Therapeutic trial of fluoroscopic interlaminar epidural steroid injection for axial low back pain: effectiveness and outcome predictors

Predictors of successful treatment after transforaminal epidural steroid injections in patients with lumbar disc herniation

BACKGROUND

Epidural steroid injections are common procedures used to treat lumbosacral radicular pain due to lumbar disc herniation (LDH). It is crucial for the clinician to anticipate which patients can benefit from interventional treatment options.

OBJECTIVE

This study aimed to examine the effect of radiological and clinical parameters on lumbar transforaminal epidural steroid injections (TFESI)/local anesthetic injection outcomes in patients with LDH.

METHODS

This study included 286 patients with LDH (146 males and 140 females). All patients received a fluoroscopically guided TFESI (triamcinolone acetonide 40 mg, lidocaine 2%, and 2.5 ml of physiological saline). Patients were evaluated according to radicular pain, the Oswestry Disability Index (ODI) and the Hospital Anxiety and Depression Scale at baseline and 3 months after the injections. Demographic, clinical and magnetic resonance imaging (MRI) findings were recorded to assess the predictive factors for TFESI outcomes. Pfirrmann Grades 1 and 2 were classified as low-grade nerve root compression and Grade 3 was classified as highgrade nerve root compression.

RESULTS

Compared to baseline measurements there were significant improvements in radicular pain, ODI score, Laseque angle, and Schober test scores 3 months after injection. Improvements of at least 50% in radicular pain relief and the ODI functionality index were (n= 214) 82%, (n= 182) 70% respectively at 3 months. Correlation analyses revealed that a shorter duration of symptoms, lowgrade nerve root compression and foraminal/extraforaminal location on MRI findings were associated with a favorable response.

CONCLUSIONS

Lowgrade nerve root compression was a predictor of a favorable response to TFESI.

Interlaminar versus transforaminal epidural steroid injections: a review of efficacy and safety

Spine intervention is an important treatment option for the management of spinal pain, and the numbers of the most representative epidural steroid injection (ESI) procedures performed are expected to increase significantly in the future along with increased life expectancy and the increasing prevalence of spinal disorders. Therefore, it is important to understand the efficacy of ESIs according to each spinal disorder they are administered to treat, and one must be familiar with the possible complications. In fact, although numerous ESI-related articles have been published, there is still considerable controversy regarding the efficacy of ESI procedures. Furthermore, due to the rarity of serious complications, most instances have been recorded in the form of case reports. In this article, we aimed to review the indications of cervical and lumbar ESIs and to compare interlaminar ESI (ILESI) and transforaminal ESI (TFESI) techniques in terms of analgesic efficacy, possible complications, and safety profiles. This article includes opinions based on the authors' experience with ESI indications and efficacy, and presents practical tips for coping with specific situations related to each complication. By combining the dedicated anatomical understanding of radiologists with image-guided interventions, ESI is expected to stand out in the rapidly expanding field of spine intervention.

Clinical practice guidelines on interventional management of low back pain: A synthesis of recommendations

OBJECTIVE

To summarize the recommendations on the interventional management of subacute and chronic nonradicular low back pain (LBP) from the 21 quality-appraised clinical practice guidelines (CPGs) identified in a previously published paper: "Quality of Clinical Practice Guidelines on Interventional Management of Low Back Pain: A Systematic Review." By disseminating this information, we aimed to facilitate the implementation of these recommendations into clinical practice. TYPE: Systematic Review LITERATURE SURVEY: Electronic bibliographic databases, guideline databases, and gray literature were searched from January 2016 to January 2020 to identify CPGs that met study criteria.

METHODOLOGY

A total of 21 CPGs were quality appraised and interventional management recommendations were extracted and organized into several treatment categories including epidural steroid injections, radiofrequency procedures (RF), facet injections, sacroiliac injections, and prolotherapy. Within each treatment category, the recommendations were organized based on two factors: quality of CPG and strength of recommendation.

