Spinal cord stimulators (SCSs) have revolutionized the way we manage chronic pain. By delivering mild electrical impulses to the spinal cord, these devices can effectively interrupt pain signals, providing relief and improving quality of life for many individuals.
At Pain Specialists of America, we're committed to helping our patients achieve the best possible outcomes with their SCS therapy. Spinal cord stimulators have minimal impact on your daily activities, with almost no permanent restrictions, but it’s important to know how to address any concerns, such as overstimulation.
In this blog post, Dr. Ryan Michaud sheds light on spinal cord stimulator overstimulation. Dr. Michaud is a leading pain management specialist at PSA with extensive expertise in SCS therapy. He practices at our pain management clinic in Seguin. Dr. Michaud has been practicing interventional pain management for over 14 years and has witnessed firsthand the transformative power of SCS in helping patients overcome chronic pain.
"In simple terms," explains Dr. Michaud, "SCS overstimulation is any unpleasant sensation that a patient might experience from their spinal cord stimulator." This can range from tingling or buzzing sensations to feeling stimulation in unintended areas, and in rare cases, even a mild shock-like sensation
Overstimulation can occur for various reasons. In some cases, it may be due to the initial programming of the device, where the electrical current is set too high. However, overstimulation can also develop over time, even after the SCS has been successfully implanted.
"One of the main reasons we used to see overstimulation was due to the older types of SCS systems," says Dr. Michaud. "These systems were more voltage-driven and often caused a tingling or vibrating sensation because of where the leads were placed in the epidural space."
Fortunately, newer SCS systems have addressed this issue. "With the newer sub-threshold systems," Dr. Michaud explains, "patients typically don't experience any tingling or vibration. These systems are more sophisticated and can be adjusted to provide optimal pain relief without causing uncomfortable sensations."
Over time, it's not uncommon for scar tissue to develop around the leads of a spinal cord stimulator. Think of it like the body's natural way of healing and encapsulating a foreign object. This scar tissue, while part of the normal healing process, can sometimes lead to complications. It might compress the leads, changing their position or contact with the nerves.
It can also alter the electrical field generated by the stimulator, making the stimulation less effective or causing it to spread to unintended areas. These changes can lead to uncomfortable sensations or even overstimulation, where the tingling or buzzing feels too intense or occurs in places it shouldn't.
Just as every person is unique, so is the anatomy of their spine. Variations in the epidural space, such as a naturally narrower space or the presence of bone spurs, can affect how the electrical current from a spinal cord stimulator is distributed.
Think of it like electricity flowing through a wire; if the wire is narrower in some places, the current might be more concentrated there. Similarly, in a narrower epidural space or one with bone spurs, the electrical current from the SCS might be more focused, potentially leading to overstimulation in those areas, especially with certain movements or positions that further compress the space.
This is why personalized programming and adjustments are so important to ensure the stimulation is delivered effectively and comfortably for each individual.
A lead is a thin, insulated wire with electrodes at the tip. It's surgically placed in the epidural space (more on that below) near your spinal cord. The lead connects to the pulse generator, which is a small device implanted under your skin, usually in your abdomen or buttock. The pulse generator sends electrical signals through the lead to your spinal cord, which helps to block pain signals.
Think of the lead as an extension cord carrying electricity from the power outlet (the generator) to the appliance (your spinal cord).
The epidural space is the area between the outer covering of your spinal cord (dura mater) and the bones of your spine (vertebrae). It's filled with fat, blood vessels, and nerve roots. This is where an epidural injection is administered, and it's also where the leads for a spinal cord stimulator are placed.
Imagine the epidural space as a protective cushion surrounding your spinal cord.
Placing the leads in the epidural space allows the electrical signals from the SCS to reach the spinal cord effectively, modulating pain signals without directly affecting the spinal cord itself.
Imagine your spinal cord as a highway with pain signals traveling along it. The epidural space is like the roadside next to the highway. The SCS lead is like a device placed on the roadside that emits signals to disrupt traffic (pain signals) on the highway, making the pain less intense or even disappear.
One of the most exciting aspects of spinal cord stimulation is the continuous evolution of technology aimed at improving patient outcomes and minimizing side effects like spinal cord stimulator overstimulation. Modern SCS systems have incorporated several key advancements to enhance the therapy experience.
Closed-loop systems represent a significant leap forward. These intelligent systems constantly monitor the electrical impedance of the tissues surrounding the spinal cord. By sensing changes in impedance, which can occur with movement or changes in body position, the system can automatically adjust the stimulation parameters to maintain optimal therapy. This "feedback loop" helps to prevent overstimulation by ensuring that the electrical current is delivered consistently and effectively, even as your body moves and changes throughout the day.
Another important innovation is sub-threshold stimulation. This technique delivers electrical impulses at a level below your perception threshold, meaning you won't feel any tingling or sensation from the device. While some patients find the tingling sensation helpful, others may find it uncomfortable or distracting. Sub-threshold stimulation offers a paresthesia-free alternative, allowing you to experience pain relief without any noticeable sensation.
Finally, burst and frequency modulation are examples of newer waveforms used in SCS therapy. These waveforms deliver electrical impulses in a more targeted and controlled manner, mimicking the natural patterns of nerve activity. This can result in more effective pain relief while minimizing the risk of overstimulation. These advanced waveforms also allow for greater personalization of therapy, as the stimulation patterns can be tailored to your specific needs and preferences
If you suspect you're experiencing spinal cord stimulator overstimulation, it's crucial to contact your doctor or the PSA care team promptly. "Reprogramming the device is often the first step in addressing overstimulation," says Dr. Michaud. This involves adjusting the device settings to optimize the electrical field and reduce or eliminate uncomfortable sensations.
Your physician and the device representative will work together to manage the SCS device and address any issues like overstimulation. The device rep has specialized knowledge of the device's technology and programming, while your PSA physician understands your overall condition and pain management needs.
Oftentimes, reprogramming can be done remotely using wireless technology. This allows for more convenient adjustments and may reduce the need for in-person appointments.
In some cases, physical therapy may be recommended to help manage any muscle tightness or imbalances that may be contributing to overstimulation. If conservative measures are not effective, surgical intervention may be necessary to reposition the leads or address other underlying issues.
Dr. Michaud emphasizes the importance of open communication between patients and their healthcare providers. "If you're experiencing any unusual sensations or changes in your pain, it's crucial to let your doctor know," he advises. "We're here to help you troubleshoot any issues and ensure your SCS is working effectively."
At PSA, we're committed to providing comprehensive and compassionate care for all our patients. We believe in empowering our patients with knowledge and support, so they can actively participate in their pain management journey.
While the primary goal of spinal cord stimulation is to reduce pain, many patients experience additional benefits that extend beyond pain relief. Some of these positive effects include:
Improved sleep quality: By reducing pain and promoting relaxation, SCS can help improve sleep patterns, leading to more restful nights and increased energy levels during the day.
Spinal cord stimulation is a valuable tool for managing chronic pain, and overstimulation, while potentially bothersome, is very manageable. With the right adjustments and support, you can treat spinal cord stimulator overstimulation and continue to experience the benefits of SCS therapy to enjoy a more fulfilling life.
It's important to remember that overstimulation is not a common occurrence, especially with newer SCS systems. As Dr. Michaud reassures us, "It can happen, but... that's why your physician and care team is there to help you."
If you have any questions or concerns about your spinal cord stimulator, don't hesitate to contact your PSA care team. We're here to help you every step of the way.