A routine surgery in Wales took a terrible turn when a giant light broke free during surgery and bashed the patient over the head.

The procedure was stopped because the surgeon also suffered a concussion and had to receive treatment himself, The Sun reported.

The patient was sedated at the time, but when he woke up he discovered that he needed even more treatment — for a split lip and facial injuries.

An investigation was immediately launched into why the 28-pound lamp broke free.

“Investigations revealed that a screw had worked loose on the swivel bracket that holds the lamp," a hospital spokesman said. "The surgeon has since contacted the patient at home to explain what occurred and offered our sincere apologies.”

All other lamps at Glan Clwyd Hospital, in North Wales, and neighboring hospitals were checked for similar faults.

The patient had the operation a week later.

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