, swallowing, head control) but show difficulties with more complex skills 1

Movement Patterns by CP Type

Mild Spastic CP (Most Common - 85-91% of Cases)

• Unilateral (Hemiplegia):
  • Early hand preference before 12 months
  • Asymmetrical crawling or bunny hopping
  • Toe walking on affected side
  • Decreased range of motion in affected limbs 1, 2

Mild Dyskinetic CP (4-7% of Cases)

• Subtle involuntary movements that worsen with voluntary activity
• Mild dystonic posturing during certain activities 1

Mild Ataxic CP (4-6% of Cases)

• Mild incoordination during fine motor tasks
• Slightly wide-based gait
• Mild tremor with purposeful movements 1

Functional Capabilities in Mild CP

In high-income countries, among all individuals with CP (including mild cases):

• 2 in 3 will walk independently
• 3 in 4 will develop normal speech
• 1 in 2 will have normal intelligence 1

Children with mild CP typically fall into GMFCS Level I, meaning they can walk without limitations but may have difficulties with speed, balance, and coordination 1.

Diagnostic Challenges in Mild CP

• False negatives: Mild CP may be missed because:

  • Children often achieve motor milestones on time initially
  • Neuroimaging may be normal in approximately 10% of cases
  • Clinical signs may emerge gradually 1

• Milder presentations: A child may score within normal range on standardized motor assessments while still displaying abnormal movement patterns (e.g., completing tasks one-handed) 1

Associated Signs Beyond Motor Function

Even in mild CP, be alert for:

• Subtle cognitive or learning difficulties
• Mild speech delays
• Visual or hearing impairments
• Behavioral challenges 1, 2

When to Suspect Mild CP

• Parent/caregiver concerns about asymmetrical movement
• Persistent toe walking on one side
• Hand preference before 12 months of age
• Difficulty with age-appropriate fine motor skills despite normal gross motor development
• Subtle differences in muscle tone (slightly increased or decreased) 1

Important Caveats

1. Evolving presentation: Motor types and topography may emerge and change during the first 2 years of life 1

2. Genetic factors: Recent evidence shows genetic factors play a substantial role in approximately 31% of CP cases, even in mild presentations without intellectual disability 3

3. Differential diagnosis: Some genetic and metabolic conditions can mimic mild CP but are progressive, making accurate diagnosis crucial 4

4. Early intervention: Early identification and referral for CP-specific intervention is critical to optimize motor and cognitive outcomes 1