A study published in the March issue of Neurosurgery, the official journal of the Congress of Neurological Surgeons, describes a new method of electrical stimulation that uses an implanted device with three columns of electrodes, which could increase the efficiency of spinal cord stimulation (SCS) for severe back pain.
Spinal cord stimulation gains maximum benefits with the help of the “tripolar lead” device, which is used for patients in whom back surgery has failed. The device could broaden electrical stimulation technique applications.
SCS involves applying electrodes that are implanted along the spine with a gentle, stimulating electrical current that, if successful, produces a feeling of numbness that overpowers the sensation of pain.
Previous studies have demonstrated that SCS has proven successful in patients with back and leg pain that remains unresponsive to other treatments. Whilst SCS stimulation has proven extremely effective for “radicular” pain that spreads down the leg, it only shows limited success in treating “axial” pain along the spine, particularly lower back pain.
Dr. Rigoard, and his team assessed the new SCS device in eleven patients who suffered from severe pain after unsuccessful back surgery. All patients were implanted with the recently approved stimulation device, which features three columns of electrodes instead of just one.
The aim of the new device is that 16 electrodes in a three-column configuration can offer overlapping areas of stimulation, therefore maximizing the impact of SCS. Dr. Rigoard, and his team systematically evaluated effects of 43 different electrode stimulation patterns to establish the most efficient way for relieving “axial” pain in the lower spine as well as “radicular” pain in the leg.
The researchers declared:
“The tripolar lead successfully generated paresthesia [numbness] in both bilateral back and leg territories in 9 patients (81.8%).”
The study demonstrated that stimulation patterns with two or three columns provided offered superior pain relief compared with single-column patterns.
After six months of SCS stimulation with the new device, the researchers observed substantial improvements in pain relief, with a reduced average total pain score that includes both back and leg pain, from 8.2 to 2.25 on a scale from 0 to 10.
The new tripolar lead and stimulation patterns could potentially help in surpassing restrictions of earlier approaches to SCS, especially for axial pain. According to the researchers, the device requires larger studies to confirm its efficacy, in particular, with regard to helping those who suffer from severe, disabling back pain to resume more normal activities.
Dr. Rigoard and his team conclude:
“This may lead physicians to reconsider new indications for spinal cord stimulation.”
They speculate that the new techniques could potentially widen the application of SCS to include larger numbers of patients with “intractable” back pain in the near future.
Written by Petra Rattue