Rapid technological changes in spinal cord stimulation and peripheral nerve field stimulation are extending the therapy’s potential benefits to a wider range of people.
Since the approval of spinal cord stimulation by the U.S. Food and Drug Administration in 1989, manufacturers have continued to develop features designed to make the devices used in spinal cord therapy smaller, more effective, and more comfortable.
High Frequency Spinal Cord Stimulation
One of the changes in spinal cord stimulation is the introduction of systems using high frequency pulses, rather than the low frequencies traditionally used. High-frequency therapy was approved by the U.S. Food and Drug Administration in 2015, and the medical literature has shown some advantages to high-frequency therapy.
- One research study showed that with high-frequency therapy, pain was reduced by more than half in 85% of study participants with back pain and 83% of those with leg pain when high-frequency therapy was used.
- In the same study, when low-frequency therapy was used, pain was reduced by more than half in 44% of participants with back pain and 56% of those with leg pain.1
The effectiveness of spinal cord stimulation in treating back pain is notable. While both high- and low-frequency systems effectively relieve radicular pain in the legs and feet, low-frequency therapy has generally not worked as well for back pain.2
The study also found significantly more people improved their functioning and were able to reduce or eliminate opioid use when using high-frequency therapy rather than low-frequency therapy. This reduction in opioid use by study participants may be encouraging for individuals wanting to reduce their own reliance on opioid medication. More than three-fourths of the study participants used opioid medications.1
Additional Forms of Spinal Cord Stimulation
Two other forms of spinal cord stimulation have further expanded the therapy’s potential usefulness in recent years.
Dorsal Root Ganglion Therapy
Dorsal root ganglion therapy is a targeted approach that has been especially effective in treating groin and foot pain. Rather than working through the spinal cord, the therapy is applied to the dorsal root ganglion, a grouping of specialized nerves near the spinal cord at the base of each branching spinal nerve. These areas have often been challenging to treat with other forms of spinal cord stimulation. The U.S. Food and Drug Administration has approved dorsal root ganglion stimulation for complex regional pain syndrome.
Burst Spinal Cord Stimulation
Burst spinal cord stimulation, which delivers closely spaced, high-frequency current, has been effective in relieving pain without the associated tingling sensation called paresthesia. It appears to be helpful for people who have built up a tolerance for the pain-relieving effects of traditional spinal cord therapy.3
MRI-Safe Devices Offered
In the past, people who needed to have magnetic resonance imaging (MRI) scans were not able to benefit from spinal cord stimulation. Energy from an MRI was considered hazardous to the implanted devices.
New MRI-safe spinal cord stimulation devices are now available. In some cases, the device allows whole-body MRI scans, while others are designed to accommodate only certain types of MRIs.
This is a major advantage, since many people who are candidates for spinal cord stimulation have coexisting conditions that must be monitored with MRIs.
Wireless System, Miniaturization Make Process Less Invasive
Spinal cord stimulation is becoming less invasive due to miniaturization of generators and other devices. With smaller generators, the incision needed to insert them has also gotten smaller. For example, one new device offers a generator the size of a matchstick.
A new wireless system takes miniaturization a step further. The leads, electrodes, and a micro-transmitter are all implanted in the spinal space with a hollow needle. A small wearable antenna sends signals wirelessly to the electrical contacts in the spinal cavity. This eliminates the need for more extensive surgery to insert the generator as well as the need to eventually replace it. It also avoids potential irritation or infection in the area where the generator is implanted.
Rechargeable vs. Non-rechargeable: The Pros and Cons
Rechargeable generators are often smaller and last longer before they need to be replaced. A potential drawback is that they need to be charged regularly, and the use of high-frequency spinal cord stimulation may require even more frequent charging.
Non-rechargeable generators are simpler in terms of day-to-day maintenance, but require a surgical revision to change the battery. This type of generator may be easier for patients who have difficulty with technology.
Therapy Becoming Easier to Use
Other innovations making daily life easier for people using spinal cord stimulation include:
- Automatic adjustments. Controllers with sensors that automatically adapt stimulation levels to people’s movements are available. Other models offer multiple programs of stimulation based on factors including pain and body movements.
- Long-lasting generators. As generators have gotten smaller, their batteries have also improved. Some rechargeable implantable pulse generators are now expected to last 10 to 25 years before needing to be surgically removed.
Innovations in the devices used for spinal cord stimulation may offer improved pain relief, comfort, and convenience over earlier models. In the future, there may be advancements that track movement and adapt the stimulation accordingly, or even use radiofrequency wireless technology that could avoid the need for an implanted generator.