Differential diagnosis between recurrent disc herniation and granulation tissue after lumbar disc herniation Surgery: Qualitative analysis on MRI scans

BACKGROUND

Recurrence of disc herniation is a prevalent late-term complication among patients surgically treated for lumbar disc herniation. Differential diagnosis between recurrent disc herniation and granulation tissue can be achieved through signal intensity measurements on T2-weighted MRI examinations. This study aims to examine cases operated on for recurrence of lumbar disc herniation, assessing those presenting with either disc recurrence or granulation tissue. The objective is to demonstrate that differential diagnosis can be facilitated through signal intensity value measurements and radiological findings in MRI examinations of patients with disc herniation recurrence and granulation tissue.

METHODS

Analysis involved reviewing lumbar MRI T2 sequences of patients operated on with a presumptive diagnosis of lumbar disc herniation recurrence. Mean T2 signal intensity values in preoperative MRI images of cases with disc herniation recurrence and granulation tissue were examined and recorded on the Picture Archiving and Communication System. Mean T2 signal intensity values of recurrent disc herniation and granulation tissue were then compared.

RESULTS

Among the patients who underwent surgery, disc herniation recurrence was observed in 135 cases, while granulation tissue was found in 12 patients (8.89 %). The preopreative mean T2 signal intensity value for disc herniation was recorded as 54.82 ± 2.42, whereas the mean T2 signal intensity value for granulation tissue was 205.96 ± 5.62.

CONCLUSIONS

T2 sequences in MRI examinations offer the clearest evaluation of disc herniations. Mean T2 signal intensity value measurements conducted on the PACS system can aid in differentiating between recurrent disc herniation and granulation tissue. These findings serve to inform surgical protocols during the preoperative phase.

Functional Stimulation and Imaging to Predict Neuromodulation of Chronic Low Back Pain

Back pain is one of the most common aversive sensations in human experience. Pain is not limited to the sensory transduction of tissue damage; rather, it encompasses a range of nervous system activities including lateral modulation, long-distance transmission, encoding, and decoding. Although spine surgery may address peripheral pain generators directly, aberrant signals along canonical aversive pathways and maladaptive influence of affective and cognitive states can result in persistent subjective pain refractory to classical surgical intervention. The clinical identification of who will benefit from surgery-and who will not-is increasingly grounded in neurophysiology.

Long-term efficacy of spinal cord stimulation for chronic primary neuropathic pain in the contemporary era: a systematic review and meta-analysis

INTRODUCTION

Spinal cord stimulation (SCS) is a modern neuromodulation technique extensively proven to be an effective modality for treatment of chronic neuropathic pain. It has been mainly studied for complex regional pain syndrome (CRPS) and failed back surgery syndrome (FBSS) and recent data almost uniformly establishes its statistically significant positive therapeutic results. It has also been compared with other available treatment modalities across various studies. However, long term data on maintenance of its efficacious potential remains less explored. Few studies have reported data on long follow-up times (>= 12 months) and have compared its efficacy with other treatment options for chronic pain, respectively. Our study pools and analyzes the available data and compares SCS with other treatment options. It also analyzes the efficacy of SCS in long term management of patients with chronic pain.

EVIDENCE ACQUISITION

We reviewed all the data available on MEDLINE, Embase and Cochrane CENTRAL using a search strategy designed to fit our pre-set inclusion and exclusion criteria. Both single-arm and double-arm studies were included. The primary outcome was defined as decrease of visual analogue scale (VAS) by >50% at 6, 12 and/or 24 months after SCS.

EVIDENCE SYNTHESIS

According to the pooled data of double-arm studies, SCS has unanimously proven its superiority over other treatment options at 6 months follow-up; however it fails to prove statistically significant difference in results at longer treatment intervals. Dorsal root ganglion stimulation, a relatively recent technique with the same underlying physiologic mechanisms as SCS, showed far more promising results than SCS. Single-arm studies show around 70% patients experiencing greater than 50% reduction in their VAS scores at 6 and 12 months.

CONCLUSIONS

SCS is a viable option for management of chronic neuropathic pain secondary to FBSS and CRPS. However, data available for its long term efficacy remains scarce and show no further statistically significant results.

Gait analysis, trunk movements, and electromyographic patterns after minimally invasive spine surgery for lumbar instability: An observational prospective study

Objective

The aim of the present study was to investigate trunk kinematics and spine muscle activation during walking after minimally invasive surgery in patients with L4-L5 degenerative spondylolisthesis suffering from lumbar instability (LI).

Methods

Eleven patients suffering from LI and 13 healthy controls (HC) were enrolled. Trunk kinematics and spine muscle activation patterns during walking were collected. Maximal trunk ranges of motion were also recorded from standing position. Assessments were performed pre-operatively (T0), 1 month (T1) and 3 months (T2) after MIS.

Results

We found significant improvement in spine muscle activation during walking at T2 compared to T0, mainly involving right/left symmetry at the operated level (L4-L5) and up-down synchronization from L3 to S1. Significant improvements in trunk rotation nearing to the HC group during walking were also found at T2 after surgery, though no changes were observed in the maximal range of motion of the trunk during standing. Furthermore, trunk rotation improvement correlated with a lower grade of residual disability.

Conclusions

Our findings indicate that trunk rotation improves after surgery, and impaired aspects of spine muscle activation can be improved with surgery. These biomechanical parameters could represent novel tools for monitoring the effect of surgery in LI and preventing impaired spine mobility and muscle activation.

Effectiveness of Cognitive Functional Therapy Versus Core Exercises and Manual Therapy in Patients With Chronic Low Back Pain After Spinal Surgery: Randomized Controlled Trial

OBJECTIVE

Our aim was to investigate whether cognitive functional therapy (CFT) was more effective than core exercises and manual therapy (CORE-MT) in improving pain and function for patients with chronic low back pain after spinal surgery.

