Study Shows Spinal Neuromodulation Device Relieves Lower Back Pain

Patients suffering from lower back pain experienced better results from a novel spinal neuromodulation device rather than with conventional spinal cord stimulation (SCS), according to results of a study presented last week at the American Academy of Pain Medicine’s 27th Annual Meeting in Washington, D.C.

The results of the study were presented by Adnan Al-Kaisy, MB ChB FRCA, clinical lead of the Pain Management & Neuromodulation Centre, Guy’s & St. Thomas’ NHS Foundation Trust in London, England. Al-Kaisy and his colleagues conducted the study in the United Kingdom with 30 patients (some of whom have undergone spine surgery) who had an average back pain Visual Analog Score (VAS) of eight out of 10 and an average leg pain VAS score of six out of 10.

Researchers sequentially placed dual octapolar, percutaneous leads near the patients’ anatomic midline, between T8 and T11 (the thoracic area of the spinal column). A system designed by Menlo Park, Calif.-based Nevro Corp. to provide back pain relief was then connected to a rechargeable implantable pulse generator capable of delivering waveforms with frequencies up to 10 kilohertz. Nevro’s system consists of eight contact leads, an external stimulator device, a patient remote control, a clinician programmer device and accessories such as lead extensions. The system received CE Mark approval in Europe and is available in select locations there.

At three months, the average VAS score for back pain fell to 2.9 (p-value <0.05) and the average VAS score for leg pain fell to 2.2 (p-value <0.05). At six months the average back and leg pain VAS scores tumbled to 1.6 respectively. The study also used the Oswestry Disability Index (ODI) to measure ways in which back pain affected the patients’ daily lives. The ODI dropped from 61 (p-value <0.001) to 44 (p-value <0.001).

The study found that Nevro’s neuromodulation device significantly relieved back and leg pain at six months without producing paresthesia. It also improved patient function without movement-induced shocks as well as the quality of sleep for patients who used the system overnight. In addition, the system’s simple implantation eliminated the need for intra-operative paresthesia mapping.

The goal of spinal neuromodulation is to achieve paresthesia, which changes the pain sensation into a “pins and needles” or tingling sensation through stimulation of certain pain pathways, researchers noted. While SCS is the preferred treatment for patients suffering from lower back pain, providing paresthetic coverage of the lower back often is difficult and clinical results can be poor. Statistics show that 71 percent of SCS users also report uncomfortable stimulation.

For more than four decades, neuromodulators have struggled to find the right blend of techniques to electrical stimulation to relieve lower back pain. “To date there is no evidence that any of these techniques provide persistent long-term pain relief at the lower back,” Al-Kaisy said. “Nevro spinal cord stimulation is the cutting edge in implant technology which certainly is going to make a major difference in the management of persistent lower back pain. Using super high frequency stimulation, it suppresses the sparse fibers of the lower back, at the spinal cord level. Moreover, the frequency is so high the patient does not feel the ‘tingling sensation’ which some patients find extremely uncomfortable and distressing.”