Hammersmith Infant Neurological Examination Asymmetry Score Distinguishes Hemiplegic Cerebral Palsy From Typical Development.

BACKGROUND: The Hammersmith Infant Neurological Examination is one of several useful tools for early identification of cerebral palsy; however, cut-off scores for cerebral palsy do not consistently distinguish infants with hemiplegia from those typically developing. We hypothesized that use of an asymmetry score, in addition to the assessment's standard total cutoff score, could remedy this problem in a clinical setting.

METHODS: This retrospective study of a neonatal intensive care follow-up program with consistent clinical use of the Hammersmith Infant Neurological Examination matched infants with a diagnosis of cerebral palsy to infants without motor delays or evidence of neurodevelopmental impairments. Groups had same corrected and gestational ages at Hammersmith Infant Neurological Examination assessment. Asymmetry presence was recorded.

RESULTS: Of 74 infants with cerebral palsy, 28 had quadriplegia, 11 had diplegia, and 35 had hemiplegia. Median total Hammersmith Infant Neurological Examination and asymmetry scores for hemiplegia were 57.5 and 10 versus 76 and 0 for those without cerebral palsy. Sensitivity and specificity to distinguish hemiplegia from typical development by combining a total Hammersmith Infant Neurological Examination score less than 63 and an asymmetry score greater than 5 were 91.8% and 100%, respectively.

CONCLUSIONS: In a clinical setting, combining total Hammersmith Infant Neurological Examination and asymmetry scores can help providers differentiate infants with hemiplegia from those typically developing.