METHODS

This study was a randomized controlled superiority trial in a university hospital and a private physical therapist clinic in Santa Catarina, Brazil. Eighty participants who were 18 to 75 years old and had chronic low back pain after spinal surgery received 4 to 12 treatment sessions of CFT or CORE-MT once per week for a maximum period of 12 weeks. Primary outcomes were pain intensity (numeric pain rating scale, scored from 0 to 10) and function (Patient-Specific Functional Scale, scored from 0 to 10) after intervention.

RESULTS

We obtained primary outcome data for 75 participants (93.7%). CFT was more effective, with a large effect size, than CORE-MT in reducing pain intensity (mean difference [MD] = 2.42; 95% CI = 1.69-3.14; effect size [d] = 0.85) and improving function (MD = -2.47; 95% CI = -3.08 to -1.87; effect size = 0.95) after intervention (mean = 10.4 weeks [standard deviation = 2.17] after the beginning of treatment). The differences were maintained at 22 weeks for pain intensity (MD = 1.64; 95% CI = 0.98-2.3; effect size = 0.68) and function (MD = -2.01; 95% CI = -2.6 to -1.41; effect size = 0.81).

CONCLUSION

CFT was more effective than CORE-MT, with large effect sizes, and may be an option for patients with chronic low back pain after spinal surgery.

IMPACT

CFT reduces pain and improves function, with large effect sizes, compared with CORE-MT. The difference between CFT and CORE-MT was sustained at the midterm follow-up. Treatment with CFT may be an option for patients with chronic low back pain after spinal surgery.

A Bibliometric Analysis of Top-Cited Journal Articles Related to Neuromodulation for Chronic Pain

OBJECTIVES

Since its foundation in the 1960s, neuromodulation has become an increasingly used treatment option for chronic pain. This bibliometric analysis examines the most cited research in this field with the aim of uncovering existing trends and future directions.

MATERIALS AND METHODS

Clarivate's Web of Science data base was searched for the top 25 most cited studies focusing on neuromodulation for chronic pain. Various bibliometric parameters were then extracted and analyzed. Randomized controlled trials (RCTs) were compared with non-RCTs.

RESULTS

The top 25 articles had a mean of 347 citations and 22.2 citations per year, with more recent articles having a higher citation rate. Most were published in the last two decades and predominantly originated from the United States. There were 13 RCTs, which were significantly more recent (p = 0.004) and more cited per year (p = 0.001) than the 12 non-RCTs. Sources included 15 journals with a mean impact factor of 13.896. The most studied modality was spinal cord stimulation with 20 articles (76.9%), followed by intrathecal drug delivery (15.4%), dorsal root ganglion stimulation (3.8%), and peripheral nerve stimulation (3.8%).

CONCLUSIONS

Analysis of the most cited articles on neuromodulation reveals a focal shift from historical reports to innovative RCTs that have increasingly guided pain practice in the recent years. As novel techniques and technologies continue to develop, high-quality evidence coupled with broadening indications will likely direct further expansion of this field.

Long-Term Outcome in Patients With Spinal Cord Stimulation for Failed Back Surgery Syndrome: A 20-Year Audit of a Single Center

STUDY DESIGN

This is a retrospective, observational study.

INTRODUCTION

Spinal cord stimulation (SCS) has found its application in chronic pain treatment, with failed back surgery syndrome (FBSS) as one of the most important indications. However, to date, little is known about the long-term effectiveness of the treatment. The aim of this study is to analyze retrospectively the long-term outcomes of SCS treatment in a single multidisciplinary pain center on predominant radicular pain, using devices of a single manufacturer.

MATERIALS AND METHODS

Patient data on overall patient satisfaction, pain intensity, and adverse events were retrospectively collected in our clinical practice between January 1998 and January 2018, for 191 patients who received a permanent SCS implant. Secondary health measures included the influence of opioid and nicotine use on pain reduction after therapy.

RESULTS

The trial-to-implant ratio was 93.6%. At a mean follow-up of 10.6 years, 78.5% of the patients were satisfied with the treatment outcome, with a significant pain reduction of an average three points on a Numeric Rating Scale. Opioid and nicotine usage did not have a significant link with the pain reduction one year after the treatment. Furthermore, devices had an average battery lifespan of 8.4 years. A total of 248 revisions were recorded. A total of 24 patients (11.7%) acquired an infection; 7 of 204 patients had an infection during the trial period, 2 of 191 patients had an infection in the first postoperative year, and 15 of 191 patients had an infection after the first year. The average time to infection, if not in the first year, was 10.1 years.

CONCLUSIONS

A successful long-term outcome regarding pain relief in patients with predominant radicular pain due to FBSS is established with SCS therapy.

Incidence and risk factors of spinal cord stimulation for persistent or recurrent pain after lumbar spine surgery: a population-based study

PURPOSE

This study aims to elucidate the incidence of and independent risk factors for spinal cord stimulator implantations for patients who underwent lumbar spine surgery.

METHODS

The PERFormance, Effectiveness, and Cost of Treatment (PERFECT) episodes database, which was established for selected diseases and procedures in Finland, includes all patients who underwent lumbar spine surgery for degenerative spine conditions or spinal cord stimulation (SCS) in Finland from 1986 to 2018. The data on age, sex, hospital diagnoses, surgical procedures, and causes of death were imported from the Finnish national registers into the PERFECT database.

RESULTS

Between 1986 and 2018, 157,824 patients had their first lumbar spine procedure and for 1769 (1.1%) of them, a subsequent SCS procedure was observed during the follow-up. The cumulative incidence of SCS for persistent or recurrent pain after lumbar disk herniation, spinal stenosis, degenerative disk disease, and spondylolysis and spondylolisthesis surgery at 15 years was 1.2%, 1.0%, 2.7%, and 2.6% respectively. At 15 years, the cumulative incidence of SCS for persistent or recurrent pain after lumbar spine surgery after five or more lumbar spinal operations was 11.9%.

CONCLUSION

Repeated surgery was the most prominent significant risk factor for SCS for persistent or recurrent pain after lumbar spine surgery. The risk of SCS for persistent or recurrent pain after lumbar spine surgery increases significantly along with the number of lumbar spine procedures. When considering repeated lumbar spine surgery, careful evaluation of treatment options should take place to ensure good patient outcomes.

