Role of Magnetic Resonance Imaging in Ascertaining the Success of Transforaminal Epidural Steroid Injection for Lumbar Radicular Pain

Clinical Effectiveness of Single Lumbar Periradicular Infiltration in Patients with Sciatica

Periradicular therapy (PRT) is a minimally invasive radiological procedurein patients with chronic lumbar pain.The aim of the study is to identify clinical and radiological predictive factors for treatment success after a single PRT treatment in patients with sciatica.The study includes a prospective follow-up of 166 patients treated with PRT. The pain intensity is determined according to the VAS scale and the degree of improvement is presented as excellent (over 75%), good (50-70%), moderate (25-49%), and weak (less than 25%). The follow up of the treated patients was done at 2 weeks, 3 and 6 months. In patients with pain duration up to 3 months, the improvement was excellent in n=32 (58.18%) after 2 weeks, after 3 months n=41 (74.55%) and after 6 months n=41 (74.55%). This stands in contrast to patients with pain over 1 year. The percentage of improvement after 6 months, post-intervention, was highest in patients without nerve root compression (86.25±19.2),and the highest improvement after 6 months was in patients with localization of pain at the L4-L5 level (69.69±29.7), the greatest improvement after six months was in patients with extraforaminal hernia (62.82±34.3), and the lowest in patients with central stenosis (40.21±30.7).Our study results suggest that the shorter a pain duration, low-grade root compression, injection level and type of herniation area predictor the more favourable response patients have to transforaminal epidural steroid injection in patients with sciatica.

Effectiveness of Epidural Steroid Injection Depending on Discoradicular Contact: A Prospective Randomized Trial

Lumbar radicular pain is a major public health and economic problem. It is among the most common reasons for professional disability. The most common cause of lumbar radicular pain is intervertebral disc herniation, which results from degenerative disc changes. The dominant pain mechanisms are direct pressure of the hernia on the nerve root and the local inflammatory process triggered by intervertebral disc herniation. Treatment of lumbar radicular pain includes conservative, minimally invasive, and surgical treatment. The number of minimally invasive procedures is constantly increasing, and among these methods is epidural administration of steroids and local anesthetic through a transforaminal approach (ESI TF). The aim of this research was to examine the effectiveness of ESI TF as measured by a visual analog scale (VAS) and the Oswestry Disability Index (ODI), depending on whether there is contact between the herniated intervertebral disc and the nerve root. In both groups of participants, there was a significant reduction in pain intensity, but there was no significant difference between the groups. In the group with disc herniation and nerve root contact, the only significant reduction was in pain intensity (p < 0.001). There were no significant differences in measurements in other domains of the ODI. In the group without disc herniation and nerve contact, there was a significant difference in all domains except weight lifting. In the group without contact, there was significant improvement after 1 month (p = 0.001) and 3 months (p < 0.001) according to the ODI, while there was no significant improvement in the group with contact. In addition, there were no significant differences in the distribution of participants based on the ODI and whether disc herniation and nerve contact was present. The results suggest that transforaminal epidural administration of steroids is a clinically effective method for treating lumbar radicular pain caused by intervertebral disc herniation in people with and without nerve root contact, without significant differences.

The Role of Diagnostic Injections in Spinal Disorders: A Narrative Review

Neck and back pain is increasingly prevalent, and has increased exponentially in recent years. As more resources are dedicated to the diagnosis of pain conditions, it is increasingly important that the diagnostic techniques used are as precise and accurate as possible. Traditional diagnostic methods rely heavily upon patient history and physical examination to determine the most appropriate treatments and/or imaging studies. Though traditional means of diagnosis remain a necessity, in many cases, correlation with positive or negative responses to injections may further enhance diagnostic specificity, and improve outcomes by preventing unnecessary treatments or surgeries. This narrative review aims to present the most recent literature describing the diagnostic validity of precision injections, as well as their impact on surgical planning and outcomes. Diagnostic injections are discussed in terms of facet arthropathy, lumbar radiculopathy, discogenic pain and discography, and sacroiliac joint dysfunction. There is a growing body of evidence supporting the use of diagnostic local anesthetic injections or nerve blocks to aid in diagnosis. Spinal injections add valuable objective information that can potentially improve diagnostic precision, guide treatment strategies, and aid in patient selection for invasive surgical interventions.

Observer agreement in the choice of lumbar spine injection for pain management

BACKGROUND AND PURPOSE

Lumbar spine MRI can help guide the choice of corticosteroid injection in pain management. We investigated whether patient-reported symptom information from a questionnaire could improve agreement in the choice of type, level, and side of injection.

MATERIALS AND METHODS

In this prospective observational study, 120 patients (median age 64, 70 men) were recruited from patients referred for pain management. After informed consent, they completed electronic questionnaires that obtained symptom information for later use during MRI reviews. In 3 research arms, 6 radiologists chose injections that would ideally deliver corticosteroid to the presumed sources of pain in (1) MRI studies reviewed with symptom information from questionnaires, (2) MRI studies reviewed without symptom information, and (3) MRI reports. Blinded to questionnaire results, radiologists providing clinical care and interviewing patients chose ideal therapeutic injections to establish reference standards. Injections were categorized by type, level, and side and compared using percent agreement and kappa statistics. Interreading agreement was analyzed.

RESULTS

Compared to the reference standard, kappa agreements for injection types, levels, and sides were almost perfect when MRIs were reviewed knowing symptoms (0.85-0.93), fair without symptoms (0.23-0.35) (all P < .001) and fair in MRI reports (0.24-0.36) (all P < .001). Interreading kappa agreements were almost perfect knowing symptoms (0.82-0.90), but only moderate without symptoms (0.42-0.49) (all P < .001).

