HOUSTON (KTRK) --A Houston nurse has turned a traumatic moment into triumph and is now using it to help his patients and inspire others around Houston.
"I was diagnosed with bone cancer osteosarcoma at the age of 14," said Mark Barr.
Doctors told Barr his cancer was in his knee and spreading. After months in the hospital and undergoing chemotherapy, doctors decided they had to amputate his knee to cut out the cancer.
"My only concern was, was I going to be able to do sports," said Barr. "When I had my leg amputated, when I woke up in the recovery room my nurse was actually an amputee herself."
It was that nurse, in that moment that gave Barr something that he would keep forever, hope.
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"I explain her as being like an angel. Cause what are the chances of that person being there when I needed her the most," said Barr.
Barr eventually beat his battle with cancer, and eventually became a nurse. This past January, a moment presented itself to pay it forward.
"I got T-boned by a truck, and I was driving my motorcycle," said Andrew Medrano. "The pain was terrible."
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The worst of Medrano's injuries were to his leg. It was mangled and crushed in the accident.
"It was damaged to the point where an amputation was necessary, medically," said Barr.
"It feels like there's no point in living anymore," said Medrano.
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It was then, Barr intervened, lifting his pant leg to reveal his secret, the same way that nurse years earlier did for him.
"It was a shocker. I had no idea. I would've never guessed it," said Medrano.
And Medrano would have never guessed Barr's other big secret, and neither would you. Barr is a four-time para-athlete national champion and a two time US Paralympian, headed to Rio this Summer.
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"Seeing him pushing it to the limits like that, it really made me think that everything can be just normal again," said Medrano.
Last week, Medrano took a step to getting back to normal. Barr was right there by Medrano's side as he got fitted for his prosthetic leg and took his first steps.
"It's really rewarding for me to be able to have that experience with them," said Barr.
Barr showing all of us, it's not what happens to us, it's what you do with it that makes all the difference. Barr is also the vice president of a non-profit group called Catapult. The group helps disabled individuals over adversity and into the world of endurance sports and athletics.