An unusual cause of constipation presenting to the emergency department.

A case report of a 16-year-old girl who presented to the emergency department with constipation and recurrent urinary tract infections is examined. She gave a history of persistent coccygeal pain stemming from a fall on a trampoline 1 year ago. On examination, she was found to have an abdominal mass arising from the pelvis and paraesthesia of S1-S5 dermatomes in the right leg. An abdominal radiograph showed bony erosion of the sacrum. Magnetic resonance scanning revealed a mass arising from the sacrum and subsequent biopsy diagnosed the tumour as Ewing's sarcoma.