Efficacy of Simultaneous Usage of Spinal Cord Stimulation and Intrathecal Therapy for Nonmalignant Chronic Neuropathic Pain

Abstract

Some patients with chronic pain and implanted spinal cord stimulators or intrathecal (IT) pumps fail to obtain significant pain relief. The use of dual modality treatment with both therapies is understudied. This study evaluated comprehensive outcomes in this patient population and reported outcomes primarily using IT ziconotide. We retrospectively analyzed 11 patients with chronic pain treated with both spinal cord stimulation and IT therapy. When a primary treatment failed to achieve significant pain relief, a secondary device was trialed and implanted. Pain severity (measured by a numeric rating scale) was assessed by the change from baseline to after the first and second intervention. In a subset of patients (n= 6), quality-of-life metrics were also assessed. Outcome measures were analyzed closest to the 1-year follow-up date after implantation of the first modality and then at the most recent follow-up after implantation of the second modality. Spinal cord stimulation leads were percutaneous (n= 2) or paddles (n= 9) and commonly covered T8-10. IT medication included ziconotide (n= 8), baclofen (n= 1), hydromorphone (n= 1), and morphine/clonidine (n= 1). There was a mean of 19.64 ± 3.17 months between primary and secondary intervention. There was a significant improvement in pain severity from baseline to implantation of the second modality (P= 0.032) at a mean follow-up of 50.18 ± 11.83 months. Dual modality therapy is a potential treatment option in patients who have lost efficacy with a single neuromodulation modality. Further study is required to identify potential responders and nonresponders.