Bone cancer often means amputation for patients. If they are lucky, surgeons can remove the tumour and insert a prosthesis into the cavity that contained the bone. But the prosthesis may not fit properly and can loosen over time. This could lead to further pain and costs for patients who have already suffered both.
Fortunately, new research published in Physics Procedia opens the door to implants that are custom-made right in theatre. Prosthetic bones can be made using additive manufacture, more commonly known as 3D printing. This involves building the prosthesis one very thin layer at a time.
Milan Brandt and his colleagues at the Centre for Additive Manufacturing at RMIT University in Melbourne, Australia, have developed a technique for designing, 3D-printing and fitting personalised bone implants within a single operation. They rapidly image the cavity with a CT scan and 3D print a lattice that perfectly fits its shape. “Our novel tools require only a fraction of the time used by current prosthesis design methods,” Brandt says.
Currently, scientists and doctors 3D-print prosthetic bones using plastic and hydroxyapatite – a mineral found in natural bone. Brandt’s structures, however, are made from titanium – a light, durable and rust-free metal. The researchers fused layers of powdered titanium with a laser, a technique that operators can use to create any shape.
Brandt and his co-workers tested their procedure on a model bone made from plastic, which was as strong as real bone. They removed about 40 per cent of this fake bone to mimic a surgical operation and filled it with a 3D-printed lattice.