SYNTHESIS

Overall, there was no consistency in recommendations for or against any interventional procedure, even when accounting for the quality of the CPG. In all of the CPGs reviewed, the most common strength of recommendation was weakly for. The second, third, and fourth most common strength of recommendations were inconclusive, weakly against, and strongly against, respectively, and the least common was strongly for. The treatment categories with the greatest number of recommendations were RF procedures (most common strength of recommendation was weakly for) and facet procedures. Among the high-quality CPGs, the most common strength of recommendation was inconclusive.

CONCLUSIONS

Most of the interventional management recommendations for management of nonradicular LBP in the 21 CPGs appraised in this review were either weakly for, weakly against, or inconclusive, with several recommendations within each treatment category contradicting each other. Appraisal of Guidelines for Research & Evaluation Instrument quality appraisals of CPGs on interventional management of LBP were of unclear utility in guiding clinical implementation.

Health-Care Utilization and Outcomes with 10 kHz Spinal Cord Stimulation for Chronic Refractory Pain

Background

Chronic pain is a common condition associated with decreased quality of life and increased health-care costs. Opioid analgesics are routinely used to treat chronic pain despite limited evidence of long-term efficacy. Spinal cord stimulation at a frequency of 10 kilohertz (10kHz-SCS) has been shown to be effective for treating chronic pain.

Objective

This study was conducted to evaluate the effects of 10kHz-SCS on patients’ pain intensity, volume of pain interventions, and opioid intake in a real-world setting.

Study Design

This study was a retrospective review of patient data.

Setting

The study was conducted at a single, community-based clinic.

Methods

Outcomes including pain relief, quality of life, opioid intake, and rate of health-care usage were evaluated using data from patients who were implanted with a 10kHz-SCS device to treat chronic pain. These outcomes were then compared for the pre- and post-implant periods.

Results

A total of 47 patients with a mean follow-up duration of 15.6 ± 6.2 months were included in this analysis. Mean pain relief was 73 ± 22% and 89% were responders at the final follow-up visit. The rate of medical interventions fell from 3.48±3.05 per year before starting 10kHz-SCS to 0.49±1.16 per year afterward (P < 0.001). Of 30 patients with available opioid consumption data, 89% maintained or decreased their intake after implant.

Conclusion

Retrospective data from a single center, with minimal exclusion criteria shows clinically significant pain relief with 10kHz-SCS, accompanied by significant indirect benefits including stable or reduced opioid use and reduced interventional procedures.

Evaluation of transforaminal epidural steroid injections for discogenic axial lumbosacral back pain utilizing PROMIS as an outcome measure

BACKGROUND CONTEXT

Discogenic lumbosacral back pain continues to present a challenging clinical entity with limited, controversial therapeutic options. No study to date has evaluated the efficacy of fluoroscopically guided transforaminal epidural steroid injections (TFESI) in a homogenous patient population with axial lumbosacral back pain from discogenic pathology utilizing strict, explicitly clinical and radiographic criteria. Additionally, there is a paucity of published data utilizing Patient Reported Outcome Measurement Information System (PROMIS) scores as an outcome measure for interventional spine procedures.

PURPOSE

Evaluate the therapeutic effect of TFESIs in a specific subset of patients with discogenic axial lumbosacral back pain. Investigate PROMIS as an outcome measure for interventional spine procedures targeting focal degenerative spinal pathology.

STUDY DESIGN/SETTING

Retrospective review of patients presenting to a multidisciplinary, tertiary academic spine center.

PATIENT SAMPLE

Three thousand eight hundred eighty-one patients were screened for inclusion. A total of 26 patients with discogenic axial low back, based on strict clinical and radiographic criteria, underwent TFESIs. All patients had axial low back pain without radicular pain, ≥3 clinical features of discogenic pain, corroborative radiographic features of active discogenic pathology on lumbar spine magnetic resonance imaging without confounding spinal pathology.

