Changes in quantitative sensory testing and patient perspectives following spinal cord stimulation for persistent spinal pain syndrome:an observational study with long-term follow-up

BACKGROUND: Spinal cord stimulation (SCS) can impact sensory, pain and tolerance thresholds in various ways, which can be accessed via quantitative sensory testing (QST). The objectives of this study were to (1) assess the subjective sensory responses using QST in patients following SCS therapy for PSPS and (2) to get a clinical impression of the results of SCS during an interview of these patients with PSPS and SCS during long term follow-up. METHODS: Forty patients with PSPS who received SCS treatment underwent QST via electrical and mechanical pressure stimuli. QST was performed at four different moments (1. pre-implantation SCS, 2. two weeks postoperatively, 3. three months after permanent SCS implantation and 4. six months after permanent SCS implantation. Patients' perspectives on pain, use of drugs and quality of life were assessed via semi-structured interviews during a follow-up between five and eleven years. RESULTS: We found statistical differences in the changes of sensory, pain and tolerance thresholds. A decrease in pain complaints and analgesics use were reported by the patients during follow-up. The quality of life in patients increased from three to eight (NRS 0 (worst QoL imaginable) -10 (best QoL imaginable) after receiving SCS. CONCLUSIONS: The increased thresholds on areas without pain or being covered by the SCS induced paresthesias may indicate that there are central changes contributing to these deviations in thresholds. The overall QoL in patients improved greatly after receiving SCS

The current role and future directions of imaging in failed back surgery syndrome patients: an educational review

Abstract Background Failed back surgery syndrome (FBSS) is an umbrella term referring to painful sensations experienced by patients after spinal surgery, mostly of neuropathic nature. Adequate treatment of FBSS is challenging, as its etiology is believed to be multifactorial and still not fully clarified. Accurate identification of the source of pain is difficult but pivotal to establish the most appropriate treatment strategy. Although the clinical utility of imaging in FBSS patients is still contentious, objective parameters are highly warranted to map different phenotypes of FBSS and tailor each subsequent therapy. Main body Since technological developments have weakened the applicability of prior research, this educational review outlined the recent evidence (i.e., from January 2005 onwards) after a systematic literature search. The state of the art on multiple imaging modalities in FBSS patients was reviewed. Future directions related to functional MRI and the development of imaging biomarkers have also been discussed. Conclusion Besides the fact that more imaging studies correlated with symptomatology in the postoperative setting are warranted, the current educational review outlined that contrast-enhanced MRI and MR neurography have been suggested as valuable imaging protocols to assess alterations in the spine of FBSS patients. The use of imaging biomarkers to study correlations between imaging features and symptomatology might hold future potential; however, more research is required before any promising hypotheses can be drawn

Spinal Cord Stimulation for Failed Back Surgery Syndrome: to Trial or Not to Trial?

Spinal cord stimulation (SCS) is a recommended therapy to treat failed back surgery syndrome (FBSS). A trial period is practiced to enhance patient selection. However, its fundamental evidence is limited, especially concerning long-term benefit and therapy safety. We compared the long-term (5.3 ± 4.0 years) clinical outcome and therapy safety of a trialed and nontrialed implantation strategy, including multidimensional variables and pain intensity fluctuations over time. A multicenter cohort analysis was performed in 2 comparable groups of FBSS patients. Regarding eligibility, patients had to be treated with SCS for at least 3 months. While the Trial group comprised patients who underwent an SCS implantation after a successful trial, the No-Trial group encompassed patients who underwent complete implantation within 1 session. The primary outcome measures were pain intensity scores and complications. The Trial and No-Trial groups consisted of 194 and 376 patients (N = 570), respectively. A statistically but not clinically significant difference in pain intensity (P =.003; effect = 0.506 (.172–.839)) was found in favor of the Trial group. No interaction between a time dependency effect and pain intensity was noted. Whereas trialed SCS patients were more likely to cease opioid usage (P =.003; OR =.509 (.326–.792)), patients in the No-Trial group endured fewer infections (P =.006; proportion difference =.43 (.007–.083)). Although the clinical relevance of our findings should be proven in future studies, this long-term real-world data study indicates that patient-centered assessments on whether an SCS trial should be performed have to be investigated. According to the current ambiguous evidence, SCS trials should be considered on a case-by-case basis. Perspective: The currently available comparative evidence, together with our results, remains ambiguous on which SCS implantation strategy might be deemed superior. An SCS trial should be considered on a case-by-case basis, for which further investigation of its clinical utility in certain patient populations or character traits is warranted