Delving into the pain of osteoarthritis

PITTSBURGH – Her foot pain began 15 years ago, leading to a 2002 diagnosis of osteoarthritis, which left her limping and unable to walk for extended periods of time.

And it progressively worsened.

In time, Deborah Cole Thomas, 60, of Plum, Pa., would undergo surgeries to fuse joints in both feet along with a left-ankle replacement, all from the wear-and-tear form of arthritis. She endured shoulder pain and more recent problems with right-knee pain, which she likens to a knife stab.

Round-the-clock pain medications are a must.

“I try not to let it affect me,” Thomas said, noting that her husband, Llewellyn, 82, has had both arthritic knees replaced. “It drives me to keep moving. I watched my mom give up, and her hands became so crippled she had to be fed.”

Thomas, now retired, worked as a Westinghouse computer engineer, spending hours at a desk that made her “feel like the Tin Man in ‘The Wizard of Oz.’ “ She’d stand and struggle to flex stiffened joints.

In coming years, she faces further surgeries, including knee-replacement surgery. But she’s still walking, with the goal of 10,000 steps a day and an average of about 7,000.

She also can’t run and isn’t allowed to jump. Doctor’s orders. But she works around those limitations.

“There’s always something I can do just to keep moving.”

While people with osteoarthritis struggle to move, there’s plenty of movement in research as scientists work through the biological puzzle of osteoarthritis to come up with potential treatments.

A University of Pittsburgh research team, led by Rocky S. Tuan – professor and executive vice chairman of the department of orthopedic surgery and director of the Center for Cellular and Molecular Engineering – is making headway in understanding the complex stew of enzymes (histones), proteins and genes that cause osteoarthritis while identifying a potential treatment to slow the rate of cartilage destruction.

There’s further breaking news from the Tuan camp that sounds like science fiction:

His team is using a 3-D printer, which makes structures one layer at a time, to make new joints. Using a solution containing the patient’s stem cells, along with growth factors and scaffolding material, the 3-D printer constructs actual cartilage in the right shape to replace damaged cartilage.

The stem-cell solution extruded through a catheter also could be used to create new cartilage, as guided by a 3-D printer, directly onto the joint bone.

The team’s tissue-engineered joints already have shown success in large animals, raising the promise of creating replacement joints for people now dependent on plastic and metal ones. The process could be particularly useful in repairing battlefield injuries.

Tuan announced the success April 27 at the Experimental Biology 2014 scientific sessions and meeting in San Diego.

“We essentially speed up the development process by giving the cells everything they need, while creating a scaffold to give the tissue the exact shape and structure that we want,” Tuan said, adding that his team continues working to develop cartilage more closely resembling human cartilage.

“Total joint replacements involving plastic and metal joints work well, but they don’t last long enough,” Tuan said. “For someone who is 60, that’s OK. But if you are in your 30s, that’s not good because you may need revision after revision.

“We are not in position to say that it will last a lifetime. Time is the true test,” Tuan said of the tissue-engineered joints his team has created. “I can only say it’s very promising and is looking good.”

Joints, the business end of bones, include a covering made of flexible and protective cartilage to prevent damage from friction. But chronic wear and tear from overuse, traumatic injury or bone misalignment, among other factors such as obesity, promotes a biological process, not yet fully understood, that degrades cartilage.

Osteoarthritis represents 80 percent of all cases of arthritis, whose various forms plague 27 million Americans, making arthritis the nation’s major form of physical disability. The disease burden is particularly acute in the aged population, with one out of two individuals older than 65 having at least one joint affected.

There’s even more news that could advance treatments for osteoarthritis.

The Pitt team also is using tissue engineering to develop human tissue and cartilage in a laboratory dish that can be used to test the effect of drugs. The live model of human joint tissue is being heralded as the creation of “the first example of living human cartilage grown on a laboratory chip.”

For now, the engineered cartilage tissue on a computer chip will serve “as a test-bed for researchers to learn about how osteoarthritis develops” and to develop new drugs.