Regenerative medicine for the spine
When we think of mechanical forces, we tend to think of machines. But consider this: when you bend from the waist to pick up something like a medium-sized box, you generate about 3 megapascals of pressure in your spine—about the same pressure a submarine encounters at a depth of 300 metres. And your intervertebral discs (the flexible parts of the spine between the vertebrae) bear the brunt of that pressure. It's no wonder disc-related back pain is a common and debilitating disorder.
It's also an engineering problem for AHFMR Scholar Dr. Christopher Hunter, a biomedical engineer at the University of Calgary. "I'm interested in biomechanics and regenerative medicine for the spine. I study how mechanical forces influence disease and health in our bodies." Dr. Hunter began his research career working with cartilage but has since focussed on tissue engineering technologies to repair or replace intervertebral discs.
One major project involves repairing herniated discs. When the fibrous outer layer of a disc herniates (bulges out), it can tear and the gel inside the disc can leak out. Dr. Hunter has developed a patch to plug the tear that is made of biologically derived materials. Laboratory test results are promising and Dr. Hunter hopes to move the patch to clinical trials within five years.
Another facet of his research involves testing the new generation of bone cements. Unlike conventional bone cements that are inert and are used to fill places where bone has been lost, the new cements become a porous structure into which bone can grow. The cement is reabsorbed by the body over time. "After three years, the bone has regrown and you can't tell there was ever any cement," says Dr. Hunter. "You can see a day when a lot of casting and surgery won't be needed—physicians will just glue bones back together."
But in the meantime, more information is required on the effects of these new cements on treated tissues, if they are to come into widespread use. "That's the kind of testing we do in my lab," says Dr. Hunter.
"The work on bone cement was pure serendipity. A colleague of mine, who is a surgeon, was interested in getting more scientific data on the cement. It snowballed from there. If you are willing to go beyond your comfort zone, it's amazing how many places engineering will take you."