Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New cements for vertebral lesions

08.02.2008
A number of researchers at the Department of Polymer Science and Technology at the Chemistry Faculty from San Sebastian at the University of the Basque Country, led by Ms Isabel Goñi and Ms Marilo Gurrutxaga, are studying new formulae for acrylic copolymers and compounds in order to obtain efficacious, multiuse bone cements with reduced side effects.

Acrylic bone cements based on polymethylmetacrylate (PMMA) have been traditionally used in hip replacements in order to set the prothesis inside the bone. On the other hand, with new techniques such as vertebroplastia, the cement is injected into an affected vertebra by means of long and narrow needles, visualized with X rays.

Vertebroplastia is mainly applied in the treatment of vertebral fractures due to osteoporosis or bone tumours, with the aim of reinforcing the bone and alleviating the pain. It is a minimally invasive and rapid technique (~ 40 min/vertebra) and efficacious in alleviating pain (80-90% in 72 h) due to the mechanical reinforcement provided by the cement. Nevertheless, the risk of migration of the cement and of bone necrosis has to be taken into account given the exothermia of the polymerisation reaction and the toxicity of the monomer. Researchers at the Department of Polymer Science and Technology at the University of the Basque Country (UPV/EHU) focused on this, amongst other items, in this study.

Viscosity and radiopacity

... more about:
»Agent »PMMA »acrylic »effect »rays

The formulae used for the cement in vertebroplasty consist basically of the monomer, PMMA pearls and a radiopaque agent. This last ingredient is what enables the visualisation of the cement mass during the injection. These formulae have to comply principally with the following requisites: appropriate viscosity and high radiopacity. The cement has to have a certain consistency so as not to drip, and sufficient fluidity to be injected, as well as being highly visual with X rays, so that the surgeon can see what is being injected.

In order to adapt the traditional formulae to new applications, surgeons usually modify the cements when operating, in order to facilitate their injection, either adding more monomer in liquid phase to reduce viscosity and increase the time for working or, otherwise, increasing their visibility for the X rays by the addition of more radiopaque agents. All these changes affect the properties of the cement and its toxicity. This is why researchers at the Department of Polymer Science and Technology at the UPV/EHU are seeking to develop new formulae for acrylic bone cements designed specifically for injectable use and which provide what could possibly be an additional therapeutic action.

The UPV/EHU researchers have seen that it is possible to obtain injectable bone cements with rheological properties and with suitable selection of PMMA pearl particle size. Given that the greater the size of the pearls, in some way the heat produced during polymerisation is dissipated more and not so much exothermia is produced in the polymerisation reaction, thus producing a greater heating of the tissue.

Once the PMMA pearl particle size is selected, certain radiopaque and/or therapeutic agents are incorporated that can intervene in the process of curing and quantify the effects produced in the properties of the cement. On the one hand, bismuth salicylate has been added, combining the analgesic effects of salycilic acid with that of the bismuth, a metal easily visible using X rays. Thus, the results reflect a suitable radiopacity provided by the bismuth, a therapeutic effect of the salycilate and less toxicity and good compatibility overall.

Also, acrylic cements are formulated by adding bioactive elements, the idea being to obtain the interaction between the cement and the biological tissue, in some way causing the fixing of the tissue (osteoregeneration). In fact, strontium hydroxiapatite has been incorporated in order to combine the visibility of strontium and the immediate fixing of acrylic cement with the long-term fixing of the bioactive ingredient.

Finally, thanks to collaboration with other research centres, the EHU-UPV researchers carried out in vitro and in vivo biocompatibility studies. The studies undertaken to date have not given any more problems than cements with traditional commercial formulae.

Irati Kortabitarte | alfa
Further information:
http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=1619&hizk=I

Further reports about: Agent PMMA acrylic effect rays

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>