Medicine impulses despite paraplegia

Spinal cord sends impulses to the legs despite paraplegia

01/14/2015

In paraplegia, the spinal cord sends impulses to the leg muscles despite the broken connection to the command center. The workings are similar to the headless chicken walking in the yard. Researchers at the Center for Medical Physics and Biomedical Engineering of MedUni Vienna recently discovered activation patterns in the spinal cord responsible for walking. Their results were published in the renowned journal „Brain“.

Nerve ligaments spinal cord activate muscles in the legs
In people who suffer from paraplegia, despite the lack of connection between the spinal cord and the brain by electrical impulses of a stimulator, the leg muscles can be activated and rhythmic movements are triggered. Nerve volumes, so-called locomotion centers, are responsible for this. „Using statistical techniques, we have been able to identify a small number of basic patterns underlying movement-related muscle activity in the legs that control periodic activation or inactivation of the muscles, resulting in cyclic movements such as walking“, explains study author Simon Danner. „Similar to a modular system, the neural network in the spinal cord combines these basic patterns flexibly depending on the movement requirement.“

The brainstem forms the „command Center“, however, the complex motor excitation patterns are generated by neural networks in the spinal cord. Most vertebrates have such locomotion centers. One can observe the principle that the spinal cord emits impulses even when the brain is no longer involved, for example in the headless chicken that runs around in the yard. „The spinal cord also sends out motor signals after loss of brain control, which is translated into walking and winging“, the MedUni reports in a communication on the study.

Paraplegics could benefit from insights into activation patterns for walking in the spinal cord
The findings of the researchers should be incorporated, among other things in the rehabilitation medicine. Because it could benefit patients who are paralyzed after an accident paralysis by the nerve associations that are not damaged, continue to be harnessed by electrical stimuli. This could partially re-activate lost rhythmic movement possibilities.

Further studies will investigate how the nerve groups need to be precisely stimulated. This depends, among other things, on the individual injury profile, informs MedUni. Researchers developed a unique, non-invasive method for stimulating the spinal cord that works across surface electrodes attached to the skin. „This method allows a simplified access to the nerve bandages in the spinal cord below a cross-sectional injury and can thus be made available to paraplegics without any special medical risks and burdens“, said Karen Minassian, senior author of the study. (Ag)