Ideal Corticosteroid Choice for Epidural Steroid Injections: A Review of Safety and Efficacy

Spinal Injections

Spinal pain is a common complaint and cause of disability in the United States, affecting most individuals at some point in their lives. The complex anatomy of the spine leads to multiple potential and coexisting etiologies for pain, and the differentiation of these sources can present a diagnostic challenge. Image-guided spinal injections can provide both diagnostic information identifying pain location as well as prolonged therapeutic relief as an alternative to medical management. Anesthetic and corticosteroid medications can be administered within the epidural space through transforaminal or interlaminar approaches, blocking various sensory nerves, or directly within the facet joints. Proceduralists must be aware of associated patient considerations, techniques, and potential complications to perform the procedures safely. We discuss image-guided spinal injection techniques, based on best practices and our experiences.

The Immediate Adverse Events of Lumbar Interventional Pain Procedures in 4209 Patients; an Observational Clinical Study

OBJECTIVE

Lumbar interventional pain procedures (LIPP) are frequently used in low back pain and show an increasing trend in recent years. LIPP are highly effective when performed by properly trained physicians. However, some adverse events are seen during interventional procedures. Our aim in this study is to determine the immediate adverse events rates of LIPP and to inform our colleagues about possible adverse events.

STUDY DESIGN

Retrospective, observational study.

SETTING

A university hospital pain management center.

METHODS

After approval of the institutional ethics committee, a retrospectively evaluation of patients, who received fluoroscopy guided LIPP between January 2015 and December 2020, were performed. This observational study was conducted with 4209 patients who underwent LIPP including epidural steroid injections, sacroiliac and facet joint injections, medial branch blocks or RF, dorsal root ganglion pulse RF, epidural catheter or spinal cord stimulator applications.

RESULTS

No major adverse events were detected during the procedures. Minor adverse events were detected in a 60 patients and adverse events rate was found to be 1.4% (95% confidence interval [CI]: 1.0-1.8%). Minor adverse events rates vary between 0.7-2.3% according to the procedures type. The most common adverse events was determined as vasovagal reactions (26/60). Facial numbness, cramps, and seizures were detected as rare adverse events.

CONCLUSION

There were no major adverse events were seen during 4209 patients. The rate of minor adverse events were 1.4% with no sequelae in any of the events. When evidence-based guidelines are followed, interventional pain procedures are performed safely.

Ultrasound-Guided Caudal Epidural Steroid Injection for Back Pain: A Case Report of Successful Emergency Department Management of Radicular Low Back Pain Symptoms

BACKGROUND

Radicular low back pain is difficult to treat and commonly encountered in the Emergency Department (ED). Pain associated with acute radiculopathy results in limited ability to work, function, and enjoy life, and is associated with increased risk of chronic opioid therapy. In this case report, we describe the first ED-delivered ultrasound-guided caudal epidural steroid injection (ESI) used to treat medication-refractory lumbar radiculopathy, which resulted in immediate and sustained resolution of pain.

CASE REPORT

A 56-year old man with a past medical history of chronic lumbar radiculopathy presented to the ED with acute low back and right lower-extremity pain. Based on history and physical examination, a right L5 radiculopathy was suspected. His pain was poorly controlled despite multimodal analgesia, at which point he was offered admission or an ultrasound-guided caudal ESI. The procedure was performed using dexamethasone, preservative-free normal saline, and preservative-free 1% lidocaine solution, after which the patient reported 100% resolution of his pain and requested discharge from the ED. Why Should an Emergency Physician Be Aware of This? The safety and efficacy of ultrasound-guided caudal ESIs have been established, but there is a paucity of literature exploring their application in the ED. We present a case of a refractory lumbar radiculopathy successfully treated with an ultrasound-guided caudal ESI. ED-performed epidurals can be one additional tool in the emergency physician arsenal to treat acute or chronic lumbar radiculopathy.

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.

Can High-Sensitivity C-Reactive Protein Levels Predict Functional Outcome Following Epidural Steroid Injection in Patients with Lumbar Disc Disease?

