A soft touch for mending broken bones

June 16, 2017 by Lea Kivivali, Swinburne University of Technology
Credit: CC0 Public Domain

Silk is an unlikely substitute for steel in any context, but for bone fractures, it may just be the perfect thing.

A Swinburne researcher has developed a mix of cocoon silk fibres and that may one day hold bones together and help heal them from the inside out.

Steel plates and bolts are often a surgeon's only tools for fixing fractured bones. The problem is that steel can block new cells from repairing the fracture. Removing the steel through further surgery can leave bones brittle.

Materials scientist, Professor Alan Lau, said this impediment was a real problem and that a replacement for was needed.

For 10 years, researchers have investigated a biodegradable polymer called PLA, already used in some food packaging, for medical implants. If PLA could pin bones together and then be gently resorbed by the body over time, bone cells could enter the fracture and heal the bone and eliminate the need for further surgery. But so far, PLA has proved too weak to reinforce bone.

Professor Lau came across part of the solution in 2007. Avian flu had broken out in his native Hong Kong and more than a million chickens were killed to stop the spread. He wondered why the chicken feathers weren't used for something. The idea of mixing animal fibres with other materials was the genesis of his breakthrough, but the fibres from feathers were difficult to purify. Lau's team found an alternative that was easier to work with: the silk from a silkworm's cocoon.

In 2008 Professor Lau's team at Hong Kong Polytechnic University combined cocoon silk fibres with PLA and found the polymer became harder. Adding around six per cent made the biodegradable polymer as strong as bone.

The scientists also found cells can grow around the material as it degrades, showing potential for use in patients.

"At this stage we have a great accomplishment," says Professor Lau. "But there's still a long way to go."

Professor Lau is now tackling the design of the right pins and screws, speculating that the material could one day be tailored for individual patients by scanning their fracture and 3-D printing a shape that fits perfectly.

He is looking for collaborators in Australia to start animal trials and eventually progress the material to patients. He is optimistic: "If we can find a partner here to continue, this material will progress very fast."

Explore further: Silk-based surgical implants could offer a better way to repair broken bones

Related Stories

Silk-based surgical implants could offer a better way to repair broken bones

March 4, 2014
When a person suffers a broken bone, treatment calls for the surgeon to insert screws and plates to help bond the broken sections and enable the fracture to heal. These "fixation devices" are usually made of metal alloys.

Repairing bone with 3-D printing

April 17, 2017
Metallic implants—widely used clinically to replace diseased or damaged bone tissue—are not biodegradable and stay in the human body until removed surgically. The implants may also have problems with corrosion and could ...

Nanofibres developed for healing bone fractures

January 18, 2017
In the future, it may be possible to use nanofibres to improve the attachment of bone implants, or the fibres may be used directly to scaffold bone regeneration. This would aid the healing of fractures and may enable the ...

Recommended for you

Deep space radiation treatment reboots brain's immune system

May 21, 2018
Planning a trip to Mars? You'll want to remember your anti-radiation pills.

Receptor proteins that respond to nicotine may help fat cells burn energy

May 21, 2018
The same proteins that moderate nicotine dependence in the brain may be involved in regulating metabolism by acting directly on certain types of fat cells, new research from the University of Michigan Life Sciences Institute ...

Atomic-level study reveals why rare disorder causes sudden paralysis

May 21, 2018
A rare genetic disorder in which people are suddenly overcome with profound muscle weakness is caused by a hole in a membrane protein that allows sodium ions to leak across cell membranes, researchers at the University of ...

New era for blood transfusions through genome sequencing

May 18, 2018
Most people are familiar with A, B, AB and O blood types, but there are hundreds of additional blood group "antigens" on red blood cells—substances that can trigger the body's immune response—that differ from person to ...

Robots grow mini-organs from human stem cells

May 17, 2018
An automated system that uses robots has been designed to rapidly produce human mini-organs derived from stem cells. Researchers at the University of Washington School of Medicine in Seattle developed the new system.

Scientists uncover a new face of a famous protein, SWI2/SNF2 ATPase

May 17, 2018
A team of Texas A&M and Texas A&M AgriLife Research scientists now have a deeper understanding of a large switch/sucrose non-fermentable (SWI/SNF) protein complex that plays a pivotal role in plant and human gene expression ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

michbaskett
not rated yet Jun 16, 2017
There has been an alternative to stainless steel for some years now-titanium. As far as I know it is essentially nonreactive with human tissue and doesn't inhibit tissue regrowth. Actually, there are a number of alternatives for bone repair.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.