Silk screws

Silk is renowned for its strength, softness and beauty. It now appears that it have a very practical use too. Scientists are testing silk screws and other connectors as a new way to mend bones.

These screws are made entirely from silk, and have many benefits, chief among them being that the silk is slowly broken down in the body. It is also not affected by X-rays or airport security, and doesn’t cause sensitivity to cold.

So far, the screws have been tested on rodents, but the results are encouraging. The team, from Tufts University (Massachusetts), and led by Dr David Kaplan, sees the silk’s potential for any usage that requires nothing left in the body. More exactly, fibroin is used, which is the tough centre-strand of silk. It is this fibre that gives silk its strength.

Also of interest is the low stiffness of silk. Surprisingly, this is similar to that of bone, mean it could well be used for many more bio-engineering uses.

Using specially designed moulds, the researchers made screws with medical grade silk. This can be machine-cut to specific sizes.

Eventually, the idea could lead to replacing the titanium or steel screws, plates and wires commonly used in surgery. Because they naturally disintegrate in time, they don’t need to be surgically removed. As the parts dissolve, the bones have time to grow back, meaning a smoother transition from artificial to natural.

Meanwhile, there are many more possible applications of silk. Fiorenzo Omenetto, also with the Tufts materials’ lab, has a great TED talk in which he discusses the possible uses of silk, from medicine to light transmission. You can watch the video here.


More on the research via Nature Communications.