Evaluation of Sagittal Spinopelvic Balance in Spinal Cord Stimulator Patients

OBJECTIVE

Spinal cord stimulation (SCS) has become a popular nonopioid pain intervention. However, the treatment failure rate for SCS remains significantly high and many of these patients have poor sagittal spinopelvic balance, which has been found to correlate with increased pain and decreased quality of life. The purpose of this study was to determine if poor sagittal alignment is correlated with SCS treatment failure.

MATERIALS AND METHODS

Comparative retrospective analysis was performed between two cohorts of patients who had undergone SCS placement, those who had either subsequent removal of their SCS system (representing a treatment failure cohort) and those that underwent generator replacement (representing a successful treatment cohort). The electronic medical record was used to collect demographic and surgical characteristics, which included radiographic measurements of lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Also included were data on pain medication usage including opioid and nonopioid therapies.

RESULTS

Eighty-one patients met inclusion criteria, 31 had complete removal, and 50 had generator replacements. Measurement of sagittal balance parameters demonstrated that many patients had poor alignment, with 34 outside normal range for LL (10 vs 24 in removal and replacement cohorts, respectively), 30 for PI (12 [38.7%] vs 18 [36.0%]), 46 for PT (18 [58.1%] vs 28 [56.0%]), 38 for SS (18 [58.1%] vs 20 [40.0%]), and 39 for PI-LL mismatch (14 [45.2%] vs 25 [50.0%]). There were no significant differences in sagittal alignment parameters between the two cohorts.

CONCLUSIONS

This retrospective cohort analysis of SCS patients did not demonstrate any relationship between poor sagittal alignment and failure of SCS therapy. Further studies of larger databases should be performed to determine how many patients ultimately go on to have additional structural spinal surgery after failure of SCS and whether or not those patients go on to have positive outcomes.

Ethical Considerations in the Implantation of Neuromodulatory Devices

OBJECTIVES

Neuromodulatory devices are increasingly used by neurosurgeons to manage a variety of chronic conditions. Given their potential benefits, it is imperative to create clear ethical guidelines for the use of these devices. We present a tiered ethical framework for neurosurgeon recommendations for the use of neuromodulatory devices.

MATERIALS AND METHODS

We conducted a literature review to identify factors neurosurgeons should consider when choosing to offer a neuromodulatory device to a patient.

RESULTS

Neurosurgeons must weigh reductions in debilitating symptoms, improved functionality, and preserved quality of life against risks for intraoperative complications and adverse events due to stimulation or the device itself. Neurosurgeons must also evaluate whether patients and families will maintain responsibility for the management of neuromodulatory devices. Consideration of these factors should occur on an axis of resource allocation, ranging from provision of neuromodulatory devices to those with greatest potential benefit in resource-limited settings to provision of neuromodulatory devices to all patients with indications in contexts without resource limitations. Neurosurgeons must also take action to promote device effectiveness throughout the duration of care.

CONCLUSIONS

Weighing risks and benefits of providing neuromodulatory devices and assessing ability to remain responsible for the devices on the level of the individual patient indicate which patients are most likely to achieve benefit from these devices. Consideration of these factors on an axis of resource allocation will allow for optimal provision of neuromodulatory devices to patients in settings of varied resources. Neurosurgeons play a primary role in promoting the effectiveness of these devices.

Effectiveness and safety of motion style acupuncture treatment of the pelvic joint for herniated lumbar disc with radiating pain: A prospective, observational pilot study

CONTEXT

Conservative treatment is effective for treating and managing herniated lumbar disc with radiating leg pain.

OBJECTIVES

To investigate the effects of motion style acupuncture treatment (MSAT) on the pelvic joint for this condition.

DESIGN

This prospective observational study was a pilot study for a future randomized, controlled trial (RCT).

SETTING

[masked for review].

PATIENTS/INTERVENTIONS

We enroled 40 patients and allocated them to two groups (both n = 20). Groups 1 and 2 received integrative Korean medicine treatment (KMT) and integrative KMT with MSAT for pelvic joint, respectively. Primary outcome was the Numeric Rating Scale (NRS) score for low back pain. Secondary outcomes were the Oswestry Disability Index (ODI), Visual analogue Scale (VAS), and EuroQol 5-Dimension-5-level (EQ-5D-5 L) scores. Efficacy was assessed by comparing the baseline and Day 4 results. Safety was assessed based on the frequency and severity of all adverse events.

RESULTS

On Day 14, except for ODI in Group 1, the NRS, VAS, and EQ-5D-5 L scores showed significant improvements in both groups. On Day 90, both groups showed significant improvements in the NRS, ODI, and EQ-5D-5 L scores. There was a significant between-group difference in the NRS score on Day 7. On Day 14, Group 2 had a significantly lower VAS score for radiating leg pain than Group 1. Twelve patients reported adverse events associated with integrative KMT; however, there was no association with pelvic joint MSAT.

CONCLUSION

Adding MSAT for pelvic joint to conventional integrative KMT may ameliorate radiating leg pain and improve the quality of life.

Persistent Spinal Pain Syndrome: A Proposal for Failed Back Surgery Syndrome and ICD-11

Objective

For many medical professionals dealing with patients with persistent pain following spine surgery, the term Failed back surgery syndrome (FBSS) as a diagnostic label is inadequate, misleading, and potentially troublesome. It misrepresents causation. Alternative terms have been suggested, but none has replaced FBSS. The International Association for the Study of Pain (IASP) published a revised classification of chronic pain, as part of the new International Classification of Diseases (ICD-11), which has been accepted by the World Health Organization (WHO). This includes the term Chronic pain after spinal surgery (CPSS), which is suggested as a replacement for FBSS.

Methods

This article provides arguments and rationale for a replacement definition. In order to propose a broadly applicable yet more precise and clinically informative term, an international group of experts was established.

Results

14 candidate replacement terms were considered and ranked. The application of agreed criteria reduced this to a shortlist of four. A preferred option—Persistent spinal pain syndrome—was selected by a structured workshop and Delphi process. We provide rationale for using Persistent spinal pain syndrome and a schema for its incorporation into ICD-11. We propose the adoption of this term would strengthen the new ICD-11 classification.

