Role of transforaminal epidural injections or selective nerve root blocks in the management of lumbar radicular syndrome - A narrative, evidence-based review

Four-Week Outcomes of Transforaminal Epidural Injections in Patients With Lumbar Radicular Pain

Background Lumbar radicular pain occurs due to irritation or compression of the nerve roots in the lower back. This study aimed to evaluate the efficacy of transforaminal epidural steroid injections (TFESIs) in reducing pain and improving functional outcomes in a diverse patient population with lumbar radicular pain. Methodology This quasi-experimental trial was performed at the Department of Orthopedic Surgery and Traumatology, Unit 1, Mayo Hospital, Lahore, from October 2021 to September 2022. The inclusion criteria comprised patients of either gender experiencing lumbar radicular pain. The demographic and clinical profiles of all participants were recorded using a structured questionnaire. Functional status was assessed using the Oswestry Disability Index (ODI). Pain intensity was evaluated using the Visual Analog Scale (VAS). Lumbar TFESI were administered, consisting of 4 mg dexamethasone and 0.33% lidocaine in a 3 ml solution. Patients were monitored for four weeks post-treatment, and outcomes were reported in the form of pain score (VAS) and ODI score from baseline to four weeks. Secondary outcomes included the rate of return to work, patient satisfaction, and the need for additional analgesic use. Results Of the total 62 patients, 37 (59.7%) were female. The mean age was 53.34±6.84 years. The mean duration of pain was 2.31±0.95 months. Six patients lost follow-up, so those were excluded from the final analysis. The mean pain score significantly reduced from 7.0±0.85 to 1.90 ± 0.65 after four weeks of treatment (p<0.0001). There was a corresponding improvement in ODI scores from 38.5±8.7 to 20.1±5.3 (p<0.0001). Post-treatment, 38 (61.4%) patients were able to return to work within four weeks. Overall, 49 (87.5%) patients reported satisfaction with the treatment. The requirement for rescue analgesia post-injection was significantly lower, with nine (16.1%) patients needing additional pain relief measures (p<0.0001). Conclusion This study demonstrated that lumbar TFESI were effective in significantly reducing pain and improving functional outcomes after a four-week period in patients with lumbar radicular pain.

Transforaminal Steroid Injection After Dorsal Root Ganglion Pulsed Radiofrequency (DRG-PRF): Impact on Pain Intensity and Disability

INTRODUCTION

Dorsal root ganglion pulsed radiofrequency (DRG-PRF) is frequently used for the treatment of chronic lumbar radicular pain with good outcomes in terms of pain management. Transforaminal epidural steroid injection (TFESI) is often administered immediately after DRG-PRF to increase the anti-inflammatory effects, but support for the synergic mechanism is lacking in the literature. The aim of this study was to investigate the potential role of TFESI immediately after DRG-PRF and its possible role on pain intensity and patient disability.

METHODS

A database of patients who underwent DRG-PRF with or without TFESI immediately after DRG-PRF was retrospectively analysed; propensity score matching was applied to the analysis to reduce possible bias. Pain intensity (numerical rating scale [NRS]) and Oswestry disability index (ODI) were recorded pre-operatively and at the 1- and 3-month follow-up in the two groups of patients.

RESULTS

A total of 252 patients were included in this retrospective analysis, 126 patients in the DRG-PRF + TFESI group and 126 patients in the DRG-PRF group after propensity score matching. Both groups displayed a significant reduction in pain intensity (NRS score reduction; p < 0.0001) and improvement in the ODI (p < 0.0001) from baseline at the 3-month follow-up. Interestingly, the use of TFESI after DRG-PRF was not associated with any clinical benefit as no difference in NRS and ODI was found between the two groups at the 1- and 3-month follow-ups.

CONCLUSIONS

Our study revealed a significant pain reduction and disability improvement after DRG-PRF in patients with lumbar radicular pain. Interestingly, no positive role of TFESI immediately after DRG-PRF was observed. These findings suggest that DRG-PRF provides substantial pain relief, and no added benefit is obtained with subsequent steroid injection. Future prospective studies with expanded follow-up periods are needed to confirm these findings.

