In the Hammersmith Infant Neurological Examination (HINE), how is each component (cranial nerve function, posture, movements, tone, reflexes, and reactions) scored, and how is the total score interpreted?

Hammersmith Infant Neurological Examination (HINE) Scoring and Interpretation

The HINE consists of 26 scorable items across 5 domains (cranial nerve function, posture, movements, tone, and reflexes/reactions), with each item scored individually and summed to create a global score out of 78 points, where specific cutoff scores predict cerebral palsy risk and motor severity based on the infant's age. 1, 2

Scoring Structure

The HINE assessment includes 2:

• 26 scorable items divided into 5 domains:

  • Cranial nerve function
  • Posture
  • Spontaneous movements
  • Tone
  • Reflexes and reactions

• Additional components (not included in global score):

  • 8 items documenting motor function development
  • 3 items evaluating behavioral state
  • Asymmetry scoring (separate from global score)

Each item receives an individual optimality score, and the global score is the sum of all individual scores with a maximum of 78 points 2.

Score Interpretation by Age

At 3 Months (Corrected Age)

Scores <57 are 96% predictive of cerebral palsy 1

• <40: Indicates likely GMFCS III-V (severe, nonambulant CP) 1
• 40-60: Indicates likely GMFCS I-II (mild-moderate, ambulant CP) 1
• 50-73: Suggests likely unilateral CP (95-99% will walk) 1

At 6,9, or 12 Months (Corrected Age)

The HINE demonstrates 90% sensitivity for predicting CP at these ages 1

• <40: Almost always indicates CP (definite abnormal outcome) 1
• <73: Indicates high risk of CP 1
• 50-73: Suggests likely unilateral CP (hemiplegia) with excellent walking prognosis 1
• <50: Indicates likely bilateral CP 1

Asymmetry Scoring

Asymmetry scores are calculated separately and are particularly valuable for detecting hemiplegic CP, which may score within normal ranges on global scores 1, 3.

For identifying hemiplegia 3:

• Asymmetry score >5 combined with total HINE <63 yields 91.8% sensitivity and 100% specificity
• Infants with hemiplegia typically show median asymmetry scores of 10 versus 0 in typically developing infants

Predictive Value of Individual Domains

Movement quality and quantity are the most predictive items across all ages 4. The predictive hierarchy changes with age:

• First 6 months: Tone assessment items are most predictive (after movements) 4
• After 6 months: Reflexes and reactions become most predictive (after movements) 4

Recent evidence suggests that weighted combinations of subscores outperform the global score alone 5:

• "Reflexes and reactions" subscore: AUC = 0.80
• "Cranial nerve function" subscore: AUC = 0.76
• Multivariable model combining subscores: AUC = 0.91 (versus 0.75 for global score alone)

Clinical Application Algorithm

1. Perform complete HINE at appropriate corrected age (3,6,9, or 12 months)

2. Calculate global score and compare to age-specific cutoffs:

   • At 3 months: <57 indicates high CP risk
   • At 6-12 months: <73 indicates high CP risk; <40 indicates definite CP

3. Calculate asymmetry score separately:

   • If asymmetry score >5 with total score <63, strongly suspect hemiplegia

4. Examine individual domain subscores, particularly:

   • Movement quality/quantity (highest predictive value)
   • Tone (if <6 months)
   • Reflexes and reactions (if >6 months)

5. Combine HINE findings with neuroimaging (MRI) for optimal accuracy 1

Important Caveats

Milder presentations, especially unilateral CP, can score within normal ranges on global scores while still displaying abnormal movements 1. For example:

• An infant with hemiplegia may complete assessments one-handed but achieve normal fine motor scores
• An infant with diplegia may have normal upper limb scores but abnormal lower limb scores, producing a falsely normal combined score

Therefore, assessment must be performed by professionals skilled at distinguishing atypical from typical movement variations 1.

Longitudinal trajectories matter: Infants with perinatal arterial ischemic stroke (PAIS) show improving HINE scores over time (estimated 10.8-point increase after 9 months), while those with HIE, prematurity-associated injury, or congenital malformations show stable scores 6. This pattern recognition aids both diagnosis and prognosis.