Conclusions

This project is important to those in the fields of pain management, spine surgery, and neuromodulation, as well as patients labeled with FBSS. Through a shift in perspective, it could facilitate the application of the new ICD-11 classification and allow clearer discussion among medical professionals, industry, funding organizations, academia, and the legal profession.

The Effectiveness of Spinal Cord Stimulation for the Treatment of Axial Low Back Pain: A Systematic Review with Narrative Synthesis

OBJECTIVE

Determine the effectiveness of spinal cord stimulation (SCS) for the treatment of axial low back pain (LBP) with or without leg pain.

DESIGN

Systematic review.

SUBJECTS

Persons aged ≥18 with axial LBP with or without accompanying leg pain.

INTERVENTION

Traditional low-frequency, burst, or high-frequency SCS.

COMPARISON

Sham, active standard of care treatment, or none.

OUTCOMES

The primary outcome was ≥50% pain improvement, and the secondary outcome was functional improvement measured six or more months after treatment intervention.

METHODS

Publications in PubMed, MEDLINE, and Cochrane databases were reviewed through September 19, 2019. Randomized or nonrandomized comparative studies and nonrandomized studies without internal controls were included. The Cochrane Risk of Bias Tool and GRADE system were used to assess individual study characteristics and overall quality.

RESULTS

Query identified 262 publications; 17 were suitable for inclusion. For high-frequency SCS, the only level 1 study showed that 79% (95% confidence interval = 70-87%) of patients reported ≥50% pain improvement. For low-frequency SCS, the only level 1 study reported no categorical data for axial LBP-specific outcomes; axial LBP improved by a mean 14 mm on the visual analog scale at six months. Meta-analysis was not performed due to study heterogeneity.

CONCLUSIONS

According to GRADE, there is low-quality evidence that high-frequency SCS compared with low-frequency SCS is effective in patients with axial LBP with concomitant leg pain. There is very low-quality evidence for low-frequency SCS for the treatment of axial LBP in patients with concomitant leg pain. There is insufficient evidence addressing the effectiveness of burst SCS to apply a GRADE rating.

Spinal cord stimulation for the treatment of neuropathic pain: expert opinion and 5-year outlook

INTRODUCTION

Spinal cord stimulation (SCS) is an effective treatment for chronic, intractable neuropathic pain. There have been relatively few high-level studies that suggest its unequivocal use. The decay of stimulation efficacy over time have opened opportunity for the entrance of new pulse trains and waveforms.

AREAS COVERED

In this state-of-the-art review, we focused on many of the major studies published in the last 10 years that were considered level one evidence. A retrospective narrative approach was taken to conceptualize foundation studies as they pertain to current evidence. A special focus was taken on reported safety outcomes in comparison to foundation studies especially as they pertain to our 5-year outlook on the use of spinal cord stimulation.

EXPERT OPINION

We find there are still significant limitations in the body of reviewed evidence and suggest that long-term data beyond 24 months are lacking in the literature. In addition, adverse event rates, device explantation rates and the sham effect looms as important concepts to address in the future in spite of the existing novel stimulation paradigms.

Treatment of a Large Cohort of Veterans Experiencing Musculoskeletal Disorders with Spinal Cord Stimulation in the Veterans Health Administration: Veteran Characteristics and Outcomes

OBJECTIVE

Spinal cord stimulator (SCS) implantation is used to treat chronic pain, including painful musculoskeletal disorders (MSDs). This study examined the characteristics and outcomes of veterans receiving SCSs in Veterans Health Administration (VHA) facilities.

METHODS

The sample was drawn from the MSD Cohort and limited to three MSDs with the highest number of implants (N=815,475). There were 1490 veterans with these conditions who received SCS implants from 2000 to 2012, of which 95% (n=1414) had pain intensity numeric rating scale (NRS) data both pre- and post-implant.

RESULTS

Veterans who were 35-44 years old, White, and married reported higher pain NRS ratings, had comorbid inclusion diagnoses, had no medical comorbidities, had a BMI 25-29.9, or had a depressive disorder diagnosis were more likely to receive an SCS. Veterans 55+ years old or with an alcohol or substance use disorder were less likely to receive an SCS. Over 90% of those receiving an SCS were prescribed opioids in the year prior to implant. Veterans who had a presurgical pain score ≥4 had a clinically meaningful decrease in their pain score in the year following their 90-day recovery period (Day 91-456) greater than expected by chance alone. Similarly, there was a significant decrease in the percent of veterans receiving opioid therapy (92.4% vs 86.6%, p<0.0001) and a significant overall decrease in opioid dose [morphine equivalent dose per day (MEDD) =26.48 vs MEDD=22.59, p<0.0003].

CONCLUSION

Results offer evidence of benefit for some veterans with the examined conditions. Given known risks of opioid therapy, the reduction is an important potential benefit of SCS implants.

Effects of Scrambler Therapy in Patients with Failed Back Surgery Syndromes and Factors Associated with Depression Affecting Pain before and after the Therapy

Objectives

To report the effects of scrambler therapy in patients diagnosed with failed back surgery syndromes and to analyze the factors affecting pain before and after the therapy.

Methods

This study included 26 patients (12 males and 14 females). The Oswestry Disability Index (ODI) and Brief Pain Inventory (BPI) before and after scrambler therapy, Beck Depression Inventory (BDI) score before therapy, and residual pain after therapy were assessed. The changes in the ODI, BPI, and residual pain before and after the therapy were analyzed using the Wilcoxon signed rank test. Spearman correlation analysis and Fisher's exact test were used to confirm the correlation between BDI and other factors. Multiple regression analysis was used to identify independent factors predicting residual pain, posttherapy ODI, and posttherapy BPI.

Results

The ODI changed from 25.69 ± 7.98 to 21.80 ± 9.41 (p < 0.05), and the BPI changed from 68.96 ± 18.00 to 61.62 ± 20.27 after scrambler therapy (p < 0.05). In addition, residual pain changed from 100 to 76.15 (p < 0.05). The BDI was negatively correlated with the duration of scrambler therapy and positively correlated with the initial OPD and BPI. In multiple regression analysis, residual pain was significantly correlated with the BDI (p < 0.05).

