Approaching the Neurologic Assessment of the Infant Study Notes

Presentation Overview

  • Title: Approaching the Neurologic Assessment of the Infant
  • Speakers:
    • Samantha Weaver, DNP, CRNP, CPNP-AC, CNRN - University of Alabama at Birmingham
    • Amy Vierhile, DNP, RN, PPCNP-BC - University of Rochester Medical Center
  • Event Details:
    • Event: 2025 Pediatric Virtual Symposium
    • Date: Live on Oct. 10, 2025
    • Access: Sessions available through Dec. 31, 2025
  • Disclosure: Speakers have no disclosures relevant to the presentation and will not discuss any off-label medication uses.

Learning Objectives

  • By the end of the presentation, participants will learn to:
    • Identify both normal and abnormal neurodevelopmental findings.
    • Review key components of the infant neurologic exam.
    • Discuss strategies and maneuvers for infant assessment.
    • Explain the clinical significance and prognostic value of specific neurologic findings.
    • Understand when to refer to other specialties or services.

Pre-Examination Considerations

  • History of Present Illness:
    • Gather details on onset, duration, patterns, and inciting or provoking features.
  • Birth History:
    • Assess gestational age, ante and perinatal history, maternal or infant infections/newborn screening results.
  • Developmental History:
    • Review infant’s development to date, feeding and sleeping habits, medications, general health & surgical history, and family & social history.
  • Sources for Reference:
    • Cited studies by James & Piña-Garza (2025), Baston & Durward (2025), and information from Stanford Medical.

Assessment Approach

  • Mental Status Exam:
    • Age-dependent aspects to consider include wakefulness and gestational age.
    • Incorporate other systems for a comprehensive assessment.
  • Behavioral Analysis:
    • Assess alertness, awareness, and responsiveness to the environment, including maintaining gaze or attention.
  • Head Shape & Size Assessment:
    • Evaluate fontanelles (both anterior and posterior) for signs of abnormal closure, swelling, or sunken areas.
    • Check for signs of plagiocephaly, torticollis, craniosynostosis or dysmorphia.

Neurologic Assessment Components

  • Head Circumference Evaluation:
    • Method: Measure frontal-occipital circumference.
    • Macrocephaly: Defined as greater than the 97th percentile, with differential diagnosis including familial benign macrocephaly or hydrocephalus.
    • HC crossing over 1+ major percentile or increasing by 2+ cm/month before 6 months should prompt ultrasound if the fontanel is still open.
    • Microcephaly: Defined as less than the 3rd percentile, with potential differential diagnoses such as infections, perinatal exposures, genetic conditions, or brain malformations.
  • Neurocutaneous Skin Findings:
    • Evaluate for skin findings like café-au-lait spots, port-wine stains, angiofibromas, and ash leaf macules which could indicate conditions like neurofibromatosis or Sturge-Weber syndrome.
    • Assess for sacral dimpling concerning spina bifida occulta based on size and presence of other abnormal skin changes.

Motor System Evaluation

  • Tone & Movements:
    • Observations to include symmetric spontaneous movements, regular respiratory patterns, and resting tone as measured through natural flexion while the infant is awake.
    • Signs to observe for:
    • Muscle atrophy, contractures, tremors, or twitching.
    • Potential hip dysplasia.
  • Hypotonia Indicators:
    • Defined as reduced resting tension, often seen in the ‘floppy infant’ with signs of poor feeding and apneic spells.
    • Postures might include abducted hips and internally rotated shoulders with extended elbows and knees.
    • Hypotonia may also present in conditions like arthrogryposis (characterized by contractures).

Assessment Maneuvers for Tone

  • Types of Low Tone Maneuvers:
    • Horizontal Suspension: Assess infant's tone while lifting in a prone position with supported chest and abdomen.
    • Vertical Suspension: Lift infant under the arms to assess overall muscle tone.
    • Scarf Sign: Observing that the hand does not move past the shoulder and that the elbow does not cross midline.
    • Pull-to-sit: Gently pulling the infant to sitting to assess head lag (mild lag is normal until 2 months).
    • Barlow Maneuver: Assess for dislocated hip through hip adduction.
    • Ortolani Maneuver: Assess for hip abduction to correct any dislocation observed.

Tone Variability Conditions

  • Hypertonia/Spasticity Characteristics:
    • Defined as high tension, present at birth or may develop over time.
    • Symptoms may include tremors, jerky movements, rigid limbs, and difficulty in arm and leg movements at rest.

Primitive Reflexes and Their Significance

  • Exploration of Primitive Reflexes:
    • Rooting/Sucking Reflex: Present at ages 0-3 months, critical for feeding.
    • Tonic Labyrinthine Reflex: Aids in maintaining balance and posture, present from ages 0-3 months.
    • Moro (Startle) Reflex: Present at 1-6 months for balance and protective responses.
    • Asymmetrical Tonic Neck Reflex (Fencing): Present from birth to 6 months; critical for balance.
    • Symmetric Tonic Neck Reflex: Appears from 6-9 months aiding in crawling.
    • Babinski Reflex: Present from 0-2 years; tests corticospinal tract response by stroking the sole of the foot with a positive response being an upward motion.

Conclusion and Summary

  • The infant neurological examination should begin with a comprehensive history of both the baby and mother.
  • It synthesizes skilled observation and assessment maneuvers keeping in mind gestational age and neurotypical milestones, with a recognition of possible urgent conditions.

References

  • A detailed list of references is provided towards the end of the presentation, including studies from experts in pediatrics that further substantiate the information provided in the presentation.