Chronic Pain: Old Treatment Offers New Hope
The trial was effective in 74 of the patients, who then had surgery for permanent placement of an electrode and stimulator. Pain relief lasted for at least one year in 80% of these patients. Although the equipment sometimes malfunctioned after that, almost half of patients still had sufficient pain relief four years later to continue using the device.
As expected, success rate was highest -- almost 90% -- in those patients whose pain was caused by a damaged nerve. Success rate was 74% in patients with pain caused by nerve injury, and 72% in patients with pain caused by spinal cord damage.
Surprisingly, of the patients who had no obvious cause for their pain, 83% responded well to the stimulation. "As most patients with persistent back pain after multiple surgeries for slipped discs or arthritis have no clear reason for pain, spinal cord stimulation may offer new hope to them.
More good news was that outcome was no worse in patients who were receiving workers' compensation payments. Psychological factors -- such as an unconscious desire to avoid work or to collect benefits -- sometimes interferes with treatment of these individuals.
"We are in need of more studies like this one, looking at outcome predictors of our treatments for pain," says Milan Stojanovic, MD, director of the interventional pain program at Massachusetts General Hospital and Harvard Medical School. By selecting patients most likely to respond to treatment, doctors can improve the chances of success, Stojanovic tells WebMD.