Conclusion

Scrambler therapy can be used to change the total scores of the ODI and BPI after 5 sessions of treatment. Also, residual pain was significantly related to the BDI. Clinical significance of depression severity on pain should be further investigated via prospective studies.

Sensor driven-position adaptive versus conventional spinal cord stimulation in failed back surgery syndrome: a retrospective case series

Background

Failed back surgery syndrome (FBSS) is a common problem affecting 20–40% of cases undergoing spine surgeries. Spinal cord stimulation (SCS) has been shown to be an efficient and relatively safe treatment in managing many intractable chronic pain syndromes.

Objectives

This study compares the efficacy and safety of MR-compatible sensor driven-position adaptive SCS and conventional SCS in treating FBSS.

Methods

This is a retrospective case series of 120 consecutive FBSS patients who underwent SCS between February 2011 and March 2018. Pain levels, analgesic/opioid use, and sleep problems were assessed before and 3 months after the procedure in patients who received either conventional SCS (group 1; n = 62) or sensor-driven position adaptive SCS (group 2; n = 34). The degree of patient satisfaction, the change in the activities of daily living (ADLs) together with the rate of complications were compared in both treatment groups.

Results

The two treatment groups were homogenous at baseline. Patients in both groups improved significantly regarding pain, opioid consumption, sleep, and ADLs. The magnitude of improvement was statistically higher in group 2. An absolute reduction of 6 points on the VAS in patients who received position adaptive SCS vs a 3.3 point reduction in conventional SCS cases (p < 0.0001). Half of the patients in group 2 (n = 17) showed excellent satisfaction after the procedure versus 14.5% of cases in group 1 (n = 9).

Conclusion

SCS is an efficient and reliable treatment in FBSS. MR-compatible sensor driven-position adaptive SCS can be a more effective treatment in this patient group.

Association Between Pain Scores and Successful Spinal Cord Stimulator Implantation

INTRODUCTION

Determining reduction in pain score during spinal cord stimulation (SCS) trial is important prior to permanent SCS implantation. However, this association remains elusive. We investigate the association between post-SCS pain scores and successful permanent SCS implants.

MATERIALS AND METHODS

This IRB-approved, retrospective study identified patients who underwent SCS trials and implantation. Predictive modeling with nonparametric regression and margins plot analysis was used to determine the threshold for post-SCS trial pain scores associated with successful permanent SCS implant (defined as >50% pain relief). Nonparametric sensitivity and specificity analysis was performed. p < 0.05 was considered significant.

RESULTS

Eighty-eight patients with SCS trials were retrospectively identified (57.95% female, median age 52.5 ± 15.5 years). Of the total cohort, 79% had successful permanent SCS implantation. Post-SCS trial pain scores less than or equal to 4.9 had greater than 50% probability of a successful permanent SCS implant (97.14% sensitivity, 44.44% specificity, ROC = 0.71). Post-SCS trial pain scores between 4 and 7 were associated with a significantly higher probability of a successful SCS implant among patients without spine surgery compared with those with a history of spine surgery. Compared with males, females with pain scores between 5 and 7 had a higher probability of a successful SCS implant.

CONCLUSION

Low pain scores after SCS trial are predictive of successful SCS implants with high sensitivity. Males and surgical patients with higher pain scores had a lower probability of successful SCS implant than their counterparts. Larger studies are needed to further elucidate this relationship.

The Effectiveness of an Intensive Interdisciplinary Pain Rehabilitation Program in the Treatment of Post-Laminectomy Syndrome in Patients Who Have Failed Spinal Cord Stimulation

Introduction

Post-laminectomy syndrome (PLS) patients who have previously undergone spinal cord stimulation and failed to have significant improvement create a unique challenge for ongoing pain management. We hypothesize that, following successful completion of intensive, interdisciplinary pain rehabilitation (IPR), this patient population can achieve a significant reduction in pain, improvement in mood, functional levels, and self-efficacy.

Materials and methods

A retrospective chart review was conducted comparing the following for patients prior to enrollment in the IPR program and upon completion: numeric rating scale (NRS) pain scores; functional status via the six-minute walk test; mood via the Center for Epidemiologic Studies Depression Scale (CES-D), Multidimensional Pain Inventory (MPI) Life control scores and MPI Interference, and the Pain Catastrophizing Scale (PCS); and self-efficacy via the Pain Self-Efficacy Questionnaire (PSEQ).

Results

Forty-three patients met inclusion criteria, with 17 males and 26 females and a mean age of 64 years. Patients demonstrated a statistically significant increase in six-minute walk test distance of 104 m, a decrease in average NRS pain score of 1.4 points, an increase in average MPI life control by 8.3 points, a decrease average MPI interference by 5.3 points, an increase in average Short Form-36 by 6.5 points, an increase in average PCS by 4.4 points, and an increase in average PSEQ score of 18.1. Their average mood via CES-D improved by 4.2 points.

Conclusions

Intensive, interdisciplinary pain rehabilitation provides an effective therapeutic modality for patients with post-laminectomy syndrome who have failed spinal cord stimulation by decreasing pain levels and by increasing functional status and self-efficacy.

Spinal Cord Stimulation

Spinal cord stimulation (SCS) has been well established as a safe and effective treatment of pain derived from a wide variety of etiologies. Careful patient selection including a rigorous trial period and psychological evaluation are essential. When patients proceed to permanent implantation, various considerations should be made, such as the type of lead, type of anesthesia, and waveform patterns for SCS. This article discusses the common indications for SCS, patient selection criteria, and pertinent outcomes from randomized clinical trials related to common indications treated with SCS. Technical considerations, such as type of implant, anesthesia, and programming, are also discussed.

