The performance and safety of an implantable spinal cord stimulation system in patients with chronic pain: a 5-year study.

Reliability and ease of use of the Itrel 3 System (Medtronic Inc., Minneapolis, MN) were prospectively assessed over 5 years in patients with a range of pain syndromes (mainly low back and/or leg pain, or ischemic pain due to peripheral vascular disease). The longevity of the implantable pulse generator (IPG) battery, the frequency with which system settings were changed, and the ease of use of the EZ patient programmer were assessed. Data on adverse events, pain relief, and patient satisfaction with therapy were also collected. Following a screening procedure, 85 systems were implanted in 84 patients. Twenty-four patients were withdrawn prematurely and, in an additional 32 cases, end of battery life was reached before the end of the study. The survival curve for the IPG batteries showed that approximately 50% are expected to last up to the sixth year. No device failures or unanticipated device-related adverse events were reported. At least 90% of patients considered the EZ patient programmer easy to use. System settings were stable over time. The intensity and duration of pain were reduced significantly and patient satisfaction with therapy was high. We conclude that the Itrel 3 System performed well over 5 years and was easy to use. Its safety and effectiveness for the relief of chronic intractable pain of the trunk or limbs were also confirmed.