Components of a Spinal Cord Stimulation System

Neurostimulators and Dorsal Column Stimulators

How Neurostimulation Works

How spinal cord stimulation works to mask chronic back pain.
What Happens When You Wear a Spinal Cord Stimulator A graphic representation on how spinal cord stimulation works to mask chronic back pain. Boston Scientific

Spinal cord stimulators have several components. If you are considering neurostimulation to control chronic back pain, check out the components in this gallery of images (and click on each to get a larger image and background information). Neurostimulators are also called dorsal column stimulators.

This is a graphic representation of how spinal cord stimulation works:

(1) You have a problem in your spine that creates pain.

(2) The spinal cord stimulator device is implanted in either your abdominal or buttock area. Leads attached to it are routed to your spinal cord.

(3) Electrodes on the leads deliver electricity generated by the device to the spinal cord. This electricity interrupts the pain signal that is coming from the problem area.

(4) The signals travel to the brain where they are interpreted. Because the pain signals are interrupted by the stimulator, you now feel pins and needles in the area of your back problem.

Neurostimulation Systems

A neurostimulation-or spinal cord stimulation system-consists of a spinal cord stimulator, leads.
Components of a Spinal Cord Stimulation System A neurostimulation - or spinal cord stimulation system - consists of a spinal cord stimulator, leads, a charger and a remote control device. Boston Scientific

With neurostimulation, a device and leads are implanted surgically. But there are also a couple of other components to a spinal cord stimulation system.

A spinal cord stimulation system consists of 4 main components that work together to deliver neurostimulation to the area your doctor determines as the source of the pain (called the pain generator).

The small silver device on the right is the generator (or power source). It weighs about 1.164 ounces. As you can see, the generator comes with leads, a remote control, and a recharger. The particular system shown here is a rechargable IPG system.

The Spinal Cord Stimulator Device

IPG-Rechargeable Implantable Pulse Generator
The Neurostimulation Device is the Basic Component of the System The IPG is a commonly used type of spinal cord stimulator device. Boston Scientific

The spinal cord stimulation device is the basic component in the system.

Any neurostimulation system has a spinal cord stimulator. The spinal cord stimulation device is the basic component; it is implanted in either the abdominal or buttock area by your doctor. Leads are then run from it to the epidural space in the spinal canal.

A rechargeable implantable pulse generator (IPG) type of stimulator is shown here. The rechargeable IPG is an example of the latest technology in spinal cord stimulation devices (and systems). Patients and doctors like the new IPG technology because the devices are usually small, which gives some flexibility as to where they can be implanted. Other types of devices, which use older technologies, are also still on the market.

The Spinal Cord Stimulator Device - Continued

St Jude EON Mini Neurostimulator
The Latest Technology in Neurostimulation Devices St. Jude EON Mini Neurostimulator.

This is a neurostimulator that is comparable to the device shown on the previous page.

Like the the previous spinal cord stimulator, this unit is an implantable pulse generator (IPG), and it represents the latest in technology as of 2009.

Both units are small, with rechargeable batteries. Having the rechargeable battery feature means you don't need to rush to the doctor whenever your battery wears out.

There are differences in neurostimulator models. For example, this particular device allows the doctor to be able to adjust settings for up to eight painful areas at one time. Other models allow for each lead to be programmed separately. To learn more, talk with your doctor about the types of features (and limitations) of the device she is planning on using.

Leads and Electrodes on Neurostimulators

Leads are wires that go from the neurostimulator to the spinal cords.
Routing the New Signals that will Mask Your Pain Spinal cord stimulators need leads to deliver the signals that will interrupt the feeling of pain. Leads are wires that go from the neurostimulator device (implanted in the back or abdominal area) to the spinal cord. Boston Scientific

The neurostimulator device generates electrical signals that mask the pain. But without leads that attach to it and the spinal cord area, you won't get relief.

Pictured here are two different leads, or wire-like structures that are connected to the generator. At the opposite end of the lead are electrodes; this is the end that is placed in the epidural space, near the spinal cord. The electrodes deliver the electrical signals to the spinal cord.

There are two main types of leads: percutaneous and surgical. Percutaneous means "under the skin," so a percutaneous lead will be inserted in the soft tissue by means of an incision. Placement of the other type of lead is often left to spine surgeons who have more skill and practice in traditional back surgery.

Some manufacturers make different types of percutaneous leads, claiming that this will improve the pain management provided by the system. For example, on the model on the right shown here, according to the manufacturer, the leads can programmed individually by the doctor. But the degree to which this feature is helpful in relieving back pain is debatable, according to some physicians.

Remote Control Device for a Spinal Cord Stimulation System

A remote control for the spinal cord stimulator may help you control how much pain relief you get.
Control Your Pain Management with the SCS Remote Control A remote control for the spinal cord stimulator may help you control how much pain relief you get. Boston Scientific

One of the nice things about many models of spinal cord simulators is that you can control, to a certain extent, the amount of stimulation you get. This is a picture of a remote for an implantable pulse generator type neurostimulation system.

Battery Charger for Spinal Cord Stimulators

Rechargable IPG spinal cord stimulators need to be recharged from time to time.
Rechargable IPG Spinal Cord Stimulators Need to be Recharged Rechargeable implantable pulse generator (IPG) spinal cord stimulators need to be recharged regularly. Shown here is a charger for an IPG neurostimulation system. Boston Scientific

This is an example of a charger for an implantable pulse generator (IPG) system. If your spinal cord stimulator is rechargeable, you will periodically have to spend time recharging the battery, which is located inside the implanted device.

