A hip stem developed 50 years ago has now been implanted in more than two million patients.
The Exeter hip stem was a collaboration between NHS surgeon Professor Robin Ling and University of Exeter engineer Dr Clive Lee.
Their stem was revolutionary as it did not have a collar between the neck and stem of the implant like previous designs.
Dr Lee said going back to basics "worked out very well indeed".
He added: "I started out not really knowing what a total hip replacement should look like - that was probably a huge advantage."
The groundbreaking design overcame a problem of previous hip implants - that they eventually became slightly loose.
Since the first implant on 27 November 1970, the Exeter hip stem has been implanted globally in more than two million patients, with one million happening in the last 10 years alone.
Ballerina Rachel Merga was devastated she might never be able to do the splits again following her hip replacement.
But three years after receiving the Exeter hip, she can execute the move and many others.
She said: "I delayed it for as long as possible, but I was in constant pain. I knew it was the only option."
Ms Merga, who lived in Honiton, Devon when she had the operation, said she is now "comfortable" in a professional-level dance class.
"I really feel ready to get on to the stage again," she said. "I had no idea if that would ever be possible again."
Another person benefitting from the stem is stuntman Steve Colley from the Isle of Man.
He is now more agile than ever after "decades of agony" thanks to two Exeter hips that were fitted in 2018.
"I was starting to think my career could be over," he said.
After the operation in Exeter, Mr Colley said the improvement to his movements was "incredible".
"Even now, every day I notice my range of movement is a little bit better," he said. "I'm riding better than ever before."