The Effectiveness of Lumbar Transforaminal Injection of Steroids: A Comprehensive Review with Systematic Analysis of the Published Data

Key safety considerations when administering epidural steroid injections

Neurological and other complications of epidural steroid injections have been widely discussed in recent years. Consequently, the US FDA issued a warning about serious neurological events, some resulting in death, and consequently is requiring label changes. Neurological adverse events numbering 131, including 41 cases of arachnoiditis, have been identified by the FDA, and 700 cases of fungal meningitis following injection of contaminated steroids. A review of the literature reveals an overwhelming proportion of the complications are related to transforaminal epidural injections, with the majority of them to cervical transforaminal epidural injections. This perspective describes the prevalence of administering epidural injections, complications, pathoanatomy, mechanism of injury and various preventive strategies.

Do Epidural Injections Provide Short- and Long-term Relief for Lumbar Disc Herniation? A Systematic Review

BACKGROUND

As part of a comprehensive nonsurgical approach, epidural injections often are used in the management of lumbar disc herniation. Recent guidelines and systematic reviews have reached different conclusions about the efficacy of epidural injections in managing lumbar disc herniation.

QUESTIONS/PURPOSES

In this systematic review, we determined the efficacy (pain relief and functional improvement) of the three anatomic approaches (caudal, lumbar interlaminar, and transforaminal) for epidural injections in the treatment of disc herniation.

METHODS

We performed a literature search from 1966 to June 2013 in PubMed, Cochrane library, US National Guideline Clearinghouse, previous systematic reviews, and cross-references for trials studying all types of epidural injections in managing chronic or chronic and subacute lumbar disc herniation. We wanted only randomized controlled trials (RCTs) (either placebo or active controlled) to be included in our analysis, and 66 studies found in our search fulfilled these criteria. We then assessed the methodologic quality of these 66 studies using the Cochrane review criteria for RCTs. Thirty-nine studies were excluded, leaving 23 RCTs of high and moderate methodologic quality for analysis. Evidence for the efficacy of all three approaches for epidural injection under fluoroscopy was strong for short-term (< 6 months) and moderate for long-term (≥ 6 months) based on the Cochrane rating system with five levels of evidence (best evidence synthesis), with strong evidence denoting consistent findings among multiple high-quality RCTs and moderate evidence denoting consistent findings among multiple low-quality RCTs or one high-quality RCT. The primary outcome measure was pain relief, defined as at least 50% improvement in pain or 3-point improvement in pain scores in at least 50% of the patients. The secondary outcome measure was functional improvement, defined as 50% reduction in disability or 30% reduction in the disability scores.

RESULTS

Based on strong evidence for short-term efficacy from multiple high-quality trials and moderate evidence for long-term efficacy from at least one high quality trial, we found that fluoroscopic caudal, lumbar interlaminar, and transforaminal epidural injections were efficacious at managing lumbar disc herniation in terms of pain relief and functional improvement.

CONCLUSIONS

The available evidence suggests that epidural injections performed under fluoroscopy by trained physicians offer improvement in pain and function in well-selected patients with lumbar disc herniation.

Correlation of the Patient Reported Outcomes Measurement Information System with legacy outcomes measures in assessment of response to lumbar transforaminal epidural steroid injections

BACKGROUND AND PURPOSE

The Patient Reported Outcomes Measurement Information System is a newly developed outcomes measure promulgated by the National Institutes of Health. This study compares changes in pain and physical function-related measures of this system with changes on the Numeric Rating Pain Scale, Roland Morris Disability Index, and the European Quality of Life scale 5D questionnaire in patients undergoing transformational epidural steroid injections for radicular pain.