Outcomes after selective nerve root blockade for lumbar radicular pain from lumbar disc hernia or lumbar spinal stenosis assessed by the PROMIS-29 - a prospective observational cohort study

PURPOSE

Selective nerve root blocks (SNRB) are used both as a therapeutic and diagnostic tool for lumbar radicular pain. Most studies evaluate the effect of SNRB simply by its relation to pain reduction. It is well known that pain is associated with other factors such as depression, anxiety, inactivity and sleeping disorders, but these patient-related outcomes are seldom evaluated. This study evaluated the influence of SNRB on pain-related outcomes including depression, anxiety, fatigue, pain interference, activity and sleep.

METHODS

One hundred three patients with lumbar radicular pain were treated with a SNRB. Patient-reported outcome measures (PROMs) were assessed with the PROMIS-29 for 12 weeks (84 days) following the SNRB. Patients were stratified based on their pain reduction at the 14-day follow up as responders (≥ 30% pain reduction) and non-responders (< 30% pain reduction). Post-treatment duration was estimated with the Kaplan-Meier analysis with return to baseline as an event. A paired t-test was used to compare pre- and post-treatment responses at specific time intervals.

RESULTS

Forty-four percent (n = 45) of the patients were responders and showed significant improvement in all parameters throughout the 84-days follow-up, the exception was sleep that lost significance at day 70. The mean post-treatment duration among responders was 59 (52-67) days. Non-responders showed significant improvements in pain interference and pain intensity until day 35 and in ability for social participation until 21-day.

CONCLUSION

SNRB can improve pain intensity, pain interference, physical function, fatigue, anxiety, depression, sleep disturbance and the ability to participate in social roles.

A novel simplified sonographic approach with fluoroscopy-controlled L5 transforaminal epidural injections in patients with high iliac crest: a retrospective study

BACKGROUND

To explore a novel ultrasound (US) modality for lumbar transforaminal epidural injections (TFEIs) in patients with low back pain (LBP) and L5 radicular pain combined with high iliac crest (HIC).

METHODS

One-hundred and forty-one patients were retrospectively stratified into two groups based on the treatment they received: novel group, receiving US-guided and fluoroscopy (FL)-controlled TFEIs using a sagittal oblique approach between the superior articular process of L5 and S1, and control group, receiving US-guided TFEIs with conventional transverse approach combined with FL confirmation. Accuracy of contrast dispersing into lumbar epidural space was set as the primary endpoint. Radiation dosages, procedure time, numeric rating scale (NRS) scores, Modified Oswestry Disability Questionnaire (MODQ) scores, adverse events, and rescue analgesic requirement were also recorded. The generalized liner mixed model (GLMMs) was employed to compare the repeatedly measured variables between groups, taking individual confounding factors as covariance.

RESULTS

The accuracy of TFEIs was 92.8% and 65.2% in novel and control group, with a significant difference of 26.7% (95% CI: 15.4%, 39.8%) between two modalities (p < 0.001). Significant pain relief was observed in novel group as opposed to control group after one injection. Procedure time in novel group (8.4 ± 1.6 min) was shorter than control group (15.8 ± 3.5 min) (p < 0.001) with less radiation dosage (3047 ± 5670 vs. 8808 ± 1039 μGy/m2, p < 0.001). Significantly, lower incidence of L5 paresthesia occurred in novel group. Statistical differences of NRS scores between the novel and control group were reached at 1 week after procedure (1 (IQR: - 1-3) vs. 3 (IQR: - 1-7), p = 0.006), while not reached at both 1- (1 (IQR: 0-2) vs. 1 (IQR: - 1-3), p = 0.086) or 3-month follow-up (0 (IQR: - 1-1) vs. 1 (IQR: 0-2), p = 0.094). Both groups showed similar functional improvement (F = 0.103, p = 0.749) during follow-up.

CONCLUSIONS

The novel sonographic technique provided superior accuracy needle placement and better pain-relieving effect through one injection as compared to the routine transverse approach. Consequently, in situations where the HIC imposed limitations for TFEIs performance on L5, the novel technique should be recommended to consider increasing accurate puncture, minimizing radiation exposure, consuming procedure time, and reducing the risk of neuraxial injury.

Lumbar Transforaminal Injection of Steroids versus Platelet-Rich Plasma for Prolapse Lumbar Intervertebral Disc with Radiculopathy: A Randomized Double-Blind Controlled Pilot Study

STUDY DESIGN

Double-blind randomized controlled pilot study.

PURPOSE

The purpose of this study was to compare outcomes of steroids with autologous platelet-rich plasma (PRP) administered by lumbar transforaminal injection (LTI) in patients with lumbar radiculopathy.