The amount of time it takes to charge the generator varies according to the brand and model, and age and condition of the device. (Generally, it's about 10 years). The same is true for the amount of time the battery can hold a charge, i.e., how long you can go between charges. The older the battery, the more time charging takes, and the more often you will need to recharge.

To charge a neurostimulator battery, you hold the charger over the area where the device is implanted for a specified period of time.

If your stimulator is not a rechargeable IPG, you will need to have a simple surgery to get the battery changed.

Features of an IPG Neurostimulator

The nice thing about a late model IPG neurostimulator is its small size.
The Small Size of an IPG Neurostimulator May Mean More Comfort for You The nice thing about the newest model of IPG neurostimulator is its small size. St. Jude Medical

The latest models of IPGs are the smallest neurostimulator devices out there. This feature may translate into more comfort for you day-to-day.

As mentioned in the section on devices, the latest IPGs (implanted pulse generator neurostimulator) represents the latest technology has to offer when it comes to spinal cord stimulation systems.

What does this mean to you?

Along with the ability to recharge your battery at home (and avoid going for surgery every time you need a new one), the latest models of IPG devices are very small in size. A tiny neurostimulator means that the incision required to implant it will be minimal. The small size also opens up choices as to where it can be implanted, and this allows the surgeon to take your day-to-day device-related comfort level into consideration. It may even be possible to implant the device up to 2.5 cm into the body, which could decrease how noticeable it is. (Implantation deeper than 2.5 cm won't allow you to recharge the battery, however.)

Size Specs of Neurostimulators

Size of an IPG Neurostimulation Device as Compared to a Silver Dollar
How Small is Small? Size Specs of the latest generation IPG Neurostimulators-How Small is Small?. St. Jude Medical

As the device market advances, each new generation of neurostimulator will most likely be smaller in size than the previous. Shown here is one of the latest IPG neurostimulation devices (2009), as it compares to a U.S. silver dollar. As you can see, it is just a bit larger than the coin. This model weighs about 1 ounce and is 10 millimeters in thickness. Models produced by different manufacturers vary slightly in their dimensions.

Older IPG Neurostimulators

Older models of neurostimulators are comparable to the new spinal cord stimulators in some ways.
How Do Older IPG Neurostimulators Compare with the Latest? Older models of neurostimulators are comparable to the new spinal cord stimulators in some ways, but not in others. St. Jude Medical

Older models of neurostimulators are comparable to the new spinal cord stimulators in some ways, but not in others.

This is an older model neurostimulator. As you can see, it is not as small as the latest devices on the market, but it is an IPG.

According to the manufacturer, this device is about the size of a large pocket watch or a small stopwatch. It weighs about 2.65 oz (as compared to about 1 oz for the newest models).

Like the latest devices, the battery is rechargeable and will last 10 years.

If you need pain control power and are willing and able to regularly recharge the device yourself, this slightly older model may be the neurostimulator for you. Consult with your physician about your options.

Older Non-Rechargeable IPG Neurostimulators

There are less bells and whistles in older, non-IPG model neurostimulators.
Features of Older Model Neurostimulators and Spinal Cord Stimulators There are less bells and whistles in older, non-rechargeable IPG model neurostimulators and spinal cord stimulators. St. Jude Medical

Here is an early version of the implantable pulse generator neurostimulators. This one is a non-rechargable IPG, which means you would need to undergo a procedure every time the battery gives out in order to continue to get pain relief. Though you have to have the battery changed during a surgery, you gain the bonus of daily convenience; you will not need to remember to recharge your device every 24 hours, for example.

You can expect that the battery inside a device such as this one will last approximately 7 years.

The older the model, the larger it tends to be. The model shown here is about the size of a large stopwatch and weighs approximately 2.93 oz.

Non-IPG Neurostimulator

The non-rechargable non-IPG might be an option if you can't deal with regular recharges.
Older Non-IPG Spinal Cord Stimulator Features - or Lack Of... This is one of the oldest neurostimulators still on the market. St. Jude Medical

This is one of the oldest types of neurostimulators, the primary cell (non-rechargeable). The only model older than this one is the radio frequency system. For the unit shown here, you can expect the battery to last for 5 to 7 years. You will need battery replacement surgery when the battery dies.

This neurostimulator is also an option for chronic pain patients who prefer or require the simplicity of a non-rechargeable medical device.

Radiofrequency Neurostimulators

The radio frequency or RF model is the oldest neurostimulation technology in use today.
Radio Frequency - The Oldest Type Spinal Cord Stimulator The radio frequency or RF model is the oldest neurostimulation technology in use today. St. Jude Medical

The radio frequency stimulator has the dubious distinction of being the oldest type of neurostimulation technology still in use today.

The radio frequency systems were among the first spinal cord stimulators used to treat chronic back pain. They are all but outdated today. One reason is that they use an older technology. The IPG neurostimulators (the newer type) are small, unobtrusive and offer a number of features older models such as the RF system cannot.

With the radio frequency neurostimulator system, the receiver and the leads are surgically implanted under the skin. The RF is the only type of spinal cord stimulator in which the transmitter is "worn" outside the body (on a belt pack). Through an incision, a wire is run from the battery (located outside your body) to the receiver (located inside your body). Then the leads are run from the receiver to the place in your spine your doctor had determined as the source of your pain.

With this type of neurostimulator, you will still have to go through a procedure, but not to change the battery. This can have advantages, although wearing the battery will be more cumbersome for you day-to-day. If you can't remember or don't want to be bothered with recharging your neurostimulator, the RF system might be a viable choice for you. Consult with your pain management specialist about your options.

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