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All you need to know about STIMO


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STIMO is currently receiving a great deal of publicity. Three patients with chronic paraplegia have significantly improved their walking capacities after participating in a clinical study in Switzerland that could result in a new rehabilitation program.

What exactly is STIMO?
STIMO (Stimulation Movement Overground) is an innovative clinical study for spinal cord injured patients. It combines two different treatments:
•    Precise epidural electrical stimulation of the spinal cord
•    Robot-assisted locomotion (walking) training

What is epidural stimulation?
Epidural stimulation is the application of electrical current to the spinal cord. The stimulation is carried out via a little electrode chip, which is implanted over the dura (the protective coating) of the spinal cord. It is controlled wirelessly via voice control.

The epidural stimulation technique is currently being evaluated by a number of research institutions.

What is the effect of epidural stimulation?
The stimulation is applied during rehabilitation training to facilitate movement and enhance the reorganization of nerve circuits. Although scientists do not fully understand the mechanism, the stimulation seems to “awaken” the dormant spinal tissue below the level of injury. The challenge for the patients is to learn to coordinate their intention to walk with the electrical stimulation. The STIMO participants did not take long to master this skill. They managed to walk with bodyweight support after only one week of calibration. Voluntary muscle control improved tremendously within five months of training.

And what is “robot-assisted locomotion training”?  
The term describes patients who utilize a robotic system that allows them to move freely within a room during their rehabilitation process. The system provides optimal bodyweight support, which can be constantly adjusted to the respective patient’s abilities, while ensuring the safety of the study participant and preventing falls. The system itself is called FLOAT.

 (Jean-Baptiste Mignardot)
© Jean-Baptiste Mignardot

What is the ultimate goal of STIMO?
The aim of the study is to allow participants to walk better and faster.

Have the expectations been met?  
The clinical study is still ongoing. Final results are expected within 1 to 2 years. However, early results are positively remarkable. Thus far, three participants have completed the study. All three experienced a significant improvement in terms of bodily functions. 
Notably, all three patients had sustained their respective injuries more than 4 years before they joined the study. Two of them even had previously partaken in an extensive rehabilitation program without showing any neurological recovery.
After completing the study, all three participants covered a distance of more than one kilometer on a treadmill without using their hands for support. Remarkably, even if the stimulator was constantly active, they displayed a capacity to stand still and eventually start walking at their own will. They were also able to adjust their leg movements, which is essential when encountering difficult situations such as holes or obstacles. All participants experienced substantial recovery.
Contrary to previous studies, this high-intensity training triggers changes that lead to improved function even when the stimulator is turned off. Such recoveries are simply unprecedented. Most notably, all this was achieved without any significant secondary complications, meaning that the procedure appears to be safe.

Wings for Life is proud to have supported this research project from the very beginning; and to have helped translating the findings from pre-clinic to a clinical study.

Who are the brains behind this study?
A team of scientists from the École Polytechnique Fédérale de Lausanne (EPFL) and the Lausanne University Hospital (CHUV) conducted this study in close collaboration. The figureheads of the study are Prof. Grégoire Courtine and Prof. Jocelyne Bloch, both well-known scientists and clinicians in the field.
The study is a perfect example of a successful collaboration between different centers, disciplines, specialists and funding agencies. Neuroscientists, engineers, doctors and physiotherapists worked together to create this promising treatment approach.

Prof. Courtine and Prof. Bloch
Prof. Courtine and Prof. Bloch 

When will this rehabilitation program be available to more patients?
The clinical study has yet to be completed. This will take 1 to 2 years. The team will then probably decide to test the procedure on different types of injuries. The next step would be to conduct a phase II trial with a larger cohort of patients. The timeframe for this cannot be determined at this stage.

Which patients are currently participating?
In order to maximize its chances of success, the trial has very strict rules. For this first step, the number of participants is limited to eight. Their progress is monitored for at least two years. Their lesion must be at least one year old, meaning that they are all chronic patients. They must have an incomplete spinal cord injury (graded ASIA C or D) located above the Thoracic 10 vertebra. Finally, they should be able to stand using either a walker or two crutches.

 (Jean-Baptiste Mignardot)
© Jean-Baptiste Mignardot

How is the study designed?
Seven weeks before the implantation of the stimulation device, participants are tested to assess their functions. This includes their scope of movement, sensitivity and other functions that impact their quality of life. After the stimulator has been implanted, it takes seven weeks to determine the optimal settings for each individual. The participants are then tested once more before starting the actual training program with the FLOAT system and active epidural stimulation. The rehabilitation program involves training four days per week over a period of five months. Two years after the initial implantation, participants undergo a final evaluation to determine the extent of the recovery.
 

Related Links

Information flyer for patients: https://www.sci-research.uzh.ch/dam/jcr:17152b75-ed5d-425c-8ee4-4ef44c821483/STIMO_Flyer_E.pdf
 
Media Contacts
EPFL press office, +41 21693 22 22, press@epfl.ch
CHUV press office, +41 79 556 60 00, medias@chuv.ch
 
The team behind
More about Prof. Courtine and his team: https://courtine-lab.epfl.ch/
More about Prof. Bloch: https://www.chuv.ch/fr/neurochirurgie/nch-home/le-service-en-bref/notre-equipe/nos-medecins/pre-jocelyne-bloch/
More about the robotic system FLOAT: https://www.thefloat.reha-stim.com
 
Nature Publications
Targeted neurotechnology restores walking in humans with spinal cord injury, Nature, Nov.
1st, 2018, https://doi.org/10.1038/s41586-018-0649-2
 
Electrical spinal cord stimulation must preserve proprioception to enable locomotion in
humans with spinal cord injury, Nature Neuroscience, Nov. 1st, 2018,
https://doi.org/10.1038/s41593-018-0262-6