Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The "disinhibited" brain: New findings on CRPS - RUB physicians report in "Neurology"

21.09.2011
The Complex Regional Pain Syndrome (CRPS), also known as Morbus Sudeck, is characterised by "disinhibition" of various sensory and motor areas in the brain.

A multidisciplinary Bochum-based research group, led by Prof. Dr. Martin Tegenthoff (Bergmannsheil Neurology Department) and Prof. Dr. Christoph Maier (Bergmannsheil Department of Pain Therapy), has now demonstrated for the first time that with unilateral CRPS excitability increases not only in the brain area processing the sense of touch of the affected hand. In addition, the brain region representing the healthy hand is simultaneously "disinhibited". The researchers report the new findings in the renowned journal "Neurology".


The figure shows fMRI signals of a CRPS patient´s somatosensory cortex after stimulation of the affected and unaffected hand compared to a healthy subject. While fMRI activation is smaller in the affected side, the diagram shows disinhibition of paired-pulse SEPs in both hemispheres of CRPS patients - although only one hand is affected

The "disinhibited" brain

New findings on CRPS – a disease characterized by severe pain
Changes to the nervous system: RUB physicians report in "Neurology"
The Complex Regional Pain Syndrome (CRPS), also known as Morbus Sudeck, is characterised by "disinhibition" of various sensory and motor areas in the brain. A multidisciplinary Bochum-based research group, led by Prof. Dr. Martin Tegenthoff (Bergmannsheil Neurology Department) and Prof. Dr. Christoph Maier (Bergmannsheil Department of Pain Therapy), has now demonstrated for the first time that with unilateral CRPS excitability increases not only in the brain area processing the sense of touch of the affected hand. In addition, the brain region representing the healthy hand is simultaneously "disinhibited". The group has been performing research on and treatment of CRPS for a number of years. The researchers report the new findings in the renowned journal "Neurology". The study was supported by the Research Funds of the Deutsche Gesetzliche Unfallversicherung (DGUV).

Is there a predisposition for CRPS?

CRPS can develop after even slight injuries and often leads to long-lasting severe pain, impairment of sensation and movement, as well as changes to the skin and the bones of the affected extremity - in many cases it even causes permanent disability. The precise cause of the syndrome is not known. Alongside inflammatory phenomena, changes in the brain also contribute to the disease becoming chronic. "Although the symptoms are mainly limited to one side of the body, some changes in the brain appear to affect both sides - a finding which could hint at an individual predisposition for the development of CRPS“, says Prof. Martin Tegenthoff.

Faulty programming in the brain

As yet, the origins of the disease remain largely unclear. Pain researchers assume that not only inflammatory factors, but also changes in the central nervous system may be a possible cause. For example, in a number of studies researchers found the representation of the affected hand on the brain’s "body map" to have shrunk, a phenomenon closely associated with the patients' pain intensity and tactile discrimination abilities.

Excitability changes on both sides

In a previous study, the Bochum group already made an astonishing discovery in the motor system of CRPS patients: the excitability of their motor hand area in the brain is increased - not only in the half of the brain controlling the affected side, but also in the half correlating to the healthy side. Following these findings hinting at a systemic disorder of the central nervous system, in the current study the group examined whether bilateral disinhibition can also be found in the brain area processing the sense of touch (somatosensory cortex). CRPS patients with unilateral symptoms of the hand were examined. After an electrical stimulation, the researchers measured the brain waves in the somatosensory brain area of the affected and the unaffected hand. Results show: the reduction of inhibition which is found on both sides in CRPS is not limited to motor areas. Those areas of the brain that process sensory perception of the hands exhibit distinct changes too.

"Disinhibition": typical of neuropathic pain

The scientists validated these findings by comparing CRPS patients with healthy volunteers and with patients suffering from pain that – in contrast to CRPS – was not caused by a disease of the nerves (so-called non-neuropathic pain). Here too, the researchers found an amazing result: the control patients showed no altered inhibition whatsoever in the hand area, they did not differ from the healthy volunteers. "This shows that the disinhibition of the brain in CRPS patients appears to be specific for neuropathic pain“, says Prof. Tegenthoff.

Systemic changes raise questions

The results indicate that the changes in the central nervous system caused by CRPS are much more complex than scientists have assumed up to now. Bilateral changes in the central sensorimotor systems that manifest in unilateral symptoms raise questions - for example: are they a cause or a consequence of the disease? The RUB scientists are presently undertaking a first approach at answering this question: in a long-term study they will accompany the patients to perform two further measurements in intervals of six months between dates. In this way, they can relate potential changes in the brain to the healing process. If a successful therapy reverses these changes, they are most probably a consequence of the disease.

Factoring in the brain

"Our research results make clear that changes in the brain play a prominent role in CRPS", says Prof. Dr. Christoph Maier. "As we already do in current pilot studies performed in the Department of Pain Therapy at Bergmannsheil, future therapies should take this aspect into account, in order to improve the treatment of what continues to be a problematic illness."

Title

Lenz M, Höffken O, Stude P, Lissek S, Schwenkreis P, Reinersmann A, Frettlöh J, Richter H, Tegenthoff M, Maier C.: Bilateral somatosensory cortex disinhibition in complex regional pain syndrome type I. Neurology. 2011 Sep 13;77(11):1096-101. Epub 2011 Aug 31.

Further information

Prof. Dr. Martin Tegenthoff, Neurological Department and Out-Patients',BG-Universitätsklinikum Bergmannsheil, Tel. +49 234 302 6810, martin.tegenthoff@rub.de

Prof. Dr. Christoph Maier, Department of Pain Therapy, BG-Universitätsklinikum Bergmannsheil, Tel. +49 234 302 6366, christoph.maier@rub.de

Editorial: Jens Wylkop

Dr. Josef König | idw
Further information:
http://www.ruhr-uni-bochum.de/

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

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

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>