10‑Hydroxycamptothecin induces apoptosis in human fibroblasts by regulating miRNA‑23b‑3p expression

10-Hydroxycamptothecin (HCPT) effectively controls epidural fibrosis, but the exact underlying mechanisms remain ambiguous. Abnormal microRNA (miR)-23b-3p expression has been detected in various types of fibrotic tissues that are present in different diseases. The aim of the present study was to elucidate the mechanisms through which HCPT induces fibroblast apoptosis. Reverse transcription-quantitative polymerase chain reactions were performed on six traumatic scar samples and matched normal skin samples; traumatic scar formation was revealed to be significantly inversely associated with miR-23b-3p expression. In addition, the miR-23b-3p expression level in human fibroblasts was examined following HCPT treatment. The effects of HCPT and miR-23b-3p on fibroblast apoptosis were assessed using terminal deoxynucleotidyl-transferase-mediated dUTP nick-end labeling, flow cytometry and western blot analysis. The results demonstrated that HCPT treatment notably increased miR-23b-3p expression levels and accelerated fibroblast apoptosis. Therefore, upregulation of miR-23b-3p expression was demonstrated to promote fibroblast apoptosis, consistently with the effects of HCPT. The results of the present study indicated that HCPT may induce fibroblast apoptosis by regulating miR-23b-3p expression.

Application of a Novel Anti-Adhesive Membrane, E8002, in a Rat Laminectomy Model

Neuropathic pain after spinal surgery, so-called failed back surgery syndrome, is a frequently observed common complication. One cause of the pain is scar tissue formation, observed as post-surgical epidural adhesions. These adhesions may compress surrounding spinal nerves, resulting in pain, even after successful spinal surgery. E8002 is an anti-adhesive membrane. In Japan, a clinical trial of E8002 is currently ongoing in patients undergoing abdominal surgery. However, animal experiments have not been performed for E8002 in spinal surgery. We assessed the anti-adhesive effect of E8002 in a rat laminectomy model. The dura matter was covered with an E8002 membrane or left uncovered as a control. Neurological evaluations and histopathological findings were compared at six weeks postoperatively. Histopathological analyses were performed by hematoxylin–eosin and aldehyde fuchsin-Masson Goldner staining. Three assessment areas were selected at the middle and margins of the laminectomy sites, and the numbers of fibroblasts and inflammatory cells were counted. Blinded histopathological evaluation revealed that adhesions and scar formation were reduced in the E8002 group compared with the control group. The E8002 group had significantly lower numbers of fibroblasts and inflammatory cells than the control group. The present results indicate that E8002 can prevent epidural scar adhesions after laminectomy.

Burst or High-Frequency (10 kHz) Spinal Cord Stimulation in Failed Back Surgery Syndrome Patients With Predominant Back Pain: One Year Comparative Data

OBJECTIVES

Burst and 10 kHz spinal cord stimulation (SCS) demonstrated improvement for failed back surgery syndrome (FBSS) with predominant, refractory back pain. Here, we report the long-term follow-up of a previously published study comparing the safety and efficacy of burst vs. 10 kHz SCS for predominant back pain (70% of global pain) of FBSS patients.

METHODS

This comparative, observational study extended the follow-up period up to 20 months evaluating both SCS modalities. Pain intensity (visual analog scale [VAS_B , VAS_L ]), functional capacity (Pittsburgh Sleep Quality Index [PSQI]; depression (Beck Depression Inventory [BDI]), stimulation parameters and hardware and/or stimulation associated adverse events were recorded and analyzed over time.

RESULTS

Overall VAS_B (t_1,12  = 66.76, p < 0.001) and VAS_L (t_1,12  = 4.763, p < 0.049; p < 0.001) declined over time. Burst significantly decreased VAS_B by 87.5% (±17.7) (mean 8 ± 0.76 to 1 ± 1.41; t₁ =12.3, p < 0.001), and 10 kHz significant decreased VAS_B by 54.9% (±44) (mean 8 ± 0.63 to 3.5 ± 3.27; t₁ =3.09, p = 0.027). No significant differences for between SCS types were revealed (t₁ =1.75, p = 0.13). VAS_L was significantly suppressed for burst (burst: 3.6 ± 1.59 to 1.5 ± 1.06; t₁  = 3.32, p = 0.013). A significant effect of time was found for functional outcome with no significant differences between SCS types (PSQI: t_1,12  = 8.8, p = 0.012; and BDI: t₁  = 53.3, p < 0.001). No stimulation/hardware-related complications occurred.

DISCUSSION

Long-term data of this comparative study suggests that burst responsiveness was superior to 10 kHz in our small-scale cohort, thus a larger, randomized-controlled comparative study design is highly recommended.

Alternate Intraspinal Targets for Spinal Cord Stimulation: A Systematic Review

BACKGROUND

Conventional dorsal column spinal cord stimulation (SCS) provides less than optimal pain relief for certain pain syndromes and anatomic pain distributions. Practitioners have sought to treat these challenging therapeutic areas with stimulation of alternate intraspinal targets.

OBJECTIVE

To identify and systematically review the evidence for the value neuromodulating specific neuronal targets within the spinal canal to achieve relief of chronic pain.

METHODS

A systematic literature search was conducted using PubMed for clinical trials published from 1966 to March 1, 2015 to identify neurostimulation studies that employed non-dorsal column intraspinal stimulation to achieve pain relief. Identified studies on such targeted intraspinal stimulation were reviewed and graded using Evidence Based Interventional Pain Medicine criteria.

RESULTS

We found a total of 13 articles that satisfied our search criteria on targeted, non-dorsal column intraspinal stimulation for pain. We identified five studies on neurostimulation of the cervicomedullary junction, six studies on neurostimulation of the dorsal root ganglion, two studies on the neurostimulation of the conus medullaris, unfortunately none was found on intraspinal nerve root stimulation.

LIMITATIONS

The limitations of this review include the relative paucity of well-designed prospective studies on targeted SCS.

CONCLUSIONS

Clinical use of intraspinal neurostimulation is expanding at a very fast pace. Intraspinal stimulation of non-dorsal column targets may well be the future of neurostimulation as it provides new clinically significant neuromodulation of specific therapeutic targets that are not well or not easily addressed with conventional dorsal column SCS. In addition, they may avoid undesired stimulation induced paraesthesia, particularly in non-painful areas of the body.