MATERIALS AND METHODS

One hundred ninety-nine patients undergoing transforaminal epidural steroid injections for radicular pain were enrolled in the study. Before the procedure, they rated the intensity of their pain by using the 0-10 Numeric Rating Pain Scale, Roland Morris Disability Index, and European Quality of Life scale 5D questionnaire. Patients completed the Patient Reported Outcomes Measurement Information System Physical Function, Pain Behavior, and Pain Interference short forms before transforaminal epidural steroid injections and at 3 and 6 months. Seventy and 43 subjects replied at 3- and 6-month follow-up. Spearman rank correlations were used to assess the correlation between the instruments. The minimally important differences were calculated for each measurement tool as an indicator of meaningful change.

RESULTS

All instruments were responsive in detecting changes at 3- and 6-month follow-up (P < .0001). There was significant correlation between changes in Patient Reported Outcomes Measurement Information System scores and legacy questionnaires from baseline to 3 months (P < .05). There were, however, no significant correlations in changes from 3 to 6 months with any of the instruments.

CONCLUSIONS

The studied Patient Reported Outcomes Measurement Information System domains offered responsive and correlative psychometric properties compared with legacy instruments in a population of patients undergoing transforaminal epidural steroid injections for radicular pain.

Epidural injections in prevention of surgery for spinal pain: systematic review and meta-analysis of randomized controlled trials

BACKGROUND CONTEXT

Low back pain is debilitating and costly, especially for patients not responding to conservative therapy and requiring surgery.

PURPOSE

Our objective was to determine whether epidural steroid injections (ESI) have a surgery-sparing effect in patients with spinal pain.

STUDY DESIGN/SETTING

The study design was based on a systematic review and meta-analysis.

METHODS

Databases searched included Cochrane, PubMed, and EMBASE. The primary analysis evaluated randomized controlled trials (RCTs) in which treatment groups received ESI and control groups underwent control injections. Secondary analyses involved RCTs comparing surgery with ESI, and subgroup analyses of trials comparing surgery with conservative treatment in which the operative disposition of subjects who received ESI were evaluated.

RESULTS

Of the 26 total studies included, only those evaluating the effect of ESI on the need for surgery as a primary outcome examined the same patient cohort, providing moderate evidence that patients who received ESI were less likely to undergo surgery than those who received control treatment. For studies examining surgery as a secondary outcome, ESI demonstrated a trend to reduce the need for surgery for short-term (<1 year) outcomes (risk ratio, 0.68; 95% confidence interval, 0.41-1.13; p=.14) but not long-term (≥1 year) outcomes (0.95, 0.77-1.19, p=.68). Secondary analyses provided low-level evidence suggesting that between one-third and half of patients considering surgery who undergo ESI can avoid surgery.

CONCLUSIONS

Epidural steroid injections may provide a small surgery-sparing effect in the short term compared with control injections and reduce the need for surgery in some patients who would otherwise proceed to surgery.

Epidural Steroid Injections are Safe and Effective: Multisociety Letter in Support of the Safety and Effectiveness of Epidural Steroid Injections

BACKGROUND

In April 2014, the Food and Drug Administration (FDA) issued a Drug Safety Communication requesting that corticosteroid labeling include warnings that injection of corticosteroids into the epidural space of the spine may result in rare but serious adverse events, including loss of vision, stroke, paralysis, and death.

RESULTS

The International Spine Intervention Society spearheaded a collaboration of more than a dozen other medical societies in submitting the letter below to the FDA on November 7, 2014. We are publishing the letter to ensure that the readership of Pain Medicine is aware of the multisociety support for the safety and effectiveness of these procedures. A special note of thanks to all of the societies who signed on in support of the message.

Epidural steroid injections for radicular lumbosacral pain: a systematic review

Most clinical guidelines do not recommend routine use of epidural steroid injections for the management of chronic low back pain. However, many clinicians do not adhere to these guidelines. This comprehensive evidence overview concluded that off-label epidural steroid injections provide small short-term but not long- term leg-pain relief and improvement in function; injection of steroids is no more effective than injection of local anesthetics alone; post-procedural complications are uncommon, but the risk of contamination and serious infections is very high. The evidence does not support routine use of off-label epidural steroid injections in adults with benign radicular lumbosacral pain.