OVERVIEW OF LITERATURE

Degenerative disc disease of the lumbar spine is one of the most common conditions managed by spine surgeons in routine practice. Once conservative management fails, LTI is diagnostic and often therapeutic. Steroids are the gold standard drug used for LTI but have limitations and side effects.

METHODS

In this single-center double-blind randomized controlled pilot study, 46 patients were recruited and randomized by the lottery method. The Visual Analog Scale (VAS) for leg pain, modified Oswestry Disability Index (mODI), and Short-Form 12 (SF-12) were assessed at 1 week, 3 weeks, 6 weeks, 6 months, and 1 year.

RESULTS

Both groups were comparable in terms of demographics, preprocedure VAS scores, mODI, and SF-12 scores (p=0.52). At the 1-week follow-up, the steroid group had significantly better improvement than the PRP group (p=0.0001). At the 3-week follow-up, both groups showed comparable outcomes; however, the PRP group had better symptom improvement. At 6 weeks and 6 months, the PRP group had better outcomes (VAS, p<0.0001; ODI, p=0.02; SF-12, p=0.002). Moreover, 17 and 16 patients in the steroid and PRP groups underwent repeat LTI with steroids or surgery because of pain recurrence during follow-up. At 1 year, no difference in outcomes was observed.

CONCLUSIONS

PRP may be a useful alternative to steroids for LTI in lumbar radiculopathy. Although improvement was delayed and 1-year outcomes were comparable, the 6-week and 6-month outcomes were better with PRP than with LTI. Multiple PRP injections may be beneficial because of its autologous nature. However, further studies with a larger number of participants, longer follow-up, and repeat LTIs are warranted to draw definite conclusions.

Results from an expedited spinal nerve root block clinic at a UK tertiary neurosurgical centre

STUDY DESIGN

Retrospective Observational Study.

INTRODUCTION

Lumbar radicular pain has a prevalence of 3-5%. Level 1 evidence has demonstrated equivalence between surgical and injection treatment. We assess the outcomes from a transforaminal epidural steroid injection clinic in a tertiary neuroscience referral centre.

METHODS

We performed an analysis of data from consecutive patients entered into a new internal referral database between August 2018 to May 2021. Radicular pain was classified as one of "first presentation" or "recurrence". Outcomes were obtained from follow up clinic letters and recorded in a binary manner of "positive result" or "negative result". Spinal pathology was documented from radiology reports and MRI images.

RESULTS

We analysed 208 patients referred to the clinic. Excluding those who improved to a point of not requiring treatment, and those who underwent surgical intervention, 119 patients undergoing injection were included, of which 14 were lost to follow-up. 68 % of patients had a positive result from injection. Subgroup analysis demonstrated good outcomes for both hyperacute (<6 weeks) and chronic (>12 months). Contained disk pathologies had better outcomes than uncontained. There was no difference in outcomes across grades of compression, but previous same level surgery was associated with poorer response rates.

CONCLUSIONS

There is a high rate of natural resolution of symptoms in patients with LSRP. In those where pain persists, TFESI is a valuable first line treatment modality. This study suggests the efficacy of TFESI is potentially independent of grade of stenosis and chronicity of symptoms. Contained disc pathologies respond better than uncontained.

Clinical outcomes of 3T magnetic resonance imaging-guided lumbar and sacral foraminal injections

PURPOSE

This article evaluates the feasibility, safety, and efficacy of MRI-guided lumbar or sacral nerve root infiltration for chronic back pain. We compared the outcomes of our MRI-guided infiltrations with data from CT-guided infiltrations reported in the literature and explored the potential advantages of MRI guidance.

METHOD

Forty-eight MRI-guided nerve root infiltrations were performed using a 3 T MRI machine. The optimal needle path was determined using breathhold T2-weighted sequences, and the needle was advanced under interleaved guidance based on breathhold PD-weighted images. Pain levels were assessed using a numeric rating scale (NRS) before the procedure and up to 5 months after, during follow-up. Procedure success was evaluated by comparing patients' pain levels before and after the infiltration.

RESULTS

The MRI-guided infiltrations yielded pain reduction 1 week after the infiltration in 92% of cases, with an average NRS substantial change of 3.9 points. Pain reduction persisted after 5 months for 51% of procedures. No procedure-related complications occurred. The use of a 22G needle and reconstructed subtraction images from T2 FatSat sequences improved the workflow.

