Summary: Spinal cord stimulation significantly decreased pain and reduced motor symptoms associated with Parkinson’s disease, both as a singular therapy and for those who deep brain stimulation proved ineffective.
A team of researchers in the United States and Japan reports that spinal cord stimulation (SCS) measurably decreased pain and reduced motor symptoms of Parkinson’s disease, both as a singular therapy and as a “salvage therapy” after deep brain stimulation (DBS) therapies were ineffective.
Writing in the September 28, 2020 issue of Bioelectronic Medicine, first author Krishnan Chakravarthy, MD, PhD, assistant professor of anesthesiology at University of California San Diego School of Medicine, and colleagues recruited 15 patients with Parkinson’s disease, a neurodegenerative disorder that is commonly characterized by physical symptoms, such as tremors and progressive difficulty walking and talking, and non-motor symptoms, such as pain and mental or behavioral changes.
The mean age of the patients was 74, with an average disease duration of 17 years. All of the patients were experiencing pain not alleviated by previous treatments. Eight had undergone earlier DBS, a non-invasive, pain therapy in which electrical currents are used to stimulate specific parts of the brain. Seven patients had received only drug treatments previously.
Researchers implanted percutaneous (through the skin) electrodes near the patients’ spines, who then chose one of three types of electrical stimulation: continuous, on-off bursts or continuous bursts of varying intensity.
Following continuous programmed treatment post-implantation, the researchers said all patients reported significant improvement, based on the Visual Analogue Scale, a measurement of pain intensity, with a mean reduction of 59 percent across all patients and stimulation modes.
Seventy-three percent of patients showed improvement in the 10-meter walk, a test that measures walking speed to assess functional mobility and gait, with an average improvement of 12 percent.
And 64 percent of patients experienced improvements in the Timed Up and Go (TUG) test, which measures how long it takes a person to rise from a chair, walk three meters, turn around, walk back to the chair and sit down. TUG assesses physical balance and stability, both standing and in motion. Average TUG improvement was 21 percent.
The authors said the findings suggest SCS may have therapeutic benefit for patients with Parkinson’s in terms of treatment for pain and motor symptoms, though they noted further studies are needed to determine whether improved motor function is due to neurological changes caused by SCS or simply decreased pain.
“We are seeing growing data on novel uses of spinal cord stimulation and specific waveforms on applications outside of chronic pain management, specifically Parkinson’s disease,” said Chakravarthy, pain management specialist at UC San Diego Health. “The potential ease of access and implantation of stimulators in the spinal cord compared to the brain suggests that this is a very exciting area for future exploration.”
Co-authors include: Rahul Chaturvedi and Rajiv Reddy, UC San Diego; Takashi Agari, Tokyo Metropolitan Neurological Hospital; Hirokazu Iwamuro, Juntendo University, Tokyo; and Ayano Matsui, National Center Hospital of Neurology and Psychiatry, Tokyo.
Single arm prospective multicenter case series on the use of burst stimulation to improve pain and motor symptoms in Parkinson’s disease
Background In this study we analyze new clinical data in the use of spinal cord stimulation (SCS) for the treatment of pain and motor symptoms in patients with Parkinson’s Disease (PD), as both a singular bioelectric therapy and as a salvage therapy after deep brain stimulation (DBS).
Methods Fifteen patients were recruited and had percutaneous electrodes implanted at the level of the thoracic or cervical spine. Participants were set to one of three stimulation modes: continuous tonic stimulation, continuous Burst stimulation (40 Hz, 500 Hz, 1000 μs), or cycle mode (on time of 10–15 s, off time of 15–30 s) with Burst (40 Hz, 500 Hz, 1000 μs). Patients completed the Visual Analogue Scale (VAS), Unified Parkinson’s Disease Rating Scale, Self-Rating Depression Scale, Hamilton Depression Rating Scale, Profile of Mood State, 10-meter walking test, and the Timed Up and Go (TUG).
Results All patients experienced significant improvement in VAS scores with a mean reduction of 59% across all patients. Patients who chose the cycling burst stimulation parameter had an average 67% reduction in VAS scores, as compared to the continuous burst parameter group, which had an average 48% reduction in VAS scores. Seventy-three percent of patients experienced improvement in the 10-meter walk, with an average improvement of 12%. Sixty-four percent of patients experienced clinically relevant improvements in the TUG, with an average improvement of 21%.
Conclusions This study points to the potential utility of SCS to address both pain and certain aspects of motor symptoms in PD patients who have and have not received DBS therapy.