Advanced Neuromodulation Therapy Provides Relief from Chronic Pain for Local Patients

By Josh Garcia
Tuesday, June 11, 2019

Specialty-trained surgeons at Penn State Health Milton S. Hershey Medical Center offer the most up-to-date neuromodulation therapy, dorsal root ganglion (DRG) stimulation, to address chronic neuropathic pain that is resistant to other treatment methods.

The FDA approved DRG stimulation therapy to treat complex regional pain syndrome (CRPS) types I and II in 2016. By 2017, Penn State Health had already incorporated this treatment, and it is currently the only academic institution in central Pennsylvania providing this option, says Michael Sather, MD, FAANS, neurosurgeon at the Milton S. Hershey Medical Center.

A Quality-of-Life Issue

Neuropathic pain can be severe and constant, and conventional medication and noninvasive treatment methods may prove ineffective in addressing some patients’ symptoms. This pain, even if localized in a single area, can negatively affect almost all aspects of life.

“Some people describe the pain as a burning or electrical sensation, and their skin becomes sensitive to touch,” Dr. Sather says. “Patients sometimes describe their foot as feeling on fire and may need to sleep with their foot outside of the sheets at night. They may be unable to wear shoes or socks.”

CRPS I is not linked to one specific nerve injury and may instead affect a region or network of neurons. Conversely, CRPS II is linked to a single, confirmed nerve injury. Although DRG stimulation was designed to treat CRPS, the therapy may also be beneficial for patients with other types of nerve pain.

“Anything we would describe as neuropathic pain, such as peripheral neuropathy in the feet, could benefit from DRG therapy,” Dr. Sather says.

“For patients with complex regional pain syndrome or neuropathic chronic pain who are not responding to other therapies, dorsal root ganglion stimulation therapy can be life-changing.”
— Michael Sather, MD, FAANS, neurosurgeon at Penn State Health Milton S. Hershey Medical Center

An Effective Alternative

DRG stimulation therapy is a form of neuromodulation, which refers to the altering of nerve activity using electrical or pharmaceutical methods. During neuromodulation, electricity or medication is delivered directly to targeted areas and nerves to treat chronic and neuropathic pain, weakness, partial paralysis, ischemic disorders, Parkinson’s disease, pelvic disorders, incontinence and other conditions.

“Neuromodulation employs advanced medical techniques to suppress abnormal signals in the brain, be it stimulation of different areas of the central nervous system or nerves that work on specific areas of the body,” says Elias B. Rizk, MD, adult and pediatric neurosurgeon at Hershey Medical Center.

Specifically, DRG stimulation therapy targets nerve bundles in the spine.

“The DRG is a collection of sensory nerve cell bodies that sits just outside of the spinal canal,” Dr. Sather explains. “These cells are involved with pain, sensation and touch. Normally, the DRG will not fire pain signals to the brain unless there’s a significant stimulus, but for people with chronic pain, the DRG can be hyperexcitable, which explains their chronic pain and hypersensitivity.”

DRG stimulation involves the placement of one to four electrodes on or near the bundle of nerves, depending on the extent and severity of a patient’s pain. This pain can be caused by CRPS or another neurological condition. A small battery pack is also implanted under the skin near the waistline. The electrodes are connected to the battery, which delivers the prescribed amount of electricity to the affected DRG.

Before the entire system is implanted, however, patients complete a short trial to determine whether DRG stimulation is the optimal treatment for them. During this approximately one-week trial, the leads are placed in the patient’s back and connected to an external battery pack. If the patient experiences at least a 50 percent reduction in pain during the trial, an outpatient surgical procedure is scheduled to implant the leads and battery under the skin.

“About 90 percent of the time, if the trial is successful, the treatment will also be successful,” Dr. Sather says. “The procedure itself usually lasts approximately two hours and requires only two incisions: one for the battery and one for the electrodes.”

The availability of DRG stimulation therapy at Hershey Medical Center enables central Pennsylvanians to benefit from this leading-edge treatment option without the burden of traveling to major metropolitan areas for appointments and consultations.

“Our clinicians are ready and available to talk directly to referring providers, review cases and provide input on patients,” Dr. Rizk says. “We’re easily accessible and eager to improve the health of our central Pennsylvania population.”

“We are unique in that we offer a number of services that are not available statewide. Not many healthcare providers are accredited or approved to perform dorsal root ganglion (DRG) stimulation therapy. Between spinal cord, deep brain and DRG stimulators, we cover the gamut of neuromodulation.”
— Elias B. Rizk, MD, adult and pediatric neurosurgeon at Penn State Health Milton S. Hershey Medical Center

The Future of Neuromodulation

In addition to offering DRG therapy, Hershey Medical Center stays on the forefront of neuromodulation by pursuing research and clinical trials, including current trials examining patients with spinal cord stimulators for pain management. Further, it has the resources necessary for success in that pursuit.

“Our faculty is entrenched in research,” Dr. Rizk says. “Penn State Health is in the top 10 neurosurgical departments nationwide in terms of funding from the National Institutes of Health for clinical research.”

Other ongoing trials are examining peripheral nerve diseases and new forms of neuromodulation, with applications extending far beyond chronic pain management.

“We’re looking at areas of modulation that may have the capacity to improve breathing or directly stimulate specific limbs for stroke patients,” Dr. Rizk says. “Our colleagues are working with electrical engineers and developing technology to help modulate neurons on a larger scale. New devices will be coming to the market in the next decade thanks to research being done at Penn State Health.”


Visit hmc.pennstatehealth.org/neurosurgery or call 717-531-3828 for more information.