Generally performing radiographs for sacrococcygeal fractures is a waste of resources and exposes patients to unnecessary ionizing radiation. In one recent American study, they had no measurable impact on clinical outcome ¹.

Indeed it has been best practice in the UK for many years to refuse to perform them for trauma. Anyone experiencing high-energy trauma will have a CT anyway, precluding the necessity of performing these pointless studies.

This particular case "slipped through the net" and was performed despite being contrary to departmental guidelines. No doubt the patient was pleased to have their diagnosis confirmed however it would have had no meaningful consequences for their management as the current standard is discharge home with analgesia.