Access routes and reported decision criteria for lumbar epidural drug injections: a systematic literature review

Systematic review of the effectiveness of caudal epidural steroid injections in the treatment of chronic low back or radicular pain

Objective

Determine the efficacy, effectiveness, and safety of fluoroscopically- or ultrasound-guided caudal epidural steroid injections (ESIs) with or without catheter placement for the treatment of chronic low back (CLBP), radicular pain, and/or chronic post-surgical back pain (CPSBP).

Design

Systematic review.

Population

Adults ≥18 years with CLBP, radicular pain, or CPSBP ≥3 months.

Intervention

Fluoroscopically- or ultrasound-guided caudal ESI with or without a catheter including epidural neuroplasty.

Comparison

Sham, placebo procedure, active standard care treatment, or none.

Outcomes

The primary outcome was the proportion of individuals with reduction of pain by ​≥ ​50%. Secondary outcomes included functional improvement, analgesic use, subsequent spinal surgery, healthcare utilization, and mean improvement in pain. Reported adverse events were also cataloged.

Methods

Four reviewers independently assessed publications before January 2, 2022 in PubMed, Ovid MEDLINE, and Scopus. Quality of evidence was evaluated using the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework.

Results

Of 364 records screened, 23 publications met inclusion criteria. The success rates for the primary outcome could only be extrapolated from one study. Another study used a composite improvement scale that included pain and functional outcomes. The reported success rates in these two studies ranged from 40 to 58% at three months, 25%-67% at six months, and 58%-61% at one year. Data on secondary outcomes were limited; however, rates of functional improvement as measured by mean improvement in Oswestry Disability Index (ODI) ranged from 2% to 55%.

Conclusion

There is moderate-quality evidence that caudal ESIs using an in-dwelling catheter for two days is an effective treatment for pain and dysfunction associated with disc herniation with radicular pain and for CPSBP at three, six, and 12 months. There is low-quality evidence supporting the effectiveness of other caudal ESI techniques for pain and dysfunction associated with central lumbar spinal stenosis with neurogenic claudication, discogenic CLBP, and CLBP without disc herniation or radiculitis.

Transforaminal Intrathecal Access for Injection of Nusinersen in Adult and Pediatric Patients with Spinal Muscular Atrophy

The main purpose of this article is to assess the safety and efficacy of transforaminal lumbar puncture for the injection of nusinersen (Spinraza) in patients with extensive spinal fusion and/or scoliosis.

A retrospective chart reviews of all spinal muscular atrophy patients (adults and children) were conducted. Demographic data, procedure details, follow-ups, and related complications were recorded.

We performed 85 transforaminal injections in nine pediatric patients (5 male and 4 female) aged between 8 and 17 years (mean = 11 years) and seven adult patients (5 females and 2 males) aged between 24 and 41 years (mean= 30 years). Fluoroscopy guidance was used in 87% of our patients. No major complication was reported.

Fluoroscopy-guided transforaminal nusinersen injection is a safe and successful alternative approach in adult and pediatric patients with severe spinal scoliosis, interlaminar osseous fusion, and spinal fusion hardware.

Rare Neurosurgical Complications of Epidural Injections: An 8-Yr Single-Institution Experience

BACKGROUND

Neurosurgical complications from epidural injections have rarely been reported.

OBJECTIVE

To define the spectrum of complications from these procedures in order to identify risk factors and strategies for prevention.

METHODS

A prospectively maintained database of 14 247 neurosurgical admissions over 8 yr was screened to identify patients who had suffered procedural complications associated with 1182 cervical and 4617 lumbar interlaminar epidural injection procedures performed at a single institution. Patients who developed new neurological symptoms or deficits were included. A retrospective analysis of demographic and procedural features was performed.

RESULTS

Thirteen patients experienced complications requiring neurosurgical treatment, accounting for an overall procedural complication rate of 0.22% (0.51% and 0.15% for cervical and lumbar injections, respectively), and representing 0.09% of all neurosurgical admissions over 8 yr. There were 3 categories: hemorrhage (n = 7), infection (n = 3), and inadvertent dural penetration (n = 3). There was significant association with anticoagulation use among patients with hemorrhagic vs nonhemorrhagic complications ( P < .01, Fisher's exact test). Six patients who developed epidural hematoma had been managed in accordance with current guidelines, either after prolonged cessation of anticoagulation (n = 3) or taking only aspirin (n = 3); all were decompressed promptly with good long-term outcome. All infections were associated with lumbar injection. Dural penetration resulted in diffuse pneumocephalus (n = 1), intramedullary air at the site of injection (n = 1), and acutely symptomatic colloid cyst (n = 1).

CONCLUSION

A majority of neurosurgical complications from epidural injections are hemorrhagic and associated with anticoagulation, although infection and inadvertent dural penetration also occur. Prompt treatment of compressive lesions is associated with good outcome.