Epidural steroid injections, conservative treatment, or combination treatment for cervical radicular pain: a multicenter, randomized, comparative-effectiveness study

BACKGROUND

Cervical radicular pain is a major cause of disability. No studies have been published comparing different types of nonsurgical therapy.

METHODS

A comparative-effectiveness study was performed in 169 patients with cervical radicular pain less than 4 yr in duration. Participants received nortriptyline and/or gabapentin plus physical therapies, up to three cervical epidural steroid injections (ESI) or combination treatment over 6 months. The primary outcome measure was average arm pain on a 0 to 10 scale at 1 month.

RESULTS

One-month arm pain scores were 3.5 (95% CI, 2.8 to 4.2) in the combination group, 4.2 (CI, 2.8 to 4.2) in ESI patients, and 4.3 (CI, 2.8 to 4.2) in individuals treated conservatively (P = 0.26). Combination group patients experienced a mean reduction of -3.1 (95% CI, -3.8 to -2.3) in average arm pain at 1 month versus -1.8 (CI, -2.5 to -1.2) in the conservative group and -2.0 (CI, -2.7 to -1.3) in ESI patients (P = 0.035). For neck pain, a mean reduction of -2.2 (95% CI, -3.0 to -1.5) was noted in combination patients versus -1.2 (CI, -1.9 to -0.5) in conservative group patients and -1.1 (CI, -1.8 to -0.4) in those who received ESI; P = 0.064). Three-month posttreatment, 56.9% of patients treated with combination therapy experienced a positive outcome versus 26.8% in the conservative group and 36.7% in ESI patients (P = 0.006).

CONCLUSIONS

For the primary outcome measure, no significant differences were found between treatments, although combination therapy provided better improvement than stand-alone treatment on some measures. Whereas these results suggest an interdisciplinary approach to neck pain may improve outcomes, confirmatory studies are needed.

Minimally invasive convection-enhanced delivery of biologics into dorsal root ganglia: validation in the pig model and prospective modeling in humans. Technical note

Dorsal root ganglia (DRG) are critical anatomical structures involved in nociception. Intraganglionic (IG) drug delivery is therefore an important route of administration for novel analgesic therapies. Although IG injection in large animal models is highly desirable for preclinical biodistribution and toxicology studies of new drugs, no method to deliver pharmaceutical agents into the DRG has been reported in any large species. The present study describes a minimally invasive technique of IG agent delivery in domestic swine, one of the most common large animal models. The technique utilizes CT guidance for DRG targeting and a custom-made injection assembly for convection enhanced delivery (CED) of therapeutic agents directly into DRG parenchyma. The DRG were initially visualized by CT myelography to determine the optimal access route to the DRG. The subsequent IG injection consisted of 3 steps. First, a commercially available guide needle was advanced to a position dorsolateral to the DRG, and the dural root sleeve was punctured, leaving the guide needle contiguous with, but not penetrating, the DRG. Second, the custom-made stepped stylet was inserted through the guide needle into the DRG parenchyma. Third, the stepped stylet was replaced by the custom-made stepped needle, which was used for the IG CED. Initial dye injections performed in pig cadavers confirmed the accuracy of DRG targeting under CT guidance. Intraganglionic administration of adeno-associated virus in vivo resulted in a unilateral transduction of the injected DRG, with 33.5% DRG neurons transduced. Transgene expression was also found in the dorsal root entry zones at the corresponding spinal levels. The results thereby confirm the efficacy of CED by the stepped needle and a selectivity of DRG targeting. Imaging-based modeling of the procedure in humans suggests that IG CED may be translatable to the clinical setting.

Diagnostic and therapeutic spinal interventions: Epidural injections

Epidural injections of local anesthetic or a corticosteroid are frequently given to diagnose and treat patients with radicular pain originating from any spinal level. The best-quality evidence supports a transforaminal approach in the lumbar spine. Many patients experience substantial benefit from a single therapeutic injection. Depending upon the benefit obtained, additional injections may be administered. Selective nerve blocks with local anesthetic alone can identify the spinal nerve mediating the patient's pain. Serious short-term risks are rare but occur; long-term risks are infrequent and can be due to systemic effects of multiple corticosteroid injections. Patients who have failed conservative therapy or are not candidates for surgical intervention can be considered for epidural steroid injections to relieve their radicular pain temporarily.

