After having surgery for a meniscus tear at a local hospital just over a year ago, David Szafranski assumed he was good to go.

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"I seemed to be doing well, but then one night it all changed," Szafranski, now 51, says. "I had a cortisone shot the night before going on vacation, and as I was packing, it felt like I had stepped on a broken lightbulb. I couldn't walk.

"I was in so much pain it was unbelievable. I couldn't walk, I couldn't sleep, I couldn't do anything, and I was miserable to be around."

After the pain became too much to bear, he felt more aggressive action was necessary.

Szafranski, who lives near Cleveland, began researching knee replacements and getting recommendations for surgeons from friends and acquaintances, which led him to Bruce Miller, M.D., M.S., associate professor of orthopaedic surgery at Michigan Medicine's MedSport program.

There, Miller performed arthroscopic surgery on Szafranski's knee. Still, he told the patient that his knee would never be as it was before the injury.

Miller recommended that his colleague Joseph Maratt, M.D., clinical assistant professor of orthopaedic surgery at the University of Michigan Comprehensive Musculoskeletal Center, perform partial knee replacement surgery.

"I was just hoping it would provide some relief," Szafranski says. "I was on crutches and couldn't walk."

Immediate relief

Szafranski woke up from the surgery and noticed a difference right away.

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"About three hours after waking up, I could tell the pain was gone," he says. "I realize I was under medication, but I could tell."

One week later, Szafranski was back to walking and "gently" riding his four-wheeler ATV.

Because of his active lifestyle before the pain and surgeries, he immediately went through therapy and hired a trainer at his gym to help him with weightlifting to gain back his strength.

But Szafranski had a much bigger goal in mind.

'This is a miracle'

Just four months after replacement surgery, Szafranski went abroad.

"I decided I wanted to go on my church's missionary trip to Brazil," he says, noting that the intent of the trip was to bring clean water to indigenous tribes along the Amazon River.

Szafranski opted to take it easy while walking up the mountains.

"I was a bit gentler than I would normally be," he explains, "but I was still able to go!"

Szafranski returned last month from a follow-up trip to the Amazon and this time was able to perform everything to his body's full capacity.

"I was carrying 100-pound sandbags up the mountains and doing everything I could normally do before my injury," he says. "I called Dr. Maratt and told him this is a miracle and I can't believe there isn't pain."

A new normal

Even with a successful surgery and improved function, Szafranski had to make some changes to his daily routine.

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"I stopped running under Dr. Maratt's orders, which was hard for me because running was my weight management for eating ice cream, which I love," he jokes.

"But I can ride my bike along Lake Erie, which I enjoy, and walk on steep inclines. I try to do at least one bike ride a week where I ride on the open road for 30 to 40 miles."

Although the thought of knee replacement surgery terrified Szafranski at first, he couldn't be happier with the decision.

"From the moment I first met Dr. Miller at U-M, I felt I was being taken care of at a high level," he says. "When he recommended Dr. Maratt so highly, it was an easy decision for me. He seemed to be on the cutting edge of accurate knee replacement surgery."

Adds Szafranski: "I felt like I had the Mercedes-Benz of medical treatments. From where I was to where I am now, that knee surgery was such a miracle. I don't know if I could have a better result."