Bradycardia in minor trauma: don't be slow on the uptake!

We report the case of a 13-year-old boy presenting with profound bradycardia following minor trauma. Our patient had gastroschisis at birth and has moderate learning difficulties but is otherwise fit and well. Whilst playing at home he fell sustaining a minor cervical hyperextension injury. He immediately complained of tetraplegia and hyposensibility. The ambulance crew noted profound bradycardia with normotension and he was transported to hospital with full spinal immobilisation precautions. Over the subsequent 2 hours he made a full neurological recovery. Bradycardia persisted with a beat-to-beat variation of 30-60 bpm. ECG showed sinus bradycardia with atrial ectopics and he remained haemodynamically normal. Neuroimaging studies revealed hypoplasia of the odontoid peg with a relative narrowing of the spinal canal at this level. There was no evidence of spinal cord contusion or compression. His bradycardia resolved over 36 hours without further intervention. On discharge the patient was advised to wear a cervical hard collar when mobilising. This association of a craniocervical abnormality with learning difficulties, and gastroschisis has not been previously described. We discuss several other causes of odontoid peg instability, which may lead to severe autonomic effects with relatively insignificant trauma.