The effectiveness and risks of fluoroscopically guided cervical transforaminal injections of steroids: a systematic review with comprehensive analysis of the published data

OBJECTIVE

To determine the effectiveness and risks of fluoroscopically guided cervical transforaminal injection of corticosteroids in the treatment of radicular pain.

DESIGN

Systematic review of the literature with comprehensive analysis of the published data.

INTERVENTIONS

Three reviewers with formal training in evidence-based medicine searched the literature on fluoroscopically guided cervical transforaminal injection of steroids (CTFIS). Each reviewer independently assessed the methodology of studies found and appraised the quality of the evidence presented.

OUTCOME MEASURES

The primary outcome assessed was relief of radicular pain. Other outcomes such as reduction in surgery rate and complications were noted if reported. The evidence on each outcome was appraised in accordance with the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system of evaluating evidence.

RESULTS

The searches yielded 16 primary publications on effectiveness. Available evidence, derived mainly from observational studies, suggests that approximately 50% of patients experience 50% relief of radicular pain for at least 4 weeks after CTFIS, and the intervention may have surgery-sparing effects. The literature also contains 21 articles with primary reports of serious complications, including 13 deaths and many catastrophic neurological injuries. The evidence of pain-relieving effects, of surgery-sparing effects, and of risks of CTFIS were all rated as of very low quality according to the GRADE system.

CONCLUSIONS

In patients with cervical radicular pain, fluoroscopically guided CTFIS may be effective in easing pain and reducing need for surgery. However, the evidence of effectiveness is of very low quality, and the benefits of the procedure are compromised by the risks of serious complications.

Epidural steroids: a comprehensive, evidence-based review

Epidural steroid injections (ESIs) are the most widely utilized pain management procedure in the world, their use supported by more than 45 placebo-controlled studies and dozens of systematic reviews. Despite the extensive literature on the subject, there continues to be considerable controversy surrounding their safety and efficacy. The results of clinical trials and review articles are heavily influenced by specialty, with those done by interventional pain physicians more likely to yield positive findings. Overall, more than half of controlled studies have demonstrated positive findings, suggesting a modest effect size lasting less than 3 months in well-selected individuals. Transforaminal injections are more likely to yield positive results than interlaminar or caudal injections, and subgroup analyses indicate a slightly greater likelihood for a positive response for lumbar herniated disk, compared with spinal stenosis or axial spinal pain. Other factors that may increase the likelihood of a positive outcome in clinical trials include the use of a nonepidural (eg, intramuscular) control group, higher volumes in the treatment group, and the use of depo-steroid. Serious complications are rare following ESIs, provided proper precautions are taken. Although there are no clinical trials comparing different numbers of injections, guidelines suggest that the number of injections should be tailored to individual response, rather than a set series. Most subgroup analyses of controlled studies show no difference in surgical rates between ESI and control patients; however, randomized studies conducted by spine surgeons, in surgically amenable patients with standardized operative criteria, indicate that in some patients the strategic use of ESI may prevent surgery.

Epidural Injections for Spinal Pain

Background:

Epidural steroid injection is the most frequently performed pain procedure. This study of epidural steroid “control” injections aimed to determine whether epidural nonsteroid injections constitute a treatment or true placebo in comparison with nonepidural injections for back and neck pain treatment.

Methods:

This systematic review with direct and indirect meta-analyses used PubMed and EMBASE searches from inception through October 2012 without language restrictions. Study selection included randomized controlled trials with a treatment group receiving epidural injections of corticosteroids or another analgesic and study control groups receiving either an epidural injection devoid of treatment drug or a nonepidural injection. Two reviewers independently extracted data including short-term (up to 12 weeks) pain scores and pain outcomes. All reviewers evaluated studies for eligibility and quality.

