High-Dose Spinal Cord Stimulation for Treatment of Chronic Low Back Pain and Leg Pain in Patients With FBSS, 12-Month Results: A Prospective Pilot Study

OBJECTIVES: To investigate the long-term effect of high-dose spinal cord stimulation (HD-SCS) in patients with chronic refractory low back and leg pain due to failed back surgery syndrome (FBSS). STUDY DESIGN: Prospective case series; pilot study. MATERIALS AND METHODS: Patients with chronic low back and leg pain (CBLP) due to failed back surgery syndrome (FBSS) were screened for SCS according to the Dutch Neuromodulation Society guidelines. Patients with a pain score of >50 (on a visual analogue scale from 0 to 100) for both low back and leg pain, were selected for participation in this study. During intraoperative screening one or two electrodes were implanted to ensure adequate paresthesia coverage of the back and leg pain area. During the 14 days trial period patients received two programs: a conventional or low-dose (LD) program with 30 Hz; 390 musec and a high-dose (HD) program with 420 Hz, 400 musec. They all started with LD-SCS and changed to HD-SCS after three days. If patients reported more than 50% pain relief with either program a rechargeable neurostimulator was implanted for permanent SCS. The scores for low back pain and leg pain were recorded separately. Other therapy related outcomes that were collected are pain medication use, Quebec back pain disability scale (QBPDS), patient satisfaction, employment status, stimulation settings, and adverse events. We present the 6- and 12-months results. Results are presented as mean +/- SD. RESULTS: Thirteen patients, nine females and four males (mean age: 49.7 +/- 8.1 years), were included between July 2015 and March 2016. Eleven patients responded to SCS during the trial period and were implanted with a neurostimulator. Most patients preferred HD-SCS over LD-SCS and the overall use of HD-SCS increased over time. At 6 to 12 months follow-up, two patients discontinued the study. In one patient low back pain returned despite optimal stimulation settings. The second patient was neither satisfied with LD nor HD and had the system explanted. VAS Leg pain at baseline was 71.2 +/- 33.8 and reduced to 25.7 +/- 24.0 at 6 months and 23.4 +/- 32.0 at 12 months. VAS Back pain at baseline was 66.7 +/- 33.2 and reduced to 36.8 +/- 41.6 at 6 months and 26.1 +/- 33.2 at 12 months. Pain medication was significantly reduced and QBPDS improved from 59.2 +/- 12.2 at baseline to 44.1 +/- 13.7 at 12 months. Five patients returned to work and overall patient satisfaction at the end of the study was high. CONCLUSION: This pilot study shows promising results of offering HD-SCS in addition to LD-SCS for treatment of chronic back and leg pain in patients with failed back surgery syndrome

Spinal Cord Stimulation With Additional Peripheral Nerve/Field Stimulation Versus Spinal Cord Stimulation Alone on Back Pain and Quality of Life in Patients With Persistent Spinal Pain Syndrome.

INTRODUCTION: Persistent spinal pain syndrome (PSPS) or failed back surgery syndrome (FBSS) refers to new or persistent pain following spinal surgery for back or leg pain in a subset of patients. Spinal cord stimulation (SCS) is a neuromodulation technique that can be considered in patients with predominant leg pain refractory to conservative treatment. Patients with predominant low back pain benefit less from SCS. Another neuromodulation technique for treatment of chronic low back pain is subcutaneous stimulation or peripheral nerve field stimulation (PNFS). We investigated the effect of SCS with additional PNFS on pain and quality of life of patients with PSPS compared with that of SCS alone after 12 months. MATERIALS AND METHODS: This is a comparative study of patients with PSPS who responded to treatment with either SCS + PNFS or SCS only following a multicenter randomized clinical trial protocol. In total, 75 patients completed the 12-month follow-up: 21 in the SCS-only group and 54 in the SCS + PNFS group. Outcome measures were pain (visual analog scale), quality of life (36-Item Short Form Survey [SF-36]), anxiety and depression (Hospital Anxiety and Depression Scale [HADS]), overall health (EuroQol Five-Dimension [EQ-5D]), disability (Oswestry Disability Index [ODI]), and pain assessed by the McGill questionnaire. RESULTS: There were no significant differences in baseline characteristics between the two groups. Both groups showed a significant reduction in back and leg pain at 12 months compared with baseline measurements. No significant differences were found between the groups in effect on both primary (pain) and secondary parameters (SF-36, HADS, EQ-5D, ODI, and McGill pain). CONCLUSION: In a subgroup of patients with chronic back and leg pain, SCS alone provided similar long-term pain relief and quality-of-life improvement as PNFS in addition to SCS. In patients with refractory low back pain not responding to SCS alone, adding PNFS should be recommended. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT01776749