Intrathecal administration of nusinersen in adolescent and adult SMA type 2 and 3 patients

Spinal muscular atrophy is a genetic motor neuron disease that leads to progressive muscular atrophy and muscle weakness. In December 2016, the Food and Drug Administration, and in June 2017, the European Medicines Agency approved the antisense oligonucleotide nusinersen for treatment of spinal muscular atrophy. Nusinersen has to be repeatedly administered intrathecally. Due to the clinical features of SMA, the application of the ASO by lumbar puncture can be challenging in symptomatic patients considering the frequently observed scoliosis, previous spine fusion surgeries, joint contractures, and respiratory insufficiency. To evaluate safety and feasibility of the intrathecal treatment in adolescent and adult SMA type 2 and 3 patients, we analyzed 93 lumbar punctures, monitored number of lumbar puncture attempts, duration of the procedure, injection site, and needle length. Oxygen saturation during the intervention, medication for sedation and local anesthesia, adverse events related to lumbar punctures, and macroscopic analysis of CSF were recorded. Moreover, we analyzed the use of CT-scans for performing lumbar punctures and its associated radiation exposure. Performing lumbar puncture for the intrathecal administration of nusinersen in adolescent and adult patients with later-onset SMA is feasible and safe, even in patients with complex spinal anatomies and respiratory insufficiency. To guarantee the quality of the procedure, we recommend establishing an experienced interdisciplinary team consisting of neurologists and/or neuropediatricians, anesthesiologists, orthopedic surgeons, and/or neuroradiologists.

Transforaminal intrathecal delivery of nusinersen using cone-beam computed tomography for children with spinal muscular atrophy and extensive surgical instrumentation: early results of technical success and safety

BACKGROUND

Nusinersen, the only treatment approved by the United States Food and Drug Administration for spinal muscular atrophy (SMA), is delivered intrathecally. Many children with SMA have extensive spinal instrumentation and deformities, often precluding the use of standard approaches for gaining intrathecal access. Furthermore the anatomical distortion that often occurs with rotoscoliosis can complicate the use of fluoroscopic guidance. Compared to fluoroscopy, CT affords superior guidance for complex needle placements. This opens up alternatives to the posterior (interlaminar) technique, including transforaminal and caudal approaches.

OBJECTIVE

This study describes the early results of technical success, complications and radiation dose of intrathecal delivery of nusinersen using cone-beam CT guidance with two-axis fluoroscopic navigational overlay.

MATERIALS AND METHODS

We conducted a retrospective review of 15 consecutive nusinersen injections performed in four children with SMA and extensive spinal hardware precluding standard posterior lumbar puncture techniques. These children were treated using transforaminal thecal access employing cone-beam CT with navigational overlay. We analyzed results including technical success, complications and total fluoroscopy time.

RESULTS

All procedures were technically successful. No major complications and one minor complication were reported; the minor complication was a post-procedural neuropathic headache that was attributed to procedural positioning and was treated successfully with gabapentin. The average procedural fluoroscopy time and air kerma were 1.9 min and 55.8 mGy, respectively.

CONCLUSION

Cone-beam CT guidance with two-axis navigational overlay is a safe, effective method for gaining transforaminal intrathecal access in children with spinal abnormalities and hardware precluding the use of standard techniques.

Periradicular infiltration of the lumbar spine: testing the robustness of an interventional ultra-low-dose protocol at different body mass index levels

Background Computed tomography (CT)-guided periradicular infiltration remains a frequent interventional procedure for treatment of low back pain. Purpose To present an interventional ultra-low-dose protocol for CT-guided periradicular infiltration therapy and assess its application at different body mass index (BMI) levels. Material and Methods Over a period of 14 months, 79 patients underwent 183 CT-guided interventions for single-site lumbar periradicular therapy using an ultra-low-dose protocol with a basic setup of 100 kV and 5 mAs. Procedures were performed via intermittent fluoroscopy. A retrospective review was performed to analyze the parameters tube current and tube voltage, dose-length product, and BMI. Results The interventional ultra-low-dose protocol allowed safe treatment of 91.1% of the patients without a need for adapting the protocol. In seven patients with a higher BMI (range, 31-38 kg/m²; mean, 34 kg/m²), the tube current had to be increased to retain sufficient image quality. Only patients with a BMI of 30 and higher showed a significant correlation between BMI and dose-length product ( P value = 0.02), resulting in a slightly increased dose ( P value = 0.002). Conclusion The protocol presented for the interventional part of CT-guided periradicular infiltration allows to safely treat patients with a median calculated effective dose of 0.045 mSv (converted from a dose-length-product of 2.26 mGy*cm). Patients with a BMI of 30 and higher required a higher calculated effective dose with just one patient slightly exceeding 0.1 mSv.