Results:

A total of 3,641 patients from 43 studies were included in this systematic review and meta-analysis. Indirect comparisons suggested epidural nonsteroid were more likely than nonepidural injections to achieve positive outcomes (risk ratio, 2.17; 95% CI, 1.87–2.53) and provide greater pain score reduction (mean difference, −0.15; 95% CI, −0.55 to 0.25). In the very limited direct comparisons, no significant differences were noted between epidural nonsteroid and nonepidural injections for either outcome (risk ratio [95% CI], 1.05 [0.88–1.25]; mean difference [95% CI], 0.22 [−0.50 to 0.94]).

Conclusion:

Epidural nonsteroid injections may provide improved benefit compared with nonepidural injections on some measures, though few, low-quality studies directly compared controlled treatments, and only short-term outcomes (≤12 weeks) were examined.

A systematic review of the effectiveness of CT-guided, lumbar transforaminal injection of steroids

OBJECTIVE

To determine the effectiveness and safety of computerized tomography (CT) guided, lumbar transforaminal injection of steroids in the treatment of radicular pain.

DESIGN

Systematic review of published literature.

INTERVENTIONS

Two reviewers independently assessed 19 publications on the effectiveness and safety of CT-guided, lumbar transforaminal injection of steroids.

OUTCOME MEASURES

For effectiveness, the primary outcome was the success rate for relief of pain. For safety, the radiation exposure involved and the nature of complications were determined.

RESULTS

Much of the literature fails to provide evidence. Two studies reported decreases in mean or median pain scores but no other data. Two studies reported success rates of between 34% and 62% for achieving 50% relief of pain at between 1 and 6 months after treatment. CT-guided injections may involve greater radiation exposure than does fluoroscopy-guided injections and do not avoid catastrophic spinal cord injury.

CONCLUSION

The evidence-base for CT-guided lumbar transforaminal injection of steroids is meagre. This intervention is not more effective than fluoroscopy-guided injections and is not demonstrably safer.

The noninferiority of the nonparticulate steroid dexamethasone vs the particulate steroids betamethasone and triamcinolone in lumbar transforaminal epidural steroid injections

OBJECTIVE

To assess whether a nonparticulate steroid (dexamethasone, 10 mg) is less clinically effective than the particulate steroids (triamcinolone, 80 mg; betamethasone, 12 mg) in lumbar transforaminal epidural steroid injections (TFESIs) in subjects with radicular pain with or without radiculopathy.

DESIGN

Retrospective observational study with noninferiority analysis of dexamethasone relative to particulate steroids.

SETTING

Single academic radiology pain management practice.

SUBJECTS

Three thousand six hundred forty-five lumbar TFESIs at the L4-5, L5-S1, or S1 neural foramina, performed on 2,634 subjects.

METHODS/OUTCOME MEASURES

Subjects were assessed with a pain numerical rating scale (NRS, 0-10) and Roland-Morris disability questionnaire (R-M) prior to TFESI, and at 2 weeks and 2 months follow-up. For categorical outcomes, successful pain relief was defined as either ≥50% reduction in NRS or pain 0/10; functional success was defined as ≥40% reduction in R-M score. Noninferiority analysis was performed with δ = -10% as the limit of noninferiority. Continuous outcomes (mean NRS, R-M scores) were analyzed for noninferiority with difference bounds of 0.3 for NRS scores and 1.0 for R-M scores.

RESULTS

With categorical outcomes, dexamethasone was demonstrated to be noninferior to the particulate steroids in pain relief and functional improvement at 2 months. Using continuous outcomes, dexamethasone was demonstrated to be superior to the particulate steroids in both pain relief and functional improvement at 2 months.

CONCLUSION

This retrospective observational study reveals no evidence that dexamethasone is less effective than particulate steroids in lumbar TFESIs performed for radicular pain with or without radiculopathy.