OUTCOME MEASURES

PROMIS Pain Interference (PI) v1.1, PROMIS Physical Function (PF) v1.2/v2.0, and PROMIS Depression (D) v1.0 outcome scores were collected at baseline and postprocedure follow-up.

METHODS

Query of an institutional, patient reported outcome database and subsequent retrospective review of electronic medical records was performed. Statistical analysis comparing baseline and postprocedural PROMIS outcome scores and correlation between these instruments was performed. Additionally, an exploratory investigation of minimal clinically important difference achievement rates was performed.

RESULTS

Analysis determined a statistically significant improvement in PROMIS PI (p=.017, 95% CI=-8.02 to -1.82) and PROMIS PF (p=.003, 95% CI=0.91-8.72) scores after treatment with TFESIs. At post treatment time points, TFESI had medium effect size on pain (d=0.55) and function (d=0.59). Change in PROMIS D scores (p=.488, 95% CI -1.74-3.54; d=.08) did not demonstrate statistical significance. Pearson correlation demonstrated a moderate negative correlation (r=-0.544, p=.004) between PROMIS PF with PROMIS PI. Correlation between PROMIS PF (r=-0.239, p=.24) and PROMIS PI (r=0.198, p=.33) with PROMIS D was not significant. Fourteen (53.8%) and 9 (34.6%) subjects achieved minimum clinically important difference (MCID) for PROMIS PI and PROMIS PF, respectively. Nine subjects (34.6%) achieved MCID for PROMIS D despite not otherwise reaching statistical significance otherwise.

CONCLUSIONS

Utilizing PROMIS as an outcome measure, discogenic axial lumbosacral back pain patients appear to benefit from TFESI in terms of pain and physical function. This study contributes to the growing body of literature utilizing PROMIS scores in patients with clinical sequelae of degenerative spinal pathology; however, prospective studies are needed.

Association of Protein and Genetic Biomarkers With Response to Lumbar Epidural Steroid Injections in Subjects With Axial Low Back Pain

OBJECTIVE

The purpose of this observational study was to examine the association of protein and genetic biomarkers with pain and pain-related disability in individuals with axial low back pain undergoing epidural steroid injections.

DESIGN

Forty-eight adults with axial low back pain undergoing an epidural steroid injection were recruited from an academic medical center. Blood samples were assayed at baseline and follow-up for plasma proteins and functional single-nucleotide polymorphisms associated with pain. Data regarding pain and function were collected at baseline and follow-up. The characteristics of responders (defined as 50% improvement in pain score) and nonresponders were compared, and the association between response and baseline biomarkers was examined.

RESULTS

Thirty-five percent of subjects were responders to injection. Responders had lower baseline plasma levels of chondroitin sulfate 846 and higher neuropeptide Y and serotonin levels than nonresponders, and baseline neuropeptide Y level correlated with change in disability levels. In addition, subjects with the variant allele for the catechol-O-methyltransferase single-nucleotide polymorphism demonstrated increased odds of responding to the injection.

CONCLUSIONS

These data identify candidates who may have utility for patient selection for spinal procedures and provide support for exploration in prospective studies to assess and validate their predictive ability.

Guideline summary review: an evidence-based clinical guideline for the diagnosis and treatment of low back pain

BACKGROUND CONTEXT

The North American Spine Society's (NASS) Evidence Based Clinical Guideline for the Diagnosis and Treatment of Low Back Pain features evidence-based recommendations for diagnosing and treating adult patients with nonspecific low back pain. The guideline is intended to reflect contemporary treatment concepts for nonspecific low back pain as reflected in the highest quality clinical literature available on this subject as of February 2016.

PURPOSE

The purpose of the guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for adult patients with nonspecific low back pain. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition.

STUDY DESIGN

This is a guideline summary review.

