Neurostimulation: Specialists & treatment information

What is neurostimulation?

Neurostimulation has been known as a pain therapy method since the end of the 1960s. Since the 1980s, the method has been used as standard in pain therapy for chronic pain.

Chronic pain in particular is suitable for treatment using neurostimulation. Chronic pain is defined as pain that lasts longer than six months or recurs repeatedly during this period. Common areas of application are

• The back,
• neck,
• arms and
• legs.

Neurostimulation is also known as spinal cord stimulation (SCS). The procedure corresponds to nerve stimulation by means of an electrical impulse.

Pain signals reach the brain via the spinal cord. Neurostimulators influence this process.

Stimulation can be conducted in both efferent and afferent directions:

• Efferent: impulses are sent from the central nervous system to the periphery.
• Afferent: impulses are sent from the periphery to the central nervous system.

Auricular neurostimulation is a minimally invasive treatment method for implanting a stimulation system. This system blocks the transmission of pain stimuli to afferent nerve branches. The sensation of pain is thus intercepted before it enters consciousness.

Specialists in neurostimulation are pain physicians, neurosurgeons and spinal surgeons.

How does neurostimulation work?

Neurostimulators inhibit the excitation of overactive nerves by means of a pulse generator. This electronic pulse generator corresponds to a neuromodulator or neurostimulator. The device stimulates individual sections of the spinal cord using weak electrical impulses.

The neuromodulator communicates with an electrode. This thin wire sits in the spinal canal of the person suffering from pain and transmits the impulses sent to it to the nerves of the spinal cord.

Through these impulses, the neurostimulation overrides the pain conduction of individual nerves before the pain signal reaches the brain. Instead of pain, the patient feels a pleasant tingling sensation in the former area of pain.

In order to determine their suitability for neurostimulation, patients receive an external stimulator before the planned implantation of a neurostimulator. After a test phase, the electrode-receiver system (SCS system) can be implanted if the patient is suitable.

Neurostimulation makes use of the nervous system and intercepts pain impulses before they reach the brain © C.Castilla | AdobeStock

What is a neurostimulator?

Different types of neurostimulators are used in pain therapy. In addition to implantable stimulators, there are also external neurostimulators.

The stimulator is about the size of a pack of cigarettes and contains

• high-performance electronics,
• batteries and
• multipolar electrodes.

The neurostimulator supplies the electrode with impulses. The electrode is responsible for transmitting impulses to the corresponding nerves.

The doctor programs implantable neurostimulators following implantation. The patient can then switch the neurostimulator on and off and change the impulses within medically predefined limits. This allows them to adapt the stimulation to their current pain symptoms.

When can neurostimulation be used?

In principle, neurostimulation is particularly suitable for indications such as

• chronic pain in the back, neck or limbs
• neuropathic pain with burning or numbness or
• minor pain relief through conventional methods such as physiotherapy or painkillers.

Neurostimulation is thought to trigger anti-inflammatory processes. It also intervenes in microcirculation via sensory pathways.

Clinical studies therefore prove the effectiveness of nerve stimulation in the context of chronic diseases such as

• Nerve root damage (radiculopathies)
• Phantom pain and residual limb pain
• circulatory disorders
• Zoster neuralgia and post-zoster neuralgia with herpes zoster
• Incomplete spinal cord symptoms
• complex regional pain syndromes (CRPS)
• angina pectoris
• (chronic) back pain caused by events such as a herniated disc

Benefits and risks of neurostimulation

Clinical studies have shown that neurostimulation relieves chronic pain by up to 50 percent. This pain relief enables painless movement and thus promotes activity. As a result, neurostimulation improves the quality of life in chronic diseases.

The pain-relieving effect means that patients have little or no recourse to painkillers. In this way, neuromodulation using a neurostimulator also reduces the side effects associated with taking medication.

Advantages of neurostimulation

Compared to other procedures, neuromodulation treatment with a stimulator has many advantages. Neurostimulation

• relieves pain,
• reduces the need for painkillers,
• improves the quality of life,
• can be tried out in a test phase,
• can be reversed,
• does not permanently alter nerve conduction or the spinal cord,
• can be customized.

Risks and side effects of neurostimulation

Like any treatment procedure, neurostimulation is associated with some risks and side effects.

• The electrode can slip.
• Pain relief can fail to materialize due to incorrectly placed electrodes.
• Unpleasant sensations may occur in the stimulation area.

As the treatment procedure requires surgery, there are also the usual surgical risks. In the rarest of cases

• haematomas (bruising) or seromas (accumulation of fluid) form at the implantation site,
• the spinal cord is injured during the procedure,
• infection of the wound occurs,
• several operations are required due to complications.

The attending physician weighs up the risks and benefits in each individual case and decides on the suitability of the patient.