What is the scoring system for the Hammersmith (neonatal neurological examination) in newborns?

Hammersmith Neonatal Neurological Examination Scoring

The Hammersmith Infant Neurological Examination (HINE) uses a standardized scoring system where total scores range from 0-78, with specific cutoff values at different ages to predict cerebral palsy risk: scores <57 at 3 months indicate 96% predictive value for CP, scores <73 at 6-12 months indicate high CP risk, and scores <40 at 6-12 months almost always indicate CP. 1, 2

Scoring Structure and Components

The HINE evaluates infants from 2-24 months of age using multiple domains that contribute to the total optimality score of 78 points 3, 4:

• Cranial nerve function - assessed and scored as part of the neurological evaluation 5
• Posture - including trunk posture evaluation 4
• Movements - both quantity and quality of spontaneous movements 5, 4
• Tone - measured through specific maneuvers including scarf sign, hip adductor angles, and popliteal angle 4
• Reflexes and reactions - including tendon reflexes, pull to sit, lateral tilting, and forward parachute reaction 5, 4
• Asymmetries - documented separately as a critical indicator 5

Age-Specific Cutoff Scores for CP Prediction

Before 5 Months Corrected Age

• Score <57 at 3 months: 96% predictive of cerebral palsy 1, 2
• HINE demonstrates 90% sensitivity for detecting CP risk in this age group 1

Between 6-12 Months Corrected Age

• Score <73: Indicates high risk of cerebral palsy 1
• Score <40: Almost always indicates CP (abnormal outcome) 1
• HINE maintains 90% predictive accuracy for CP at ages 2-24 months 1

Severity and Topography Prediction (3-12 months)

• Score 50-73: Likely indicates unilateral CP (95-99% will walk) 1
• Score <50: Likely indicates bilateral CP 1
• Score 40-60: Likely GMFCS levels I-II 1
• Score <40: Likely GMFCS levels III-V 1

Scoring Methodology

Each item is scored against age-specific optimal values, with points awarded based on how closely the infant's performance matches expected developmental milestones 4. The examination should be performed systematically, documenting both the global score and individual subscores 5.

The weighted combination of HINE subscores and asymmetries outperforms the global HINE score alone in predicting CP, with multivariable models achieving AUC of 0.91 compared to 0.75 for global scores alone. 5

Critical Subscores with Highest Predictive Value

Individual subscore analysis reveals specific domains with superior predictive accuracy 5:

• Reflexes and reactions: AUC 0.80 for CP prediction 5
• Cranial nerve function: AUC 0.76 5
• Asymmetries: AUC 0.75 5
• Movements: AUC 0.71 5

Timing of Assessment

HINE can be performed earlier than traditionally recommended without losing predictive accuracy - assessment before discharge (HINE PE) demonstrates equivalent predictive ability to assessment at recommended age (HINE RA), with similar AUC values of 0.71 versus 0.66 and identical cutoff optimality score of 32.5. 6 This provides several weeks of lead time for early intervention 6.

Longitudinal Trajectory Patterns

HINE scores demonstrate different patterns based on underlying etiology 3:

• Perinatal arterial ischemic stroke (PAIS): Shows 10.8-point increase in total HINE scores after 9 months of age, with 2.9-point increase in asymmetry scores 3
• HIE, prematurity-associated brain injury, and congenital malformations: HINE scores remain stable throughout the first two years without significant improvement 3

Brief-HINE Screening Version

A validated 11-item screening tool exists with age-specific cutoffs 4:

• 3 months: Score <22 (sensitivity 0.88, specificity 0.92) 4
• 6 months: Score <25 (sensitivity 0.93, specificity 0.87) 4
• 9 months: Score <27 (sensitivity 0.95, specificity 0.81) 4
• 12 months: Score <27 (sensitivity 1.0, specificity 0.86) 4

More than one warning sign or non-optimal items mandate full HINE reassessment 4.

Clinical Application Pitfalls

Never rely on HINE scores in isolation - combine with MRI findings and clinical history for diagnostic accuracy exceeding 95% 1, 2. Normal neuroimaging does not automatically preclude CP diagnosis when HINE scores are abnormal 1.

Serial assessments every 4-6 months are essential - tracking individual trajectory changes aids diagnosis, informs prognosis, and guides clinical trial design 3. Single timepoint assessments miss evolving patterns, particularly in PAIS cases where improvement occurs after 9 months 3.