The articular cartilage, which forms the outer, smooth surface of the ends of bones, is often damaged during injuries. These osteochondral injuries are exceedingly common in athletes, often leading to an unexpected end of a sports career.
Researchers at Rice University have now developed a way to 3D print scaffolds on top of which bone and osteochondral tissues can be grown. The technique would allow orthopedic surgeons to request the production of bespoke scaffolds that would perfectly fit the damage done by every unique injury, and that can quickly be taken over by the patient’s own cells.
One major problem with mimicking osteochondral tissue is that it’s essentially a hybrid between hard bone and cartilage. The closer it is to the ends of the bone, the more cartilage-like it is, the farther away, the harder it is. So there needs to be a gradient in the nature of the tissue and the Rice team developed a way to recreate this gradient, with different porosity levels and different sized pores.
The scaffolds tougher at one end and softer at another, and the parameters of this change can also be pre-programmed when designing a particular implant. All the implants, though, pop right back to their original shape after being squeezed, but at different rates, so there’s more work to be done to be able to make sure that each implant has the exact mechanical properties that will be required of it.