Spinal cord stimulation attenuates temporal summation in patients with neuropathic pain

Evidence has shown that electrical stimulation at the dorsal columns attenuated the "wind-up" phenomenon in dorsal horn neurons in nerve-injured rats. This study was aimed to test the effect of spinal cord stimulation (SCS) on temporal summation (TS), the clinical correlate of the wind-up phenomenon in patients with radicular leg pain. Eighteen patients with SCS implants were tested both 30 minutes after SCS activation ("ON") and 2 hours after turning it off ("OFF"), in a random order. Temporal summation was evaluated in the most painful site in the affected leg and in the corresponding area in the contralateral leg by applying a tonic painful heat stimulus (46.5°C; 120 seconds) and simultaneous recording of the perceived heat pain intensity. Patients were also requested to report their clinical pain intensity (0-100 numerical pain scale) during SCS "ON" and "OFF". The Wilcoxon signed rank test was used in the comparisons between SCS "ON" and "OFF". Spinal cord stimulation activation significantly attenuated clinical pain intensity (from 66 ± 18 to 27 ± 31, P < 0.001). In the nonpainful leg, SCS activation failed to produce an effect on TS (24 ± 20 vs 21 ± 24 in SCS "OFF" and "ON", respectively; P = 0.277). In contrast, a significant decrease in the magnitude of TS in the affected leg was observed in response to SCS activation (from 32 ± 33 to 19 ± 24; P = 0.017). These results suggest that attenuation of TS, which likely represents suppression of hyperexcitability in spinal cord neurons, is a possible mechanism underlying SCS analgesia in patients with neuropathic pain.

Spinal cord stimulation: a review of the safety literature and proposal for perioperative evaluation and management

BACKGROUND CONTEXT

There is currently no consensus on appropriate perioperative management of patients with spinal cord stimulator implants. Magnetic resonance imaging (MRI) is considered safe under strict labeling conditions. Electrocautery is generally not recommended in these patients but sometimes used despite known risks.

PURPOSE

The aim was to discuss the perioperative evaluation and management of patients with spinal cord stimulator implants.

STUDY DESIGN

A literature review, summary of device labeling, and editorial were performed, regarding the safety of spinal cord stimulator devices in the perioperative setting.

METHODS

A literature review was performed, and the labeling of each Food and Drug Administration (FDA)-approved spinal cord stimulation system was reviewed. The literature review was performed using PubMed and the FDA website (www.fda.gov).

RESULTS

Magnetic resonance imaging safety recommendations vary between the models. Certain systems allow for MRI of the brain to be performed, and only one system allows for MRI of the body to be performed, both under strict labeling conditions. Before an MRI is performed, it is imperative to ascertain that the system is intact, without any lead breaks or low impedances, as these can result in heating of the spinal cord stimulation (SCS) and injury to the patient. Monopolar electrocautery is generally not recommended for patients with SCS; however, in some circumstances, it is used when deemed required by the surgeon. When cautery is necessary, bipolar electrocautery is recommended. Modern electrocautery units are to be used with caution as there remains a risk of thermal injury to the tissue in contact with the SCS. As with MRI, electrocautery usage in patients with SCS systems with suspected breaks or abnormal impedances is unsafe and may cause injury to the patient.

CONCLUSIONS

Spinal cord stimulation is increasingly used in patients with pain of spinal origin, particularly to manage postlaminectomy syndrome. Knowledge of the safety concerns of SCS and appropriate perioperative evaluation and management of the SCS system can reduce risks and improve surgical planning.

Cost-Effectiveness and Cost-Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study

Objective

To assess the cost‐effectiveness and cost‐utility of Spinal Cord Stimulation (SCS) in patients with failed back surgery syndrome (FBSS) refractory to conventional medical management (CMM).

Materials and Methods

We conducted an observational, multicenter, longitudinal ambispective study, where patients with predominant leg pain refractory to CMM expecting to receive SCS+CMM were recruited in 9 Italian centers and followed up to 24 months after SCS. We collected data on clinical status (pain intensity, disability), Health‐Related Quality‐of‐Life (HRQoL) and on direct and indirect costs before (pre‐SCS) and after (post‐SCS) the SCS intervention. Costs were quantified in € 2009, adopting the National Health Service's (NHS), patient and societal perspectives. Benefits and costs pre‐SCS versus post‐SCS were compared to estimate the incremental cost‐effectiveness and cost utility ratios.

Results

80 patients (40% male, mean age 58 years) were recruited. Between baseline and 24 months post‐SCS, clinical outcomes and HRQoL significantly improved. The EQ‐5D utility index increased from 0.421 to 0.630 (p < 0.0001). Statistically significant improvement was first observed six months post‐SCS. Societal costs increased from €6600 (pre‐SCS) to €13,200 (post‐SCS) per patient per year. Accordingly, the cost‐utility acceptability curve suggested that if decision makers' willingness to pay per Quality‐Adjusted‐Life‐Years (QALYs) was €60,000, SCS implantation would be cost‐effective in 80% and 85% of cases, according to the NHS's and societal point of views, respectively.

Conclusions

Our results suggest that in clinical practice, SCS+CMM treatment of FBSS patients refractory to CMM provides good value for money. Further research is encouraged in the form of larger, long‐term studies.

Failed back surgery syndrome: what's in a name? A proposal to replace "FBSS" by "POPS"…

BACKGROUND

The current definition of Failed Back Surgery Syndrome (FBSS) has a pejorative and restrictive connotation of blame and failure. Optimally, the evaluation of FBSS patients might be based on a multidimensional approach, involving an array of practitioners including spine surgeons, pain physicians, physiotherapists and behavioural specialists. Even though these clinical interactions should lead to a unique approach, one main problem comes from the fact that FBSS definition has varied over time and remains extremely controversial. There is now a need for global consensus about what we call FBSS, why, when and how. Discussing the name of this syndrome appears to be a logical starting point.

