Better bonds with bone

Surgeons often only offer replacement joints such as hips to older patients as the growth of fibrous tissue around them can lead to failure within 15 years of fitting and revision surgery is complex. Introducing a degree of randomness to a regular pattern on the titanium surfaces of prosthetic joints could increase their life span by letting bone tissue grow into them instead.

Dr Matt Dalby, lecturer in cell engineering at

, is leading research combining stem-cell biology and material science with the aim of encouraging bone to grow onto the implant.

'Currently, the problems are twofold,' he said. 'You get the wrong tissue type forming on the bone, and the modulus [stiffness] of the material is so much higher than that of bone you don't get bending of the implant with the bone.'

Dalby previously carried out research with a fabricator at Glasgow, which showed that bone marrow stem cells could be encouraged to develop into bone by creating nanoscale topography — surface roughness — on polymers, and wanted to apply the same idea to titanium.