Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Spongy material helps repair the spine

14.03.2016

Remember those colorful "grow capsules" that blossom into animal-shaped sponges in water? Using a similar idea, scientists have developed biodegradable polymer grafts that, when surgically placed in damaged vertebrae, should grow to be just the right size and shape to fix the spinal column.

The researchers present their work today at the 251st National Meeting & Exposition of the American Chemical Society (ACS). ACS, the world's largest scientific society, is holding the meeting here through Thursday. It features more than 12,500 presentations on a wide range of science topics. A brand-new video on the research is available at http://bit.ly/ACSBone.


A polymer bone graft (held above in the top gloved hand) can expand in the body to just the right size to replace excised spinal tissue.

Photo credit: Lichin Lu Video credit: American Chemical Society

"The overall goal of this research is to find ways to treat people with metastatic spinal tumors," says Lichun Lu, Ph.D. "The spine is the most common site of skeletal metastases in cancer patients, but unlike current treatments, our approach is less invasive and is inexpensive."

Often, removing extensive spinal tumors requires taking out the entire bone segment and adjacent intervertebral discs from the affected area. In this case, something must fill the large void to maintain the integrity of the spine and protect the spinal cord.

... more about:
»ACS »invasive »metastases »posterior »spine »tumors

There are typically two surgical choices in cases of extensive spinal metastases. In the more aggressive and invasive option, the surgeon opens the chest cavity from the front of the patient, which provides enough room to insert metal cages or bone grafts to replace the missing fragment. The other approach is less invasive, requiring just a small cut in the back or posterior, but only offers enough space for the surgeon to insert short expandable titanium rods, which are costly.

To develop a less expensive graft compatible with the posterior spinal surgery option, Lu, who is at the Mayo Clinic, and her postdoctoral fellow, Xifeng Liu, Ph.D., sought a material that could be dehydrated down to a size compatible with posterior spinal surgery, and then, once implanted, absorb fluids from the body, expanding to replace the missing vertebrae.

The researchers started by crosslinking oligo[poly(ethylene glycol) fumarate] to create a hollow hydrophilic cage -- the scaffold of the graft -- which could then be filled with stabilizing materials, as well as therapeutics. "When we designed this expandable tube, we wanted to be able to control the size of the graft so it would fit into the exact space left behind after removing the tumor," Lu says. The researchers also needed to control the kinetics of the expansion, because if the cage expands too quickly, a surgeon may not have enough time to position it correctly, while a slow expansion could mean a longer-than-necessary surgery.

Modifying the degree and timing of the polymer graft's expansion was a matter of chemistry, Liu says. "By modulating the molecular weight and charge of the polymer, we are able to tune the material's properties," he says. The researchers studied the effects of these chemical changes by observing the polymer grafts' expansion rates under conditions that mimic the spinal column environment in the lab. This information is key for determining the optimal size of a spinal implant for use in restorative surgery. The team identified a combination of materials that are biocompatible in animals and that they believe will work in humans.

Lu says her lab's next step is to study the grafts in cadavers and simulate an in-patient procedure. Their goal is to initiate clinical trials within the next few years.

###

A press conference on this topic will be held Tuesday, March 15, at 10 a.m. Pacific time in the San Diego Convention Center. Reporters may check-in at Room 16B (Mezzanine) in person, or watch live on YouTube http://bit.ly/ACSliveSanDiego. To ask questions online, sign in with a Google account.

Lu acknowledges funding from the National Institutes of Health.

The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 158,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.

Note to journalists: Please report that this research is being presented at a meeting of the American Chemical Society.

Follow us: Twitter | Facebook

Title

Oligo Poly (Ethylene Glycol) Fumarate Expandable Cages for Vertebral Body Replacement

Abstract

Expandable, biocompatible and biodegradable polymer grafts based on hydrophilic polymer systems were developed for vertebral body replacement in bone tissue engineering. The oligo poly(ethylene glycol) fumarate (OPF) is crosslinked into a hollow cage that, when placed in vivo, will expand in size to a predetermined diameter and length. This high degree of expansion will enable a less invasive posterior approach to vertebral body replacements. Once expanded in vivo, the implant will be filled with crosslinkable poly(propylene fumarate) (PPF) for structural support, bone regeneration and sustained release of chemotherapeutic or antibiotic agents. The kinetics of OPF expansion was explored by altering the molecular weight, charge and scaffold mold diameter. The effects of these changes were quantified by observing the expansion rates of scaffold length, diameter and mass under physiologic conditions. This information will be used to determine the optimal size of implant to be used to achieve complete restoration of the defect in a surgical setting.

Media Contact

619-525-6215 (San Diego Press Center, March 13-16)

Michael Bernstein
202-872-6042 (D.C. Office)
301-275-3221 (Cell)
m_bernstein@acs.org

Katie Cottingham, Ph.D.
301-775-8455 (Cell)
k_cottingham@acs.org

@ACSpressroom
http://www.acs.org

Michael Bernstein | EurekAlert!

Further reports about: ACS invasive metastases posterior spine tumors

More articles from Materials Sciences:

nachricht Reliable molecular toggle switch developed
30.03.2017 | Karlsruher Institut für Technologie (KIT)

nachricht Researchers shoot for success with simulations of laser pulse-material interactions
29.03.2017 | DOE/Oak Ridge National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

'On-off switch' brings researchers a step closer to potential HIV vaccine

30.03.2017 | Health and Medicine

Penn studies find promise for innovations in liquid biopsies

30.03.2017 | Health and Medicine

An LED-based device for imaging radiation induced skin damage

30.03.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>