DISCUSSION

"PostOperative Persistent Syndrome", summarised by the acronym "POPS", could be an appropriate term to not only encapsulate failure but pain, function and psychosocial dysfunction following unsuccessful spine surgery whether from a technical or expectation standpoint. A return to the source might help to identify the real clinical problem, i.e. the pain mechanism: nociceptive, neuropathic pain or mixed. A clinical and radiological spine assessment is key to ensure that no further surgery is required, by distinguishing within the so-called FBSS population, "true" FBSS patients and "potential" FBSS patients, who are actually not FBSS patients, as an aetiological treatment of potential pain generators still remains possible.

CONCLUSION

We propose to replace the FBSS acronym by POPS. The ultimate goal of this redefinition would be to guide the patient towards the future rather than the past and to reach a consensus, based on network discussions, concerning the following items: integrate pain mechanisms into the diagnostic process; implement the notion of a predominant ratio between mechanical/neuropathic pain mechanisms, which defines the potential target for treatment options; create a network supported by a database, to prospectively pool and analyse data, using homogeneous evaluation tools and ultimately define outcome predictors in this population.

Mimicking the brain: evaluation of St Jude Medical's Prodigy Chronic Pain System with Burst Technology

The Prodigy is a new type of internal pulse generator that controls the delivery of electrical stimuli to nervous tissue. It is capable of delivering burst stimulation, which is a novel waveform that consists of closely spaced high-frequency electrical impulses delivered in packets riding on a plateau, and followed by a quiescent period. Its inception was based on mimicking burst firing in the nervous system and usually delivered by unmyelinated fibers that uniformly have a motivational affective homeostatic function. It thereby targets a multimodal salience network, even though the stimuli are delivered at the level of the spinal cord. As such, it is specifically capable of influencing the affective/attentional components of pain. Burst stimulation was initially safely applied off-label to the auditory cortex for tinnitus, and later also to the spinal cord, the somatosensory cortex for neuropathic pain, subcutaneously for failed back surgery syndrome, and cingulate cortex for addiction and tinnitus.

Utilization of spinal cord stimulation in patients with failed back surgery syndrome

STUDY DESIGN

Retrospective analysis of a population-based insurance claims data set.

OBJECTIVE

To evaluate the use of spinal cord stimulation (SCS) and lumbar reoperation for the treatment of failed back surgery syndrome (FBSS), and examine their associated complications and health care costs.

SUMMARY OF BACKGROUND DATA

FBSS is a major source of chronic neuropathic pain and affects up to 40% of patients who undergo lumbosacral spine surgery for back pain. Thus far, few economic analyses have been performed comparing the various treatments for FBSS, with these studies involving small sample sizes. In addition, the nationwide practices in the use of SCS for FBSS are unknown.

METHODS

The MarketScan data set was used to analyze patients with FBSS who underwent SCS or spinal reoperation between 2000 and 2009. Propensity score methods were used to match patients who underwent SCS with those who underwent lumbar reoperation to examine health care resource utilization. Postoperative complications were analyzed with multivariate logistic regression. Health care use was analyzed using negative binomial and general linear models.

RESULTS

The study cohort included 16,455 patients with FBSS, with 395 undergoing SCS implantation (2.4%). Complication rates at 90 days were significantly lower for SCS than spinal reoperation (P < 0.0001). Also in the matched cohort, hospital stay (P < 0.0001) and associated charges (P = 0.016) were lower for patients with SCS. However outpatient, emergency room, and medication charges were similar between the 2 groups. Overall cost totaling $82,586 at 2 years was slightly higher in the lumbar reoperation group than in the SCS group with total cost of $80,669 (P = 0.88).

CONCLUSION

Although previous studies have demonstrated superior efficacy for the treatment of FBSS, SCS remains underused. Despite no significant decreases in overall health care cost with SCS implantation, because it is associated with decreased complications and improved outcomes, this technology warrants closer consideration for the management of chronic pain in patients with FBSS.

Clinical experiences of performing transforaminal balloon adhesiolysis in patients with failed back surgery syndrome: two cases report

Epidural fibrosis is a contributing factor to the persistent pain that is associated with failed back surgery syndrome (FBSS) and other pathophysiologies, particularly as it inhibits the passage of regional medications to areas responsible for pain. Therefore, effective mechanical detachment of epidural fibrosis can contribute to pain reduction and improve function in FBSS patients. In this report, we describe the successful treatment of FBSS patients with epidural adhesiolysis using a Fogarty catheter via the transforaminal approach.

High sensitive C-reactive protein-Effective tool in determining postoperative recovery in lumbar disc disease

BACKGROUND

It is common in medical practice to see patients having persistent pain and radiculopathy even after undergoing discectomy surgery. Inflammatory cytokines, such as interleukins are produced at the site of disc herniation and are now considered responsible for the pain perceived by the patient. This study has used high sensitive C-reactive protein (HSCRP) assay for predicting inflammation around the nerve roots on very same principle, which has used HSCRP for predicting coronary artery diseases in current clinical practice. Thus, purpose of this study is to test whether HSCRP can stand as an objective tool to predict postoperative recovery in patients undergoing lumbar discectomy. That is, to study association between preoperative HSCRP blood level and postoperative recovery with the help of modified Oswestry Back Disability Score.

MATERIALS AND METHODS

A study group consisting of 50 cases of established lumbar disc disease and control group of 50 normal subjects, matched with the study group. Both the study and control groups were subjected to detailed evaluation with the help of modified Oswestry Low Back Pain Scale both pre and postoperatively at 3 months, 6 months and 1-year. The preoperative blood samples were analyzed to assess the HSCRP concentration. All the cases underwent surgery over a period of 1-year by the same surgeon.

RESULTS

The level of HSCRP in the study group was between 0.050- and 0.710 mg/dL and in the control group, 0.005-0.020 mg/dL. There was highly significant positive correlation between preoperative HSCRP level and postoperative score at P < 0.005. Cases with HSCRP level in the range of 0.1820 ± 0.079 mg/dL, showed better recovery (score improved > 10 points), while those with HSCRP level in the range of 0.470 ± 0.163 mg/dL, showed poor recovery (score improved < 10 points).

CONCLUSION

HSCRP will serve as a good supplementary prognostic marker for operative decision making in borderline and troublesome cases of lumbar disc disease.