Bone Measure
updated:
Paul Hansma's face lights up when he talks about what his latest research might mean for people who suffer after breaking their hips or other bones that become more and more brittle as they age. Statistics show that a woman is more likely to die in the next year after a hip fracture than if she's had a heart attack.
Hansma, a professor of physics at UC Santa Barbara who has spent much of the past 20 years developing Atomic Force Microscopes, has focused on biophysical research and the study of human bones. His renowned bone tissue research has led him to what he believes will be a significant step in the study of biomaterials: development of a new medical diagnostic tool - the Reference Point Indentation (RPI) instrument.
Hansma is a co-author of a new study published in the Journal of Bone and Mineral Research. In the study, "Microindentation for in vivo Measurement of Bone Tissue Mechanical Properties in Humans," Hansma and his co-authors say they have validated the
"This is a revolutionary breakthrough," Hansma said of the
The study documents the first clinical trials of the
"The properties of bone materials are an important part of fracture risk," Hansma said. "In normal, everyday life, you wonder about whether something is going to break or not. It depends. How big is it? How thick is it? Is it made of balsa wood, or walnut? In the field of bone fracture risk, there has not been any instrument that can measure the material properties of bone relative to fracture risk, so it's been ignored."
Conventional measurement is currently done for bone mineral density. It's done with X-rays, called DEXA (dual energy X-ray absorptiometry). "This is a measure of how much bone you have," Hansma said. "As people age, they lose bone. This bone loss can be monitored with DEXA. If you've lost a certain amount, you'll typically be prescribed drugs like Fosamax or Boniva. They help the bones get bigger, help mitigate bone loss and, in some cases, rebuild bone. It's a $6 billion market right now, growing at 25 percent per year. All they're doing is dealing with bone quantity. They're dealing with half the problem."
What's been missing is a way to measure bone quality. Using the
All clinical trials have taken place in
"What you can see from the tests is that everyone whose bone was easily fractured by the
The ability to do these tests on live patients was a key factor in the success of the research. "You can't cut a section out of a lot of peoples' bones, test them with a conventional mechanical testing device, and then follow the people for 10 years to see who has fractures," Hansma said. "A small community of scientists has been working on bone material properties, but there has been a lack of any kind of connection to clinical trials. That's what this paper represents: a bridge between the people who have been working on bone materials properties, and the physicians who are needing to make decisions about treating patients."
So far, the only site approved for clinical trials is in
A new
Hansma is chief scientific officer for Active Life, which was founded by two UCSB graduates, Davis Brimer and Alex Proctor. "This company was started by two students without deep pockets," Hansma said. "They have been funded to date by friends and family, and are now receiving fund from visionary investors who see the promise in this technology. They've sold nine instruments, including one to an equine veterinarian who believes the technology can be used to diagnose and treat racehorses. Active Life doesn't yet have the resources to fund clinical trials, or to give instruments to people who can do clinical trials. That's why we're grateful to Adolfo. He funded the trials himself. With the results of his work in
Hansma's next project will be a collaboration with UCSB Chancellor Henry T. Yang, who's also a professor of engineering, and Srinivasan Chandrasekar, a professor of industrial and materials engineering at
Co-authors with Hansma on the