Neurostimulation

What is neurostimulation (spinal cord stimulation)?

Neurostimulation is the term given to the electrical stimulation of nerves, normally using an implanted pulse generator. This procedure is used in various therapies to treat different medical conditions, such as through bladder or bowel pacemakers for urinary or fecal incontinence.

This article focuses on spinal cord stimulation (also known as SCS), where neurostimulation is used to treat chronic pain.

How does neurostimulation work?

In spinal cord stimulation, electrodes are implanted near the spinal cord. An impulse generator, which can either be placed under the skin in the fatty tissue or worn on the body, sends out electrical impulses to stimulate the spinal cords nerve cells. These impulses affect pain pathways through mechanisms that are not yet fully understood.

We differentiate between two types of spinal cord stimulation.

Low-frequency spinal cord stimulation

This type of neurostimulation involves low-frequency current and is thought to work by over-stimulating sensitive nerve fibers that transmit sensory impulses from the periphery to the brain. As these fibers project to the same spinal cord neurons as pain fibers, the two signals behave competitively, and the pain is suppressed. The pain is however replaced by a tingling sensation in the affected area.

Additionally, the overstimulation of sensory nerves activates inhibitory interneurons, which can partially deactivate the pain-conducting nerve cells that are pathologically overactive in chronic pain, thereby reducing the sensation of pain.

High-frequency spinal cord stimulation

High-frequency stimulation is more commonly used today than low-frequency stimulation. In this method, high-frequency currents are applied, which likely lead to the selective activation of inhibitory interneurons, reducing the activity of pain fibers. High-frequency stimulation does not cause tingling sensations, making it suitable for nighttime use, which can improve sleep quality.

Who is neurostimulation suitable for?

Neurostimulation is suitable for the treatment of different types of chronic pain:

• Neuropathic pain (pain that is caused or sustained by a nerve disease or the blood vessels that supply it, for example, multiple sclerosis, alcohol abuse or diabetes mellitus)
• Ischemic pain (pain caused or sustained by circulatory disorders, for example in the context of peripheral arterial occlusive disease)
• Vegetative-sympathetic pain (pain that is caused or maintained by dysfunction or overactivation of the sympathetic nervous system, such as in CRPS (chronic regional pain syndrome)).

Treatment is not indicated for nociceptive pain, in other words pain that is triggered by either actual or impending tissue damage.

However, there is a growing consensus among specialists that chronic pain in many conditions, such as cancer, rheumatic diseases, or post-surgical pain, may represent a "mixed-pain syndrome," which has both nociceptive and neuropathic components. This suggests that neurostimulation might also be useful in treating such cases in the future. For certain specific conditions involving mixed-pain syndrome, studies are already showing promising results. An example is post-nucleotomy syndrome, where persistent pain occurs after spinal disc surgery or other spinal canal procedures.

Patients who meet one or more of the following criteria are not suitable for this treatment:

• Untreated psychiatric disorders
• Substance abuse or dependency
• Severe blood clotting disorders
• Other implants that generate electrical impulses (e.g., pacemakers)
• Advanced-stage cancer
• Infections at the implantation site

How does neurostimulation treatment work?

As this procedure is only effective for specific types of pain, the treatment begins with a comprehensive medical history and examination to determine if the patient belongs to a group that could benefit from neurostimulation therapy.

Furthermore, the patients are also informed about the entire procedure, including the fact that while pain reduction is often achievable, complete pain relief may not be. This expectation management is crucial, as unmet expectations can negatively impact the course of chronic pain conditions.

The electrodes are implanted on the surface of the spinal cord in a minor surgical procedure. For low-frequency stimulation, the procedure must be performed under local anesthesia, as test electrical impulses are applied to check the position of the electrodes, and the patient needs to confirm if the area with tingling matches the painful area. In the case of high-frequency neurostimulation, implantation can be done under general anesthesia, as precise positioning is less critical in this case.

Following the surgery, a trial phase lasting several days to weeks is conducted. Neurostimulation is provided by an external pulse generator. If pain is reduced by at least half during this trial period, it is considered a positive response to the treatment. The pulse generator is then usually implanted under the skin of the lower abdomen or buttocks.

Further treatment should be conducted in connection with specialized medical supervision, with regular follow-up appointments.

What are the costs of neurostimulation?

Where there is an appropriate medical indication, the entire cost of neurostimulation is covered by statutory and private health insurance companies.

Which doctors and clinics specialize in neurostimulation? 

Spinal cord stimulation is performed under the supervision of pain specialists. Medical specialists in various fields can specialize in this by undergoing further training in the field of special pain therapy. 

The implantation of the electrodes is carried out by a neurosurgeon. 

The treatment is therefore often offered in multidisciplinary practices or clinics.

Anyone in need of a doctor would expect the best possible medical care for themselves. Therefore, patients are looking for the most suitable clinic for their needs. Since this is not an objective decision and a respectable doctor would refrain from claiming to be the best, patients must trust the experience of a doctor.

We can help you find an appropriate expert for your condition. All the doctors and clinics listed have undergone extensive review and have been verified by us for their outstanding expertise in the field of neurostimulation. They are looking forward to and are ready to address your questions and treatment requests.