When your (kid’s) legs don’t work like they used to before

Authors: Jonathan White, Amy Jones / Editor: Steve Corry-Bass / Reviewers: Sandi Angus / Codes: MuP2, SLO5 / Published: 14/10/2022

A 6-year-old boy is brought to the Emergency Department (ED) by his Mother, with a one day history of refusing to walk. The child is complaining of bilateral leg pain but unable to specify where. His Mother reports that he was experiencing tenderness on light palpation of his lower legs and therefore refusing to allow his legs to be touched.

This follows a five day history of feeling generally unwell, pyrexia and coryzal symptoms. He is usually an active child and is otherwise well with no past medical history, takes no medications and has no known allergies. He has an uncomplicated birth history, normal developmental history and is up to date with childhood vaccinations. There is no history of preceding trauma.

His temperature, heart rate, respiratory rate and oxygen saturations are within normal limits.

On examination, the child refuses to bear weight bilaterally requiring support from his Mother. He can only weight bear on his metatarsals for a matter of seconds. Pain is elicited on passive dorsiflexion bilaterally and with palpation of his calves. Hip and knee flexion and extension reveal a good range of movement, with no joint swelling or skin changes throughout the lower limbs. His cardiorespiratory, abdominal and neurological examinations are all normal.

Bloods (including urea and electrolytes) are unremarkable other than a raised creatine kinase at 2757 U/Litre. His urinalysis is normal.