Clinical Note Baclofen-enhanced spinal cord stimulation and intrathecal baclofen alone for neuropathic pain: Long-term outcome of a pilot study Go ¨ran Lind * , Gasto ´ n Schechtmann, Jaleh Winter, Bjo ¨ rn A. Meyerson, Bengt Linderoth Department of Neurosurgery, Karolinska University Hospital, SE-171 76 Stockholm, Sweden Received 31 August 2006; received in revised form 8 March 2007; accepted 10 March 2007 Available online 1 May 2007 Abstract In a previously published pilot study, we addressed the possibility to increase the effectiveness of spinal cord stimulation (SCS) applied for neuropathic pain by using adjunct pharmacological therapy. This combined treatment approach was a direct spin-off from animal experiments aiming at the exploration of transmitter and receptor mechanisms involved in the pain relieving effect of SCS. Out of 48 patients with neuropathic pain of peripheral origin responding poorly to SCS, seven received pumps for intra- thecal baclofen (GABA-B receptor agonist) delivery together with SCS, and four had pumps alone. In order to assess the long-term effect a follow-up has been performed, with an average, total treatment time of 67 months. At the follow-up the remaining nine patients still enjoy about the same pain relief as initially, but with a mean, further dose increase of about 30%. This study demon- strates that a deficient SCS effect in neuropathic pain may be considerably improved by intrathecal baclofen administration, and that this enhanced effect persists for a long-time. On-going and future animal studies may provide new and even more efficient phar- maceutical candidates for such combined therapy. Ó 2007 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved. Keywords: Neuropathic pain; Spinal cord stimulation; Baclofen; Human 1. Introduction Spinal cord stimulation (SCS) has been used for four decades to treat various pain conditions, such as neuro- pathic pain, ischemic extremity pain and angina pecto- ris. In spite of a satisfactory outcome in many patients with chronic neuropathic pain a significant number (about 30%) even of well-selected cases do not enjoy adequate pain relief. It also occurs that patients who have had satisfactory pain relief from SCS after some time experience a diminishing effect of the stimulation requiring additional treatment (Meyerson and Linde- roth, 2000; Simpson et al., 2005). In the 1990s, animal experiments demonstrated that intrathecal (i.t.) administration of the GABA-B receptor agonist baclofen in low doses enhanced the effect of SCS, and could even convert SCS non-responding ani- mals into good responders (Cui et al., 1996). A similar enhancing effect was also shown with other i.t. adminis- tered drugs (Cui et al., 1998; Cui et al., 1997b; Schecht- mann et al., 2004; Wallin et al., 2002). These results urged us to perform a clinical trial in patients with unsatisfactory response to SCS. The results from that study were published in 2004 in this journal (Lind et al., 2004). Forty-eight patients suffering 1090-3801/$32 Ó 2007 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ejpain.2007.03.011 * Corresponding author. Tel.: +46 8 51772041; fax: +46 8 307091. E-mail address: goran.lind@karolinska.se (G. Lind). www.EuropeanJournalPain.com Available online at www.sciencedirect.com European Journal of Pain 12 (2008) 132–136