The Tough Mudder is no ordinary run. It's a test of endurance that will challenge every fiber of your being, but that's not stopping a Rockford woman from participating in it - even if she only has one leg.

It was during the summer of 2011 when Amy Kauffman's life changed forever.

"I started to feel sharp pain in my right foot, and it progressively kept getting worse," said Kauffman, who is a mother of six. "I ended up going to see a doctor and he immediately said I needed to get an MRI."

Kauffman was diagnosed with Arteriovenous Malformation, which is a vascular anomaly, causing an abnormal connection between the arteries and veins in her foot.

"I was put through a battery of tests, but ultimately is was determined that my foot had to be amputated," said Kauffman. "Before that happened, I had to wait for my foot to die."

"The burning, stabbing pain was excruciating," she said. "I've never cried out to God more than during those weeks."

Kauffman had her right foot removed in August 2013. She began grueling therapy at Mary Free Bed Rehabilitation Hospital in Grand Rapids, Michigan.

Two years later , her problems persisted and Amy decided to have her right leg amputated just below her knee.

"I had to start the rehabilitation process all over again," said Kauffman. "That was a dark and depressing time for me."

As her rehab continued through 2016, she decided to start running again.

"I was a runner in high school, and wasn't willing to let this prevent me from trying to do that again," said Kauffman.

Amy's orthotist and prosthetist at Mary Free Bed, Katie Johnson, began tailoring her therapy to involve more running.

"With her prosthetic on, we had Amy do some slow strides on the treadmill," said Johnson. "She stuck with it last fall, and now that's paid off."

Amy says she could barely walk long distances 7 months ago, but after continuing her rehab with Katie, she's now able to run 6 miles.

"Going from where I was last fall to where I am now is truly miraculous," said Kauffman.

Amy has run in several 5Ks so far in 2017, including the Fifth Third River Bank Run 5K last month. When Katie Johnson heard of all that Amy was able to do, she suggested that she join the Mary Free Bed team that is heading down to Brooklyn, Michigan on Sunday, June 4 to participate in the "Tough Mudder" run.

"She immediately said she'd do it after I asked her," said Johnson.

Amy will be one of 8 Mary Free Bed patients who will be facing the arduous challenges of running through mud, climbing high walls and swimming - and these are just a few of the elements they'll face along this endurance obstacle course, which will be constructed on the infield at Michigan International Speedway.

"Two of my kids will be doing it with me," added Kauffman. "And so will my prosthetist."

Katie Johnson, who has been by Amy's side through years of rehabilitation, will be by her side every step of the way through the "Tough Mudder" on Sunday.

"I'm so excited to be able to be there and watch her do this," said Johnson. "Who knows, maybe I'll be the one struggling and she'll have to pull me over the wall, instead of the other way around."

Even though she's only doing half of the obstacles along the Tough Mudder course Sunday, she's certain she will conquer them all and finish.

"I can do this," Kauffman said with conviction. "I think when you go through something like this, and you're able to look back and see accomplishment, and see that you're going beyond where you were at certain points along the journey, that can mean everything.

"It certainly means everything to me."

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