After putting their heads together, the team came up with a biomaterial that closely mimics the natural tissue found inside intervertebral discs. The nucleus of a spinal disc contains mostly water, and keeping those discs hydrated is the key to maintaining a normal disc height and spinal support. If a disc becomes injured or wears thin over time, it may lose the ability to stay hydrated which leads to serious pain and potentially osteoarthritis and spinal stenosis. There are some other minimally invasive, non-surgical treatment options which involve injecting material into the disc, but these procedures often require full or partial nucleotomy and use implants which may not fully restore disc flexibility. The hydrogel from the Aston-Oxford-Keele team,however, requires no nucleotomy, and physicians can inject the biomaterial directly into the disc. According to the researchers, this material could reduce some spinal surgery to a day procedure as well as offer a solution to the large number of patients deemed otherwise unsuitable for spinal surgery. The Aston Biomaterials Research Unit first worked with artificial tissues in a completely different area—artificial corneas, the surface of contact lenses and chronic wound areas.
“This was a great stepping stone,” says Professor Tighe, “that made us realize there are no long term biocompatibility problems or even short term biocompatibility problems in putting this material in contact with real tissue because the body uses very similar approaches to keep the tissue hydrated." Think of the way the cornea remains hydrated during the day and the way that the disk recovers so well overnight — the underlying mechanism remains exactly the same. And that is what we sought to mimic.
The first chunk of funding for the research came from the UK government’s Engineering and Physical Sciences Research Council (EPSRC). The team received about £750 thousand in grant money which was split evenly among the three universities. As for the initial tests of the biomaterial, according to Professor Tighe, “What we have done and have been doing continuously from the beginning is in vitro mechanical testing on various spine models using cow segments and sheep spine. We have done quite a lot of in vitro testing which has been all very successful.” “Following that initial grant,” explains Professor Tighe, “which was really a three-year grant, we at Aston applied for a one-year follow-up grant from the research council in order to optimize the functioning of the material and to look at the commercial exploitation of the material. And that 12-month period is just about up now and we're writing up our research and results. So I think all of the fundamental work is done, and we feel that's it's now ready to go into the hands of people who will exploit it more widely than we are able to.” According to Darian Brookes, the team’s Business Development Manager, “We have some contacts with firms, mostly in the US, and we are in the extremely early phases of what will hopefully lead to actual testing in humans.” And the research team’s recent Spine Technology Award might just help this project get the attention of potential partners. Professor Tighe adds: "This is a very welcome recognition, especially because we hadn’t really set out for great recognition. It's the first time we've put our head above the parapet, and it's good to have it in such a prestigious area of awards."