Dem bones, dem bones, dem artificial bones

A joint team of researchers from the University of Cambridge and the Massachusetts Institute of Technology has begun work on developing better artificial bone to replace damaged and worn-out human bones.

The researchers are setting up an Interdisciplinary Research Cluster into Biomaterials and Tissue Engineering, which will receive £2 million of funding over three years from the Cambridge-MIT Institute.

The research team is working on developing a new kind of bone that will be readily accepted by the human body. The new bone will be made using a laboratory equivalent of human bone mineral (hydroxyapatite), and other new materials.

The technology involved could also lead to new approaches to the repair of damaged organs, like the pancreas and the liver. Currently, many artificial hips and knees have to be replaced because the patient’s own bone ‘resorbs’ and disappears from around the implant. There is also an unsatisfied demand for effective spinal implants, to replace worn-out vertebrae.

The research team spans a range of disciplines from materials science, physics and engineering to medicine. At MIT, it involves pioneers in the fields of tissue engineering, and artificial skin, and is led by Professor Lorna Gibson, Matoula Salapatas Professor of Materials Science and Engineering. The Cambridge team is led by William Bonfield, Professor of Medical Materials, alongside a team of international experts in bone replacement and biomaterial innovation.

Professor Bonfield explains that current artificial bone implants may not have a long lifetime in the body because they are made of materials, such as stainless steel or engineering plastic, that are dissimilar to human bone.

‘The aim of this new research project is to produce artificial bone that is bioactive, i.e. mechanically and biologically compatible with the human body.’

To this end, the Cambridge-MIT team is developing ‘scaffolds’ of new bone material which is porous, so that a blood supply can flow through it, and so that human tissue can grow into it.

Professor Bonfield adds: ‘The key to making this process successful is making it happen fast. All the evidence suggests that the earlier an implant is integrated into the body, the better the long-term outcome. Our aim is to develop a system whereby this integration will start within one day of our artificial bone being implanted.’

Professor Bonfield is optimistic that new bone materials will be in clinical trials when the research project ends in three years time. He says: ‘We’re excited about this project because it could be of real benefit for patients. At the moment, some artificial bone implants are unsuitable for younger patients, because their bone resorbs so quickly that the replacement is not viable. A new generation of artificial bone, and one that was absorbed into their own bone and tissue, would be much better.’