METHODS

This guideline is the product of the Low Back Pain Work Group of NASS' Evidence-Based Clinical Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questions to address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members utilized NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guideline was submitted to an internal and external peer review process and ultimately approved by the NASS Board of Directors.

RESULTS

Eighty-two clinical questions were addressed, and the answers are summarized in this article. The respective recommendations were graded according to the levels of evidence of the supporting literature.

CONCLUSIONS

The evidence-based clinical guideline has been created using techniques of evidence-based medicine and best available evidence to aid practitioners in the diagnosis and treatment of adult patients with nonspecific low back pain. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flowchart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx.

Stem cell injections for axial back pain: a systematic review of associated risks and complications with a case illustration of diffuse hyperplastic gliosis resulting in cauda equina syndrome

OBJECTIVE

Axial low-back pain is a disease of epidemic proportions that exerts a heavy global toll on the active workforce and results in more than half a trillion dollars in annual costs. Stem cell injections are being increasingly advertised as a restorative solution for various degenerative diseases and are becoming more affordable and attainable by the public. There have been multiple reports in the media of these injections being easily available abroad outside of clinical trials, but scientific evidence supporting them remains scarce. The authors present a case of a serious complication after a stem cell injection for back pain and provide a systematic review of the literature of the efficacy of this treatment as well as the associated risks and complications.

METHODS

A systematic review of the literature was performed using the PubMed, Google Scholar, and Scopus online electronic databases to identify articles reporting stem cell injections for axial back pain in accordance with the PRISMA guidelines. The primary focus was on outcomes and complications. A case of glial hyperplasia of the roots of the cauda equina directly related to stem cell injections performed abroad is also reported.

RESULTS

The authors identified 14 publications (including a total of 147 patients) that met the search criteria. Three of the articles presented data for the same patient population with different durations of follow-up and were thus analyzed as a single study, reducing the total number of studies to 12. In these 12 studies, follow-up periods ranged from 6 months to 6 years, with 50% having a follow-up period of 1 year or less. Most studies reported favorable outcomes, although 36% used subjective measures. There was a tendency for pain relief to wane after 6 months to 2 years, with patients seeking a surgical solution. Only 1 study was a randomized controlled trial (RCT).

CONCLUSIONS

There are still insufficient data to support stem cell injections for back pain. Additional RCTs with long-term follow-up are necessary before statements can be made regarding the efficacy and safety.

Bony stress in the lumbar spine is associated with intervertebral disc degeneration and low back pain: a retrospective case-control MRI study of patients under 25 years of age

PURPOSE

Abnormal stress in the lumbar vertebra, also known as bony stress, can be a precursor to degenerative changes which may manifest as low back pain (LBP). However, the prevalence of bony stress in the lumbar spine and its relationship with degenerative changes and LBP is unclear. The purpose of this study was to evaluate the prevalence of bony stress in the lumbar spine and its relationship with intervertebral disc (IVD) degeneration, facet osteoarthritis and LBP in patients under 25 years of age.

METHODS

A retrospective case-control study of 130 patients under 25 years of age was conducted from a population of 493 patients who had lumbar MRI across three imaging centres over three years. A cohort of 55 consecutive patients with bony stress was identified. A control group of consecutive patients (n = 75) without bony stress was also selected from the population.

RESULTS

Bony stress was prevalent in 11% (95% CI [8.4-14.5%]) of patients and was not diagnosed in 36% (95% CI [22-55%]) of these cases. Patients with bony stress had over twofold (OR 2.3, 95% CI [1.1-4.8]) and fivefold (OR 5.3, 95% CI [2.11-13.3]) higher likelihood of having IVD degeneration and LBP, respectively, when compared with the control group. Bony stress was not found to be associated with facet osteoarthritis.

CONCLUSION

Bony stress in the lumbar spine was prevalent in 11% of patients under 25 years of age. It was commonly undiagnosed in radiology reports (not reported in 36% of the cases). Being significantly associated and with an increased likelihood of IVD degeneration and LBP, we posit that bony stress is likely a symptomatic and clinically meaningful diagnostic entity in the assessment of LBP. These slides can be retrieved under Electronic Supplementary Material.

