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Updated: Apr 21, 2026

A Battery of Motor Tests in a Neonatal Mouse Model of Cerebral Palsy
Published on: November 3, 2016
[Stiff baby syndrome is a rare cause of neonatal hypertonicity]
Maria Sode Rønne1, Preben Berg Nielsen, Christian Backer Mogensen
1Frueløkke 115, 6200 Aabenraa. ms.roenne@gmail.com.
Abstract:
Stiff baby syndrome (hyperekplexia) is a rare genetic disorder. The condition can easily be misdiagnosed as epilepsy or severe sepsis because of hypertonicity and seizure-like episodes and has an increased risk of severe apnoea and sudden infant death. Tapping of the nasal bridge inducing a startle response is the clinical hallmark. We report cases of two sisters born with stiff baby syndrome with hypertonicity, exaggerated startle reaction and cyanosis. The syndrome has a good prognosis if treated with clonazepam and both cases were developmental normal after one year.
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