Ultra-low-dose periradicular infiltration of the lumbar spine: spot scanning and its potential for further dose reduction by replacing helical planning CT

PURPOSE

Computed tomography (CT)-guided periradicular infiltration has become an accepted procedure for treating radiculopathy-associated low back pain. The purpose of this study is to compare spot scanning and segmental helical planning CT in terms of dose reduction.

MATERIALS AND METHODS

Eighty-five patients underwent CT-guided single-site lumbar periradicular therapy. Prior imaging was not available for planning. Sixty-three patients were examined with a new dedicated spot scanning technique (group I), and twenty-two patients underwent conventional segmental planning CT examinations with helical image acquisition serving as controls (group II). Examinations were reviewed retrospectively for dose-length product (DLP) and number of acquisitions required for intervention. Pain reduction accomplished with the intervention was recorded for quality assurance.

RESULTS

Median DLP was 0.80 mGy cm for spot scanning versus 6.50 mGy cm for segmental planning CT. Thus, the contribution of the planning scan to the total interventional dose decreased from 73 to 25%. As a result, the total interventional dose was reduced significantly from a median DLP of 8.90 mGy cm to 3.20 mGy cm (-64%). Acquisitions required during the intervention had a median DLP of 2.40 mGy cm for group I and 2.35 mGy cm for group II, showing no significant difference. Median pain reduction in both groups was two points on the numeric rating scale.

CONCLUSION

Dedicated spot scanning for planning reduced the total median effective dose of the intervention by more than 64% without increasing the number of images required during the interventional procedure. Significant pain reduction was achieved with both approaches. Spot scanning is recommended for dose reduction.

Selective nerve root blocks vs. caudal epidural injection for single level prolapsed lumbar intervertebral disc - A prospective randomized study

BACKGROUND

Chronic lumbar radiculopathy has a lifetime prevalence of 5.3% in men and 3.7% in women. It usually resolves spontaneously, but up to 30% cases will have pronounced symptoms even after one year.

AIMS

A prospective randomized single-blind study was conducted to compare the efficacy of caudal epidural steroid injection and selective nerve root block in management of pain and disability in cases of lumbar disc herniation.

METHODS

Eighty patients with confirmed single-level lumbar disc herniation were equally divided in two groups: (a) caudal epidural and (b) selective nerve root block group, by a computer-generated random allocation method. The caudal group received three injections of steroid mixed with local anesthetics while selective nerve root block group received single injection of steroid mixed with local anesthetic agent. Patients were assessed for pain relief and reduction in disability.

RESULTS

In SNRB group, pain reduced by more than 50% up till 6 months, while in caudal group more than 50% reduction of pain was maintained till 1 year. The reduction in ODI in SNRB group was 52.8% till 3 months, 48.6% till 6 months, and 46.7% at 1 year, while in caudal group the improvement was 59.6%, 64.6%, 65.1%, and 65.4% at corresponding follow-up periods, respectively.

CONCLUSIONS

Caudal epidural block is an easy and safe method with better pain relief and improvement in functional disability than selective nerve root block. Selective nerve root block injection is technically more demanding and has to be given by a skilled anesthetist.

The Effectiveness of Transforaminal Versus Caudal Routes for Epidural Steroid Injections in Managing Lumbosacral Radicular Pain: A Systematic Review and Meta-Analysis

Epidural steroid injection (ESI) is one of the most commonly used treatments for radiculopathy. Previous studies have described the effectiveness of ESI in the management of radiculopathy. However, controversy exists regarding the route that is most beneficial and effective with respect to the administration of epidural steroids, as both transforaminal (TF) and caudal (C) routes are commonly used.This analysis reviewed studies comparing the effectiveness of TF-ESIs with that of C-ESIs in the treatment of radiculopathy as a means of providing pain relief and improving functionality. This meta-analysis was performed to guide clinical decision-making.The study was a systematic review of comparative studies.A systematic literature search was performed using the PubMed, EMBASE, and Cochrane Library databases for trials written in English. The randomized trials and observational studies that met our inclusion criteria were subsequently included. Two reviewers, respectively, extracted data and estimated the risk of bias. All statistical analyses were performed using Review Manager 5.3.Six prospective and 2 retrospective studies involving 664 patients were included. Statistical analysis was performed utilizing only the 6 prospective studies. Although slight pain and functional improvements were noted in the TF-ESI groups compared with the C-ESI groups, these improvements were neither clinically nor statistically significant.The limitations of this meta-analysis resulted primarily from the weaknesses of the comparative studies and the relative paucity of patients included in each study.Both the TF and C approaches are effective in reducing pain and improving functional scores, and they demonstrated similar efficacies in the management of lumbosacral radicular pain.