Jake Quickenden sustained a horrific injury during Celebrity SAS: Who Dares Wins and was rushed to hospital after his tendons were torn off the bone.
The 33-year-old reality TV presenter was forced to withdraw from the competition in the wake of the accident, which will feature in Sunday night's episode of the extreme adventure show.
Quickenden told The Sun he sustained the serious injury to his chest while trying to pull himself out of the sea and on to a boat.
After withdrawing from the competition, he had to undergo surgery in order to repair the damage done during the accident.
"I ruptured my pec muscle and my bicep, so the tendons were torn straight off the bone," he said.
Watch: Kerry Katona talks about therapeutic element of Who Dares Wins
The star added: "I had to have them stretched back to my shoulder. I have got four pins in my shoulder now where they are all pinned back into place.
"After the operation, I had no feeling in my arm at all for 48 hours. It was like my arm was totally gone."
Quickenden said it was a "nightmare" to have to withdraw from the show, which has already seen Kerry Katona and Ulrika Jonsson depart, and has vowed to return for the next series.
Meanwhile, former Loose Women panellist Saira Khan sustained scarring during filming, while footballer Kieron Dyer was treated for a collapsed lung.
Quickenden added: "It hurt, but I wasn’t bothered about the pain. I was just so annoyed that it meant my time was done and my journey was finished. I’m just absolutely devastated."
Celebrity SAS: Who Dares Wins sees famous faces put through their paces in a training course designed to mimic elements of the selection process for UK Special Forces.
The first series was won by footballer Wayne Bridge, while the second saw Rudimental DJ Locksmith and Paralympic athlete Lauren Steadman complete the course.
Other contestants in the current series include Love Island star Wes Nelson, singer Alexandra Burke, Geordie Shore cast member Vicky Pattison and Olympic rower James Cracknell.
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The series is the last to feature instructor Ant Middleton, who was dismissed by Channel 4 earlier this year over his "personal conduct" in the wake of numerous controversial comments.
He has since claimed the "woke patrol" have transformed the programme into "a half-scripted reality show".
Watch: Ant Middleton insists his career is far from over