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 Tag it EASI – a new method for accurate protein analysis
19.06.2018 | Max-Planck-Institut für Biochemie

nachricht How to track and trace a protein: Nanosensors monitor intracellular deliveries
19.06.2018 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

New material for splitting water

19.06.2018 | Physics and Astronomy

Cementless fly ash binder makes concrete 'green'

19.06.2018 | Materials Sciences

Overdosing on Calcium

19.06.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>