Jon Hutt was doing some logging work alone in a remote Colorado forest when his six-ton trailer fell on his right foot.
His pain was immense but there was no one around to help him and he couldn't reach his cellphone, which was in his truck and out of range anyway.
So he pulled out his three-inch pocket knife and cut off his toes to get free.
Hutt said he had to do it before he lost his strength.
"I looked it over and I thought, well I better cut this off before I go into shock or drop this pocket knife," said Hutt. "Got the boot cut away then I could see that those toes have been crushed, you know, basically off. I just decided I better get it done when I could."
Hutt managed to get on his semi tractor-trailor with his foot wrapped in a shirt, and began driving for help.
Authorities retrieved his toes but doctors said they could not re-attach them because they were too badly mangled. Instead, doctors sewed his foot shut and wrapped it in bandages. Doctors warned him he may face more surgery.
Hutt said he never thought about the 2003 ordeal of Aaron Ralston, who amputated his right arm after it was pinned beneath a boulder in a Utah canyon, until someone reminded him about it at the hospital.
Ralston's story became the subject of the movie "127 Hours."
The Associated Press contributed to this report.