Surgeons have finally got to the bottom of shooting pains a mugging victim felt in her backside — more than four months after she was robbed.

This astonishing X-ray shows the thugs left Ying Shi, 26, with a razor sharp 6-inch blade completely buried in her buttocks.

PHOTOS: Outrageous X-rays

"All I remember of the night was a stabbing pain in my backside," Ying said. "I thought they had just slashed me, I didn't realise the whole blade had gone all the way in."

Doctors in Shanghai, eastern China, were baffled by her complaints of stomach pains — until they sent her for X-rays and found the blade pressing into her bladder.

"I am amazed they missed it the first time around but very relieved that they've found it now," Ying said.

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