Rock climber recounts terrifying moment he was forced to amputate his own arm to survive

Warning: This article contains graphic descriptions which some readers may find distressing.

A rock climber was forced to cut his own arm off to survive after becoming stuck in a canyon.

Mountaineer and mechanical engineer Aron Ralston was on a solo expedition of the Bluejohn Canyon in southeastern Utah on April 26, 2003 when a boulder dislodged and his arm became trapped.

Prepare yourself, Ralston's recollection of the incident is not for the faint-hearted:

Ralston's right wrist becoming trapped under the boulder led him to be stuck in the canyon for five days with nothing but a video camera, headphones, a multi-tool kit, one litre of water, two burritos and a few chunks of chocolate, as per The Guardian.

Most notably, Ralston had no phone with him and subsequently no way to call for help.

So, on the fifth day, in a desperate bid to survive, the then-27-year-old decided to take drastic action - he would cut off part of his arm in a bid to free himself.

In an interview with TLC, Ralston explained how he went about the harrowing DIY surgical procedure in hair-raising detail.

Aron Ralston cut off his lower arm below the elbow to break free of the boulder. (Gretel Daugherty/Getty Images)

In a clip of the interview shared to X, Ralston can be heard explaining his hand had been 'decomposing' over the five days.

He said: "It was a gruesome concept that my hand was decaying whilst still attached to my body.

"It came to me this epiphany that I could break the bones because my arm was caught so tightly."

And so Ralston acted, 'slamming' his body into the opposite wall while grabbing the 'backside of the boulder'.

"Pumping my body over it until finally that bottom bone snapped," he continued.

But then came the task of cutting himself free of the part of the limb trapped and also broken.

Ralston's story inspired the movie 127 Hours. (ILIR BAJRAKTARI/Patrick McMullan/Getty Images)

Ralston said he 'just dove into' the surgical procedure, starting with 'st[icking] the knife down' in an area near his thumb.

Thankfully, he 'couldn't feel it' however, when the knife entered about half-an-inch into his flesh Ralston began to hear a 'hissing sound'.

He continued: "The decomposition gas was releasing from inside my arm, my hand, where they'd been building up as my arm [and] hand had been decomposing over those five days."

Ralston recalled 'bleeding down the wall' having to severe arteries and ending up needing to take 'the plier side of the knife' he had and use it to 'grab and twist and rip until the tendon gave way'.

"And then I was looking at the nerve, this little strand of spaghetti running through my arm and I had to take the nerve and pry it up," he added, noting it felt like 'fire'.

Miraculously, Ralston survived the trauma and then scaled a whopping 65ft cliff to get out of the canyon, later found by three Dutch tourists and picked up by a search-and-rescue helicopter.

He has since gone on to write a book about his experiences, the incident also inspiring a film - 127 Hours (2011) - in which Ralston is played by James Franco and he also continued mountaineering despite the ordeal.