Background & Aims
Spinal cord stimulation (SCS) is a NICE recommended treatment in patients with intractable neuropathic pain. Traditionally the therapy is used in patients who have chronic neuropathic pain following failed back surgery syndrome (FBSS). There is emerging evidence of SCS being used in patients with intractable neuropathic back pain who have not undergone previous spinal surgery (PSPS Type 1). (1,2,3) The aim of this study is to investigate the long term effect of SCS on functionality, quality of life and adverse events in the patients comprising the study population.
Methods
After ethics approval (NRES 18-LO-0365, NCT NCT03818074) patients with intractable neuropathic pain (n=30) due to undergo SCS with Boston Scientific Wavewriter as part of their standard treatment were recruited. All patients underwent MDT assessment (Neurosurgeon, Pain Physician and Psychologist) to rule out any potential surgical or psychological confounders. Pain scores (NRS) and data from self-report questionnaires – Oswestry Disability Index (ODI), Pain and Sleep Questionnaire (PSQ), EQ-5D-5L and economical resource questionnaire; was collected pre-implant and at 1 month, 3 months, 6 months, 12 months and 24 months post-implant.
Results
Mean NRS for back, leg and overall decreased from 7.77, 7.23 and 7.46 respectively at baseline (n=30) to 4.18, 3.47 and 4.03 respectively at 12 months (p = 0.0011, p < 0.0001 and p < 0.0001) (n=19) and 3.5, 3.00 and 3.25 respectively at 24 months (p = 0.0319, p = 0.0044 and p = 0.0096) (n=8). Mean ODI score improved from 55.1 at baseline (n=30) to 42.5 at 12 months (p = 0.0218) (n=17) and 27.2 at 24 months (p = 0.1259) (n=7). There was also an improvement in mean EQ-5D-5L index from 0.35 at baseline (n=30) to 0.66 at 12 months (p = 0.0008) (n=17) and 0.85 at 24 months (p < 0.0001) (n=7). There was also a significant improvement in mean EQ-5D-5L VAS and PSQ-3 scores. MQS III (Medication Quantification Score) calculated for pain medicines fell from 17.48 at baseline (n=30) to 10.74 at 12 months (p = 0.0404) (n=19). 11 patients in total were withdrawn (3 lead migration, 4 high impedance, 3 loss of therapy, 1 personal circumstances).
Conclusions
This long term follow-up demonstrates marked improvements in pain severity, sleep, self-efficacy and quality of life parameters in PSPS type-1 patient population that were shown to be maintained at 24 months post implant. Careful patient selection remains pivotal in outcomes to minimise explant rates. In line with previous studies, SCS can be an advance spine-surgery sparing pain management option for this group of patients where surgery would not be appropriate based on pathology or risk/benefit.(1,2,3)
References
1.Al-Kaisy, A. et al. (2018) ‘Long-term improvements in chronic axial low back pain patients without previous spinal surgery: A cohort analysis of 10-KHz high-frequency spinal cord stimulation over 36?months’, Pain Medicine, 19(6), pp. 1219–1226. doi:10.1093/pm/pnx237.
2.Mehta, V. et al. (2021) ‘Effectiveness of high dose spinal cord stimulation for non?surgical intractable lumbar Radiculopathy ? hidens study’, Pain Practice, 22(2), pp. 233–247. doi:10.1111/papr.13087.
3.Eckermann, J.M. et al. (2022) ‘Systematic literature review of spinal cord stimulation in patients with chronic back pain without prior spine surgery’, Neuromodulation: Technology at the Neural Interface, 25(5), pp. 648–656. doi:10.1111/ner.13519.
Presenting Author
Kavita Poply
Poster Authors
Topics
- Evidence, Clinical Trials, Systematic Review, Guidelines, and Implementation Science