Study Design

Prospective cohort study.

Purpose

Inflammatory cytokines produced at the site of disc herniation are considered as pain generators in patients with lumbar disc disease. Whether a high-sensitivity C-reactive protein (hs-CRP) assay can be used in order to predict the quantum of inflammation surrounding nerve roots is a matter of investigation. This study aimed to evaluate the association of hs-CRP level and functional outcomes measured by the Modified Oswestry Low Back Pain Disability Questionnaire (MODY) before and after epidural steroid injection (ESI) in patients with lumbar disc disease.

Overview of Literature

Although many studies examining the role of hs-CRP levels and lumbar pain have been published previously, the results are equivocal, and there is no clear consensus regarding which patients will benefit from an ESI.

Methods

This was a prospective study, with 77 patients in the study group and 23 participants in the control group. Baseline hs-CRP levels were obtained for both groups. Study group patients received a single ESI and were subjected to detailed pre- and post-procedure evaluation using MODY scores. For this group, hs-CRP levels were measured at 1 and 2 months after injection.

Results

Out of 77 patients, 52 had acute and 25 had chronic low back pain. Thirty-six patients with acute pain obtained significant improvement, while 16 had an insignificant response to the ESI. None of the chronic cases had a significant response. The mean baseline hs-CRP (mg/L) among the study group (29.83±10.43) was significantly higher than for the controls (10.26±2.783). The baseline hs-CRP among acute cases, where post ESI MODY score at 2 months had significant reduction, was 32.19±5.126, and those with insignificant reduction was 18.13±7.949 (p<0.001).

Conclusions

Baseline hs-CRP levels can be used to prognosticate the outcome following ESI in patients with acute lumbar disc disease, with radicular pain refractory to physiotherapy and analgesics.

The safety and efficiency of performing cervical transforaminal epidural steroid injections under fluoroscopic control on an ambulatory/outpatient basis

PURPOSE

Cervical transforaminal epidural steroid injections (CTFESIs) have become an increasingly utilised means of treating radicular pain over recent decades, although a number of reports have brought their safety into question. Much of this has been attributed to the use of particulate steroids and the theoretical risk of embolic complications with inadvertent intra-arterial injection. This study documents the complications encountered at our centre when performing CTFESI over a more than 10-year study period with predominant use of particulate steroid. Our procedural technique is also described. This study aims to highlight the importance of operator technique first and foremost and how, with safe and reproducible technique that confidently avoids intra-arterial injection, CTFESI can be performed safely irrespective of the choice of steroid.

METHODS

All patients undergoing CTFESI between January 2008 and August 2018 at our centre were prospectively recruited to the study, documenting total number of injections/procedures per patient, presence of/description of complications and severity and type of steroid administered.

RESULTS

Five hundred and twenty-seven patients underwent 1047 procedures (1753 individual cervical levels injected) over the study period: 1011 procedures performed with particulate steroid (triamcinolone acetonide) and 36 performed with non-particulate (dexamethasone). Only six complications were encountered, all spontaneously self-resolving without intervention and considered minor (grade 1).

CONCLUSIONS

With fastidious safe technique, CTFESI can be safe, efficacious and cost-effectively administered on an outpatient basis. Predominant use of particulate steroids did not lead to any significant complications. These slides can be retrieved under Electronic Supplementary Material.

Dilution and microfiltration of particulate corticosteroids for spinal epidural injections: impact on drug concentration and agglomerate formation

Particulate corticosteroids have been described to lead to greater pain improvement compared with their non-particulate counterparts when used in epidural injections. It is hypothesised that filtering may significantly impact their concentration and long-term efficacy. We investigated if passing particulate suspensions through different commonly-used filters affects drug dosage. Two particulate corticosteroid formulations, triamcinolone acetonide and methylprednisolone acetate, were mixed at different concentrations with either bupivacaine hydrochloride or 0.9% sodium chloride. Solutions were passed through a 5-μm and a 0.2-μm filter. Mass spectroscopy results indicated a complete loss of corticosteroid from the solutions using both filters, and light microscopy imaging demonstrated agglomerate formation, suggesting that filtering interferes with drug dosage. The choice of diluents must also be considered to reduce large agglomerate formation. Clinicians should be aware of the consequences of filtering particulate suspensions and carefully consider the selection of diluent when considering treatment plans.

