Hoping to lessen the scourge of diabetes, researchers and engineers at the University of Arizona are studying what may be the most expensive pair of socks in the world.
The SmartSox, which could help prevent amputation in diabetics, use fiber optics - the same system of light transmission currently used in many settings, such as nuclear plants and airplanes.
The socks cost upwards of $70,000, but researchers believe that expense just might save lives.
The UA Department of Surgery's Southern Arizona Limb Salvage Alliance is one of three partners that received more than $2 million in research grants from the Qatar National Research Fund to conduct a three-year study on the state-of-the-art socks, which are embedded with sensors that can detect the early signs of foot ulcers that may lead to amputation or death.
The other partners in the project are the Qatar-based Hamad Medical Corp. and the UA-based Interdisciplinary Consortium on Advancement Motion Performance, also known as iCAMP.
Diabetes kills more people every year than breast cancer and AIDS combined. Part of the reason is that limb amputation often accompanies the disease, and shortens diabetics' lives.
That's where the SmartSox come in. Physicians and researchers hope they will prevent the diabetic pressure sores that often form silently and painlessly until it's too late.
"We are seeing an exciting merger happening in the health-care world between consumer electronics and medical gadgetry," said Dr. David G. Armstrong, a podiatric surgeon and director of the UA limb salvage alliance. "This has implications not just with feet, but everywhere. We can take a sample of someone's life and get a good picture. This is the measure of quality of life that we have been after forever."
From the outside, the SmartSox appear normal, with gray fabric and red polka dots on the sole of the feet that indicate the major pressure points. Two clear fibers protrude out of the sock, each embedded with microscopic sensors.
The socks detect when the patient experiences excessive pressure, heat or an odd joint angle of the big toe - all occurrences that with repetition can cause foot ulcers, said Bijan Najafi, an internationally recognized UA biomedical engineer and director of iCAMP.
"With fiber optics, light is the only thing going through the socks, and when there is a deformity or stress on the fiber, the length of light is changed. We measure these lengths, and it tells us changes in temperature, pressure or joint angle of the foot," he said.
Pearl Badman, 62, is a regular at the UA's limb salvage clinic and is expected to be one of the first to try the SmartSox once they are approved for a clinical setting. Had the SmartSox been in use back in 2010, the toes on her right foot might have been saved.
Doctors diagnosed her with peripheral neuropathy when she developed her first wound and then Type 2 diabetes in 2010. Since then, she's had seven surgeries on her right foot.
Badman had surgery two days before Christmas in 2010 to remove her first two toes and then in 2012 the rest were removed. That is not uncommon. More than half of all foot ulcers become infected, and one in five will require an amputation, according to a 2006 study published in the journal Diabetes Care.
"You don't realize how important your toes are for balance until you lose them. When they took the cast off, that's when I realized my toes were gone. That's when it hit me," Badman said.
The high-tech socks are about to go into clinical trials, when researchers will recruit 120 patients who have been diagnosed with diabetes and peripheral neuropathy as well as with a prior history of a foot ulcer to participate in the three-year study. The recruitment process, which will begin in April, could take up to two years, according to Najafi.
"We have 26 million people with diabetes in the U.S. and 80 million with pre-diabetes, and over time they will lose the gift of pain, the most significant and consistent symptom," Armstrong said.
"Most people don't consider pain a gift, but once the important feedback mechanism is lost, diabetics wear holes into their feet like the average person might wear holes in their socks or shoes."
Armstrong and his team in the UA Department of Surgery witness the effects of diabetes-induced ulcers and amputation daily.
"It makes them feel less than themselves, yet ulcers and amputation are preventable," Armstrong said. "People's feet are really killing them."
In the last 10 years, the number of adults in Arizona with Type 2 diabetes has more than doubled, according to the Arizona Department of Health Services.
More than 9 percent of the state has been diagnosed with diabetes, and more than 20 percent of adults have pre-diabetes. Arizona is ranked 10th in the nation for obesity. That and inactivity are risk factors for developing Type 2 diabetes.
Those percentages work out to 380,000 Arizonans living with diabetes, and if it were its own city, it would be the fourth-largest in the state.
The feet are at greatest risk for developing diabetic ulcers or wounds. More than 60 percent of diabetics will develop mild to severe nerve damage farthest from the central nervous system, the American Diabetes Association says.
"The feet and legs are at the end of this anatomic peninsula, and within medicine we largely ignore that walking upright and the ability to move and feel is something that has made us human for the last 2 million years," Armstrong says.
Once chosen for the study, each person will be asked to take about 20 steps in the socks. Researchers will conduct a one-year follow-up study on the patients.
Based on the current literature, along with patient history and parameters measured by the socks, researchers will create a statistical model that can be assessed for predictive power of foot ulcers and amputation, Najafi said.
Type 2 Diabetes
Type 2 diabetes is the most common form of diabetes, and it develops when the body does not produce enough insulin or the body does not use the insulin correctly. The body breaks down sugars and starches from food into glucose. Insulin retrieves the glucose from the blood and transports it to cells for fuel and energy. When insulin stops functioning, the glucose, or the sugars, build up in the blood, producing hyperglycemia.
The buildup of glucose in the bloodstream can manifest in all types of complications. It can lead to heart problems, stroke, high blood pressure, blindness, kidney failure, neuropathy and amputation.
By 2050, one in three U.S. adults will have diabetes at the current diagnosis rate, the U.S. Centers for Disease Control and Prevention says. Reports show that diagnosis combined with direct medical costs from diabetes cost the nation $254 billion in 2011, up $71 billion from 2007.
Courtney L'Ecuyer is a University of Arizona student who is an apprentice at the Star. Contact her at 573-4117 or at firstname.lastname@example.org