Struggling with mobility is troublesome under any circumstance, but for 56-year-old Mary Cooper, who waits tables and is helping raise some of her grandchildren, moving was incredibly difficult.

For years, she battled severe pain every time she walked. Arthritis in her hip was to blame. The condition had gotten progressively worse following a car accident in her teens.

“It kept getting worse and worse,” said Cooper of Millvale. “I didn’t know what to do.”

As a full-time waitress, she did not have health insurance but made too much money to qualify for a Medicaid program. Serving tables at Reichhold’s Cafe on Route 8 in Penn Township became excruciating in the last year or two.

She said customers often assisted her at the counter so she wouldn’t have to come to the table as often.

“It was to the point where I wasn’t able to carry things anymore,” she said.

She continued her job because she needed the money and didn’t have anywhere else to go.

Meanwhile, Tom Muzzonigro, an orthopedic surgeon at Butler Memorial Hospital, often came into the restaurant and ordered the same takeout breakfast: a fried egg with cheese, two pieces of bacon and wheat toast. She had served him at Reichhold’s Cafe and the former Rocky’s Cafe in Gibsonia for more than a decade.

“I knew what he ate, but I didn’t know his name,” she said.

Known by many of his patients and co-workers as Dr. Muzzy, Muzzonigro took note of her worsening condition. He told her who he was and urged her to apply to the Operation Walk Pittsburgh program to see if she would qualify for a free hip replacement.

The program helps a handful of people in the region receive free hip or knee replacements which they otherwise couldn’t afford.

Cooper was one of two patients at Butler Memorial Hospital last month who had the surgery under the program. Three other people had surgeries at Magee Women’s Hospital in Pittsburgh during 2013.

Nationally, more than 250 hip and knee replacement surgeries were performed through the program this year.

“She was the rare person they talk about, who is working, but has no meaningful access to health care,” Muzzonigro said.

Out-of-pocket costs, the doctors, the hip replacement surgery itself and physical therapy afterward, could have cost an estimated $35,000. But at Operation Walk, which has regional affiliations throughout the United States and Canada, doctors and all involved do the work at no cost.

The program originally had doctors assist patients in developing countries, but it has begun operating on those who need help domestically.

“You really get to do what you were trained to do, what you love to do, and you do it for people who normally don’t have access to care, who really deserve it,” Muzzonigro said.

He operated on Cooper, and said her situation was particularly dire.

While she was still able to walk with a limp before surgery, that wouldn’t have been the case for long, he said. Her hip joint likely would have collapsed within the next year, leaving her to rely on a walker or wheelchair and in a lot of pain. Luckily for her, things did not progress to that point.

“I’m surprised I did it as long as I did,” she said.

Not only does Cooper get to celebrate the holidays with “a new lease on life,” but she hopes to enjoy more time with her grandchildren. In particular, she’s looking forward to doing things she had to pass up on for a while, such as hiking in the woods and swimming.

“This summer,” she said, “Grandma’s hoping to be able to do that again.”

For information about the program, go to www.operationwalkpgh.org.