CONCLUSION

Our study showed that MRI-guided nerve root infiltration is a feasible, safe, and effective treatment option for chronic back pain. Precise positioning of the needle tip and accurate distribution of the injected solution contributed to the effectiveness of MRI-guided infiltration, which appeared to be as accurate as CT-guided procedures. Further research is needed to explore the potential benefits of metal artifact reduction sequences to optimize chronic back pain management.

Transforaminal Injections of Platelet-Rich Plasma Compared with Steroid in Lumbar radiculopathy: A Prospective, Double-Blind Randomized Study

Purpose

To evaluate and compare the clinical efficacy of transforaminal steroid and platelet-rich plasma (PRP) injections in patients with discogenic lumbar radiculopathy.

Methods

60 patients were randomized to be treated with single transforaminal injection of PRP (n = 29) or steroid (methylprednisolone acetate [n = 31]). Clinical assessment was done with Visual analogue scale (VAS), modified Oswestry low back pain disability index (MODI), and straight leg raise test (SLRT). Baseline assessment of outcomes was done followed by post-intervention evaluation at 1, 3, and 6 months. Both groups had similar baseline characteristics.

Results

There was a significant statistical improvement of VAS and MODI in both groups at follow-up (P < 0.05). In PRP group, minimal clinically important change (> 2 cm difference of mean for VAS and > 10-point change in MODI) for both outcome scores was achieved at all follow-up intervals (1, 3, 6 months), while as in steroid group, it was seen only at 1 and 3 months for both VAS and MODI. On intergroup comparison, better results were seen in steroid group at 1 month (P < 0.001 for both VAS and MODI), and in PRP group at 6 months (P < 0.001 for both VAS and MODI) with non-significant difference at 3 months (P = 0.605 for MODI and P = 0.612 for VAS). More than 90% tested SLRT negative in PRP group and 62% in steroid group at 6 months. No serious complications were seen.

Conclusion

Transforaminal injections of PRP and steroid improve short-term (up to 3 months) clinical outcome scores in discogenic lumbar radiculopathy, but clinically meaningful improvements sustaining for 6 months were provided by PRP only.

Ultrasound-guided transforaminal epidural injection with fluoroscopy confirmation for the treatment of unilateral lumbar radiculopathy: A randomized controlled non-inferiority study

BACKGROUND

Ultrasound (US)-guided injections for chronic pain has multiple advantages over traditional radiologic method. The study was performed to exam the clinical outcomes of lumbar transforaminal epidural injection (LTFEI) between US and fluoroscopy (FL) guidance for lumbar radiculopathy (LRP).

METHODS

A total of 164 patients with LRP were randomly assigned into US and FL group to receive LTFEI in a 1:1 ratio. Pain relief and functional disability were assessed by numeric rating scale (NRS) and Modified Oswestry Disability Questionnaire (MODQ) scores before treatment, 1 month and 3 months post-intervention. Contrast spread pattern, fluoroscopic image number and complications were also recorded. The primary outcome was accurate rate of contrast dispersing into lumbar epidural space, and non-inferiority margin was predefined at -15 %.

RESULTS

The accuracy of LTFEI was 90.2 % and 91.5 % in US and FL group, and the lower limit of the 95 %CI of mean difference between two modalities (-4.9 % (95 %CI: -12.8 %, 3.1 %)) was above the non-inferiority margin. Procedure time in US group (531.90 ± 67.12 s) was shorter than FL group (904.20 ± 120.20 s) (p < 0.05), while radiation dosage in the US group was lower than in the FL group (3047.20 ± 569.53 vs. 8807.50 ± 1039.10 μGy m², p < 0.001). Both groups didn't differ in pain reduction (F = 1.050, p = 0.306) and functional improvement (F = 0.103, p = 0.749) during follow-up period. No severe complications occurred in both groups.

CONCLUSIONS

US-guided LTFEI confirmed by FL was not inferior to conventional FL method in terms of accurate rate of lumbar epidural contrast dispersion. Effective pain relief and functional ability improvement were comparable between two modalities, and US technique had advantages of less radiation exposure and possible facilitation of avoiding critical vessels around intervertebral foramen.

