Why expert believes Princess Diana could have survived her 'incredibly rare' fatal injury

Princess Diana could have survived her 'incredibly rare' fatal injury, according to a forensic pathologist.

It's been more than 28 years since the world mourned the death of the People's Princess in a tragic car accident.

On August 31, 1997, the 36-year-old and her partner, Dodi Fayed, were trying to flee paparazzi in Paris when the crash occurred.

It is claimed that Princess Diana's chauffeur, Henri Paul, had lost control of the vehicle at the entrance to the Pont de l'Alma underpass and struck another car before swerving across the tunnel into a column at around 65 mph.

The crash claimed the lives of all three, with only Dodi's bodyguard, Trevor Rees-Jones, surviving the wreckage. Diana tragically went into cardiac arrest and died of internal bleeding stemming from major chest and lung injuries.

Now, however, renowned forensic pathologist Dr. Richard Shepherd has claimed she could've lived 'if only' a few life-saving measures before and in the immediate aftermath of the crash had happened.

The crash claimed the lives of three who were travelling in the vehicle in 1997 (JACK GUEZ/AFP via Getty Images)

After examining the evidence in the case, the pathologist said in his book Unnatural Causes, which is due to come out April 18, that her specific injury, a tiny tear in a vein in one of her lungs, was 'so rare' he'd never seen it before in his career.

"Diana's was a very small injury but in the wrong place," he said.

However, the doc is keen to put conspiracy theories to bed, explaining how her death is 'indisputable' from the injury she sustained.

But, he said that Princess Diana's death stands as a 'classic example' of an 'is only' case, stressing that she probably would've avoided the horrific injury 'if only' she'd been wearing a seatbelt.

Dr Shepherd wrote: "Had she been restrained, she would probably have appeared in public two days later with a black eye, perhaps a bit breathless from the fractured ribs and with a broken arm in a sling."

Princess Diana could've survived if she'd done this one thing (Tim Graham Photo Library via Getty Images)

Mr. Rees-Jones, the sole survivor, was the only passenger buckled up in the car, according to People, which likely helped to absorb some of the force of Diana's collision into the back of his seat.

Dr Shepherd added that another 'if only' comes down to how she was sitting, as had she hit his seat at a slightly different angle or at a slower speed, it's possible she could've survived.

The other 'if only' comes down to her hospital treatment, as Diana wasn't immediately put in an ambulance as she appeared responsive.

In reality, however, her ruptured vein was bleeding into her chest.

A first responder on the scene, firefighter Xavier Gourmelon, confirmed that he was unaware that Diana suffered 'serious internal injuries.'

The four travellers in the car moments before the fatal crash (Jacques Langevin/scottbaker-inquests.gov.uk via Getty Images)

"To be honest, I thought she would live. As far as I knew when she was in the ambulance she was alive and I expected her to live," he told The Sun after revealing Diana's tragic last words to him.

A 2004 police inquiry investigated whether there were any suspicious circumstances or if there were any reasons to doubt that the deaths were from an accident, with the inquiry concluding that it was a 'tragic accident'.

Dr Shepherd agreed with the inquiry's conclusion, adding in his book: "The pathology of her death is, I believe, indisputable. But around that tiny, fatal tear in a pulmonary vein are woven many other facts, some of which are sufficiently opaque to allow a multitude of theories to blossom."