Neurological examination across childhood — branching viva

A four-month-old infant born at 30 weeks gestation, assessed at corrected age, is found in the neonatal follow-up clinic to have increased tone and brisk reflexes down the right side with absent fidgety movements on General Movements Assessment. The examiner asks: how do you read an extensor plantar and a few beats of clonus in a four-month-old, how do you assess and classify the tone, what does the absent fidgety movement finding mean and what is the early-detection pathway — then branches to a three-month-old floppy, alert infant with areflexia and tongue fasciculations and asks you to split central from peripheral and name the likely diagnosis and its urgency — before closing on the same child at age four with cerebral palsy, asking you to assign a Gross Motor Function Classification System level and defend the prognosis.