Fluoroscopically Guided Epidural Injections of the Cervical and Lumbar Spine

Advances in imaging and the development of injection techniques have enabled spinal intervention to become an important tool in managing chronic spinal pain. Epidural steroid injection (ESI) is one of the most widely used spinal interventions; it directly delivers drugs into the epidural space to relieve pain originating from degenerative spine disorders-central canal stenoses and neural foraminal stenoses-or disk herniations. Knowledge of the normal anatomy of the epidural space is essential to perform an effective and safe ESI and to recognize possible complications. Although computed tomographic (CT) or combined CT-fluoroscopic guidance has been increasingly used in ESI, conventional fluoroscopic guidance is generally performed. In ESI, drugs are delivered into the epidural space by interlaminar or transforaminal routes in the cervical spine or by interlaminar, transforaminal, or caudal routes in the lumbar spine. Epidurography is usually performed before drug delivery to verify the proper position of the needle in the epidural space. A small amount of contrast agent is injected with fluoroscopic guidance. Familiarity with the findings on a typical "true" epidurogram (demonstrating correct needle placement in the epidural space) permits proper performance of ESI. Findings on "false" epidurograms (demonstrating incorrect needle placement) include muscular staining and evidence of intravascular injection, inadvertent facet joint injection, dural puncture, subdural injection, and intraneural or intradiscal injection. ^©RSNA, 2016 An earlier incorrect version of this article appeared online. This article was corrected on December 22, 2016.

Paravertebral spinal injection for the treatment of patients with degenerative facet osteoarthropathy: Evidence of motor performance improvements based on objective assessments

BACKGROUND

This study examined short- and long-term improvements in motor performance, quantified using wearable sensors, in response to facet spine injection in degenerative facet osteoarthropathy patients.

METHODS

Adults with confirmed degenerative facet osteoarthropathy were recruited and were treated with medial or intermediate branch block injection. Self-report pain, health condition, and disability (Oswestry), as well as objective motor performance measures (gait, balance, and timed-up-and-go) were obtained in five sessions: pre-surgery (baseline), immediately after the injection, one-month, three-month, and 12-month follow-ups. Baseline motor performance parameters were compared with 10 healthy controls.

FINDINGS

Thirty patients (age=50 (14) years) and 10 controls (age=46 (15) years) were recruited. All motor performance parameters were significantly different between groups. Results showed that average pain and Oswestry scores improved by 51% and 24%, respectively among patients, only one month after injection. Similarly, improvement in motor performance was most noticeable in one-month post-injection measurements; most improvements were observed in gait speed (14% normal walking, P<0.02), hip sway within balance tests (63% eyes-open P<0.01), and turning velocity within the timed-up-and-go test (28%, P<0.02). Better baseline motor performance led to better outcomes in terms of pain relief; baseline turning velocity was 18% faster among the responsive compared to the non-responsive patients.

INTERPRETATIONS

Spinal injection can temporarily (one to three months) improve motor performance in degenerative facet osteoarthropathy patients. Successful pain relief in response to treatment is independent of demographic characteristics and initial pain but dependent on baseline motor performance. Immediate self-reported pain relief is unrelated to magnitude of gradual improvement in motor performance.

The effect of journal impact factor, reporting conflicts, and reporting funding sources, on standardized effect sizes in back pain trials: a systematic review and meta-regression

BACKGROUND

Low back pain is a common and costly health complaint for which there are several moderately effective treatments. In some fields there is evidence that funder and financial conflicts are associated with trial outcomes. It is not clear whether effect sizes in back pain trials relate to journal impact factor, reporting conflicts of interest, or reporting funding.