Changes in pain scores and walking distance after transforaminal epidural steroid injection in patients with lumbar foraminal spinal stenosis

Transforaminal epidural steroid injections (TFESI) are widely used in patients with lumbar foraminal spinal stenosis. Previous studies have evaluated the effects of TFESI on lumbar foraminal spinal stenosis using only pain scores. However, no study has evaluated the effect of TFESI on pain scores and walking distance in patients with lumbar foraminal spinal stenosis. This study aimed to assess the effect of TFESI on pain scores and walking distance in patients with lumbar foraminal spinal stenosis stratified according to disease severity. This retrospective study reviewed the medical records of patients who received TFESI for lumbar foraminal spinal stenosis. A total of 128 patients were divided into the moderate and severe groups based on the extent of fat obliteration and the presence of nerve root compression. A significant decrease in the numeric rating scale (NRS) scores was observed in the moderate and severe groups compared with the corresponding baseline values 4 weeks after TFESI; however, the NRS pain scores were lower in the moderate group than those in the severe group. In addition, the proportion of patients who experienced pain reduction (≥50%) was higher in the moderate group than that in the severe group. The moderate and severe groups showed a significant increase in walking distance compared with the baseline values 4 weeks after the treatment. However, the walking distance values did not differ significantly between the moderate and severe groups. Furthermore, the degree of satisfaction was higher in the moderate group than that in the severe group. Lumbar TFESI may reduce pain scores and increase walking distance in patients with moderate or severe lumbar foraminal spinal stenosis. Patients with moderate foraminal stenosis had better pain relief outcomes than those with severe foraminal stenosis.

Selective Nerve Root Block in Treatment of Lumbar Radiculopathy: A Narrative Review

Selective Nerve Root Block (SNRB) is a precise local injection technique that can be utilised to target a particular inflamed nerve root causing lumbar radiculopathy for both diagnostic and therapeutic purposes. Usually, for SNRB to be therapeutic, a combination of a local anaesthetic agent and a steroid is injected under imaging guidance, whereas for diagnostic purposes, just the local anaesthetic agent is injected. While the ideal treatment strategy is to relieve the nerve root from its compressing pathology, local injection of steroids targeted at the affected nerve root can also be attempted to reduce inflammation and thus achieve pain relief. Although the general principle for administering an SNRB remains largely the same across the field, there are differences in techniques depending on the region and level of the spine that is targeted. Moreover, drug combinations utilised by clinicians vary based on preference. The proven benefits of SNRBs largely outweigh their risks, and the procedure is deemed safe and well tolerated in a majority of patients. In this narrative, we explore the existing literature and seek to provide a comprehensive understanding of SNRB as a treatment for lumbar radiculopathy, its indications, techniques, outcomes, and complications.

CT-guided transforaminal epidural steroid injection for discogenic lumbar radiculopathy: influence of contrast dispersion and radiologist's experience on clinical outcome

OBJECTIVE

To investigate the impact of contrast dispersion pattern/location during lumbar CT-guided transforaminal epidural steroid injection (TFESI) and experience of the performing radiologist on therapeutic outcome.

MATERIALS AND METHODS

In this single-center retrospective cohort study, two observers analyzed contrast dispersion during CT-guided TFESI of 204 patients (age 61.1 ± 14 years) with discogenic unilateral single-level L4 or L5 radiculopathy. The contrast dispersion pattern was classified as "focal," "linear," or "tram-track"; the location was divided into "extraforaminal," "foraminal," or "recessal." Pain was assessed before and 4 weeks after treatment using a numerical rating scale (0, no pain; 10, intolerable pain). Additionally, the patient global impression of change (PGIC) was assessed. The TFESI was performed by musculoskeletal radiologists (experience range: first year of musculoskeletal fellowship training to 19 years). Contrast pattern/location and radiologist's experience were compared between "good responder" (≥ 50% pain reduction) and "poor responder" (< 50%). A p-value < 0.05 was considered to be statistically significant.

RESULTS

Overall, CT-guided TFESI resulted in a substantial pain reduction in 46.6% of patients with discogenic radiculopathy. The contrast dispersion pattern and location had no effect on pain relief (p = 0.75 and p = 0.09) and PGIC (p = 0.70 and p = 0.21) 4 weeks after TFESI. Additionally, the experience of the radiologist had no influence on pain reduction (p = 0.92) or PGIC (p = 0.75). Regarding pre-interventional imaging findings, both the location and grading of nerve compression had no effect on pain relief (p = 0.91 and p = 0.85) and PGIC (p = 0.18 and p = 0.31).

CONCLUSION

Our results indicate that neither contrast agent dispersion/location nor the experience of the radiologist allows predicting the therapeutic outcome 4 weeks after the procedure.