Image caption A lump over the blade burned and irritated McNeely

Doctors in Canada have removed a knife blade from a man's back more than three years after he was stabbed in a fight.

Billy McNeely of the Northwest Territories told local media he had suffered itching and minor pain but did not know the blade was still embedded.

This week, his nail caught the tip of the 7.5cm blade and uncovered it.

"I've done some jail time in the past," he said. "The guards rub over you with a metal wand detector, and every time it hit my back... it went off."

In April 2010, McNeely got into a fight after an arm wrestling match and was stabbed five times, he told the Canadian Press news agency.

Doctors at the local accident and emergency room stitched him up but never took an X-ray, he said. Seeking subsequent treatment for the lingering discomfort, he was told he had suffered nerve damage.

But this week, McNeely, 32, was scratching his back as usual when his fingernail caught on something. His girlfriend took a look.

"I told Billy: 'There's a knife sticking out of your back.' I was scared. I was ready to pull it out with tweezers," Stephanie Sayine told CBC News.

McNeely is considering whether to file a lawsuit against the local health department.