Mineralocorticoid Antagonist Improves Glucocorticoid Receptor Signaling and Dexamethasone Analgesia in an Animal Model of Low Back Pain

Low back pain, a leading cause of disability, is commonly treated by epidural steroid injections that target the anti-inflammatory glucocorticoid receptor (GR). However, their efficacy has been controversial. All currently used epidural steroids also activate the pro-inflammatory mineralocorticoid receptor (MR) with significant potency. Local inflammation of the dorsal root ganglia (DRG), a rat model of low back pain, was used. This model causes static and dynamic mechanical allodynia, cold allodynia and guarding behavior (a measure of spontaneous pain), and activates the MR, with pro-nociceptive effects. In this study, effects of local Dexamethasone (DEX; a glucocorticoid used in epidural injections), and eplerenone (EPL; a second generation, more selective MR antagonist) applied to the DRG at the time of inflammation were examined. Mechanical and spontaneous pain behaviors were more effectively reduced by the combination of DEX and EPL than by either alone. The combination of steroids was particularly more effective than DEX alone or the model alone (3-fold improvement for mechanical allodynia) at later times (day 14). Immunohistochemical analysis of the GR in the DRG showed that the receptor was expressed in neurons of all size classes, and in non-neuronal cells including satellite glia. The GR immunoreactivity was downregulated by DRG inflammation (48%) starting on day 1, consistent with the reduction of GR (57%) observed by Western blot, when compared to control animals. On day 14, the combination of DEX and EPL resulted in rescue of GR immunoreactivity that was not seen with DEX alone, and was more effective in reducing a marker for satellite glia activation/neuroinflammation. The results suggest that EPL may enhance the effectiveness of clinically used epidural steroid injections, in part by enhancing the availability of the GR. Thus, the glucocorticoid-mineralocorticoid interactions may limit the effectiveness of epidural steroids through the regulation of the GR in the DRG.

Percutaneous ozone nucleolysis for lumbar disc herniation

PURPOSE

All percutaneous minimally invasive disc treatments are typically indicated to contained disc herniations. Our study's aim is to evaluate prospectively the efficacy of ozone nucleolysis in the treatment of either contained or uncontained lumbar disc herniations.

METHODS

Fifty-two patients, aged 27-87 years, with symptomatic herniated lumbar discs, without migration, sequestration, or severe degenerative disc changes, who failed conservative treatment, were included in our study. The patients underwent fluoroscopic-guided intradiscal oxygen-ozone mixture injection (5 ml) at a concentration of 27-30 μg/ml and periradicular injection of the same O2-O3 mixture (10 ml), steroid (1 ml), and local anesthetic (1 ml). Clinical outcomes were evaluated, based on the Oswestry Disability Index (ODI) and pain intensity (0-5) scale results, obtained initially and at 2- and 6-month controls. Our results were analyzed by ANOVA and chi-squared (χ2) tests.

RESULTS

Our initial results obtained at 2-month control were promising, indicating a significant decrease in pain disability and intensity in 74% (37) and 76% (38) of the patients respectively, and minimally increased to 76% (38) and 78% (39) at 6-month control (P < 0.001 and CI 99.9%). The mean preprocedure ODI and pain intensity scores were 35 ± 14.36 and 2.38 ± 0.90, respectively, which were reduced to 19.36 ± 13.12 and 1.04 ± 0.92 at 6-month control. Our failure had been mostly related to long symptoms duration of more than 1 year. No complications were recorded.

CONCLUSION

Ozone nucleolysis is a safe cost-effective minimally invasive technique for treatment of contained and uncontained lumbar disc herniations.