METHODS

We performed a systematic review of English-language papers reporting randomised controlled trials of treatments for non-specific low back pain, published between 2006-2012. We modelled the relationship using 5-year journal impact factor, and categories of reported of conflicts of interest, and categories of reported funding (reported none and reported some, compared to not reporting these) using meta-regression, adjusting for sample size, and publication year. We also considered whether impact factor could be predicted by the direction of outcome, or trial sample size.

RESULTS

We could abstract data to calculate effect size in 99 of 146 trials that met our inclusion criteria. Effect size is not associated with impact factor, reporting of funding source, or reporting of conflicts of interest. However, explicitly reporting 'no trial funding' is strongly associated with larger absolute values of effect size (adjusted β=1.02 (95 % CI 0.44 to 1.59), P=0.001). Impact factor increases by 0.008 (0.004 to 0.012) per unit increase in trial sample size (P<0.001), but does not differ by reported direction of the LBP trial outcome (P=0.270).

CONCLUSIONS

The absence of associations between effect size and impact factor, reporting sources of funding, and conflicts of interest reflects positively on research and publisher conduct in the field. Strong evidence of a large association between absolute magnitude of effect size and explicit reporting of 'no funding' suggests authors of unfunded trials are likely to report larger effect sizes, notwithstanding direction. This could relate in part to quality, resources, and/or how pragmatic a trial is.

Lateral parasagittal versus midline interlaminar lumbar epidural steroid injection for management of low back pain with lumbosacral radicular pain: a double-blind, randomized study

BACKGROUND

Epidural steroid injections are commonly used for management of low back pain with lumbosacral radicular pain and can be administered by either interlaminar or transforaminal routes. The transforaminal route is reported to be more effective than the interlaminar route due to higher delivery of drug at the ventral epidural space. However, the transforaminal route has been associated with serious complications including spinal cord injury and permanent paralysis. Hence, there is a search for a technically better route with fewer complications for drug delivery into the ventral epidural space. Recently, a parasagittal interlaminar (PIL) approach of epidural contrast injection was reported to have 100% ventral epidural spread. However, the therapeutic efficacy of this route has never been investigated. We compared the therapeutic efficacy of the PIL approach and midline interlaminar (MIL) approach. We hypothesized that the PIL approach may produce a better clinical outcome because of better ventral epidural spread of the drug compared with MIL approach.

METHODS

Thirty-seven patients were randomized to receive injection of 80 mg methylprednisolone either by the PIL (PIL group, n = 19) or MIL (MIL group, n = 18) approach under fluoroscopic guidance. Patients were evaluated for effective pain relief (≥50% from baseline) by visual analog scale and improvement in disability by the modified Oswestry Disability Questionnaire at intervals of 15 days, 1, 2, 3, and 6 months. Patients having <50% pain relief from baseline received additional epidural injection of the same drug, dosage, and route, a maximum of 3 injections at least 15 days apart. The primary outcome of our study was the incidence of effective pain relief at 6 months.

RESULTS

The incidence of patients having effective pain relief was higher with the PIL approach (13/19 [68.4%]) vs MIL (3/18 [16.7%]) at the end of 6 months. A significantly higher relative success of effective pain relief was noted in the PIL group (relative risk, 4.10; 95% confidence interval, 1.40-12.05; P = 0.001) at the end of the 6-month follow up with the requirement of fewer total injections (29 vs 41 in MIL, P = 0.043). Visual analog scale and modified Oswestry Disability Questionnaire scores were significantly lower in the PIL group compared with the MIL group at all time intervals after the procedure. Ventral epidural spread of contrast was significantly higher in the PIL 89.7% vs 31.7% in the MIL group. The administration of epidural steroid injection was without any complications with an exact 95% Clopper-Pearson confidence interval of 0.0% to 17.6% in the PIL group and 0.0% to 18.5% in the MIL group.

CONCLUSIONS

Epidural steroid injection administered with the PIL approach was significantly more effective for pain relief and improvement in disability than the MIL approach for 6 months in the management of low back pain with lumbosacral radicular pain.