"There's something left for me to do," Ms Cringle said.

"I think it's hopefully for me to support others.

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"Everyone has to work out what works for them, but I can explain 'This is what worked for me'.

"I want to help people get the most out of life, help them through difficult times. Not just the physical, but emotional as well.

"I don't see triumph as overcoming tragedy, winning or being the best at something. It's about believing in yourself and having the courage and persistence to keep going forward on your journey to achieve your personal best."

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Ms Cringle's left leg had been amputated, she had developed meningitis and her life support had been turned off before she regained consciousness in hospital after the accident.

"I had a compound fracture," she said. "Another quarter of a millimetre and I would have been a paraplegic - it was that close."

She was told she wouldn't work or drive again. But she achieved her main goals of living independently, working and walking on both legs in nine months, two years and 16 years respectively.

The East Maitland resident will visit her former high school, St Joseph's College at Lochinvar, to share her story on Friday with students. Principal Patricia Hales asks alumni to speak at award ceremonies to reinforce her message that the students "can do anything".

It will be the first time Ms Cringle has spoken at a high school.

She has spent three years writing a book, which she is likely to self-publish and hopes will propel her into the speakers' circuit.

"You don't have to suffer trauma to be able to realise your true potential," she said.

"My main message is when you come across challenges in your life, choose to have a positive attitude about the situation and the patience to develop strategies to get through.

"When things happen you have to make the decision to either give up or make the most of it.

"I don't believe in defeat. Often if you think you'll be victorious you'll get there."

Ms Cringle was 26 and living in London, working as a registered nurse and playing violin for the Fulham Symphony Orchestra on the day of the accident, December 1, 1996.

She doesn't have any memory of it or the week before it, but was told it was likely her long coat had got caught on a tube train when she changed lines at Green Park station.

She said her left leg was torn off, her head was smashed like an egg shell and part of her brain was missing. What remained was partially exposed. Five discs in her back were broken and both of her lungs had collapsed and were filled with blood.

When she woke, her late mother told her the injuries were "just as intense" as what her father had suffered two decades earlier in a car crash, which led to him requiring full time care.

"I thought 'No way'," she said. "I had to get on top of it straight away. It gave me motivation that I was going to be independent, I was not going to be cared for and I was going to do this.

"I visualised where I wanted to be and I had to tell my heart it was mind over matter.

"It was one small step at a time, no large leaps. It's easy to overlook small wins, but together they make a big difference.

"I just realised things don't happen straight away and I just had to be persistent and believe in what I was capable of."

She set small goals for herself, including sitting up and holding a cup.

Ms Cringle returned to Australia in February 1997 and stayed in a brain injury unit for nine months.

She returned to most of the sports she had participated in before the accident: swimming, dressage and tennis.

She was Australia's number one female wheelchair tennis player and also tried sitting volleyball.

She used crutches for 16 years before she became the world's first person to have the bone in her amputated leg lengthened over 70 days in 2011 to allow for the insertion of an implant that connects to her bionic leg.

Ms Cringle worked at John Hunter Hospital for 14 years before moving into aged care and her current role at a doctor's surgery.

She has continued playing the violin and is in four orchestras.

"As I get older I might not have the energy to do these things, so I'm getting out there and doing as much as I can for as long as I can."

The journey hasn't been without lows.

"A lot of people doubted my capabilities," she said.

"They undermine you and make you feel you have to prove yourself.

"You need to have the strength, confidence and belief in yourself that you're not being unrealistic to have the drive to keep you moving forward."

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