CONCLUSIONS

Radiologists reviewing lumbar spine MRI converged on the type, level, and side of ideal therapeutic injection whether they obtained symptom information from direct patient interview or electronic questionnaire. Observer agreement was significantly lower without symptom information.

Spinal nerve signal intensity on Dixon T2-weighted water-only sequence: an important outcome predictor after lumbar transforaminal epidural injection

OBJECTIVES

To evaluate the role of Dixon T2-weighted water-fat separation technique in predicting the outcome of lumbar transforaminal epidural injections (TFESIs).

METHODS

Patients who underwent TFESI of a single spinal nerve within 3 months after magnetic resonance imaging (MRI) exam between August 2018 and April 2020 were identified. The patients were classified into positive or negative outcome groups based on the response to the TFESI procedure. Two musculoskeletal radiologists measured the signal intensity of the injected side spinal nerves, contralateral side spinal nerves, and subcutaneous fat on axial Dixon T2-weighted water-only images, and the diameter of spinal nerve on axial Dixon T2-weighted in-phase images of the pre-procedural MRI. The measured values of the injected side spinal nerves were compared between the two groups and with the contralateral side spinal nerve.

RESULTS

A total of 94 patients were included, 76 in the positive outcome group and 18 in the negative outcome group. The mean signal intensity and the nerve-to-fat signal ratio of the injected side spinal nerve were significantly higher in the positive outcome group than in the negative outcome group (793.78 vs. 679.19, p = 0.016; 4.21 vs. 3.28, p = 0.003). In the positive outcome group, the diameter of the spinal nerve was significantly higher on the injected side than on the contralateral side (6.91 mm vs. 6.37 mm, p = 0.016).

CONCLUSIONS

The mean signal intensity and the nerve-to-fat signal ratio of the spinal nerve on axial Dixon T2-weighted water-only images can help predict patient response to the TFESI.

KEY POINTS

• Applying the Dixon technique to lumbar spine MRI can help predict patient response to the TFESI procedure. • An increased nerve-to-fat signal ratio and mean spinal nerve signal intensity on axial Dixon T2-weighted water-only images predicted favorable TFESI outcomes.

Predictive factors for treatment success of transforaminal epidural steroid injection in lumbar disc herniation-induced sciatica

Background/aim

The aim of this study was to identify predictive factors for treatment success in transforaminal epidural steroid injection in patients with lumbar disc herniation-induced sciatica.

Materials and methods

A total of 219 patients who were diagnosed with unilateral sciatica and underwent transforaminal epidural steroid injections at the level of L4-5, L5-S1, or S1 neural foramina between March 2016 and May 2018 were retrospectively analyzed. The presence of transitional vertebrae and the grade of nerve root compression were evaluated by a radiologist. Data including age, sex, body mass index, duration of symptoms, injection levels, and pain scores were recorded. Pain scores were evaluated using the numerical rating scale. Treatment success was defined as a ≥50% decrease in pain scores at 3 months.

Results

The study included 118 female and 101 male patients with a mean age of 43.65 ± 12.18 years. The mean duration of symptoms was 25.64 ± 2.17 weeks. Although the duration of symptoms was longer in patients for whom treatment failed, it did not reach statistical significance. Decreased pain scores at 1 h had a significant effect on treatment success (p = 0.012, odds ratio (OR): 1.015, 95% confidence interval (CI), 1.003–1.026).

Conclusions

Our study results suggest that a decreased pain score at 1 h is a predictor for a favorable three-month response to transforaminal epidural steroid injection in patients with lumbar disc herniation-induced sciatica.

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

OBJECTIVE

Lumbar radicular Syndrome (LRS) is a common spinal pathology and is attributed to complex interplay of mechanical, inflammatory and immunological processes. Epidural injection of steroids has a significant therapeutic role in mitigating the inflammatory component of LRS. Trans-foraminal approach under image guidance enables a targeted drug delivery. The current narrative review discusses the various aspects related to lumbar trans-foraminal epidural injection of steroid (LTFIS).

METHODS

An elaborate search on PubMed, Google and Medline databases was made using keywords "lumbar selective nerve root block", "lumbar trans-foraminal epidural steroid injection", "selective nerve root block in lumbar disc prolapse", "trans-foraminal epidural steroid injection in lumbar prolapse", "selective nerve root block in lumbar radiculopathy", and "trans-foraminal epidural steroid injection in lumbar radiculopathy" The articles were selected based on specific inclusion criteria.

RESULTS

Our search identified 539 articles. All articles discussing alternate procedures, LTFIS in other pathologies, diagnostic roles of LTFIS, not pertaining to concerned questions, in non-English language and duplicate articles were excluded. Review articles, randomised controlled trials or level 1 studies were given preference. Overall, 108 articles were included. Being a focussed narrative review, further screening [Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) or Methodological Index for non-randomized studies (MINORS) criteria] was not performed to select articles. Based on the evidence, LTFIS is an effective and useful treatment modality. It is offered to patients with lumbar disc herniation (LDH) presenting with persistent, unilateral, radiculopathy after a course of conservative measures for around 6 weeks' duration. It has been reported to yield better results than caudal or inter-laminar epidural injections. The anti-inflammatory and nociceptive signal stabilization actions of steroids, as well as mechanical effects of washout of inflammatory mediators and neural lysis contribute to its efficacy. The three different approaches include sub-pedicular, retro-neural and retro-discal. The procedure is performed under image guidance using a water-soluble contrast under fluoroscopy. The four described radiculogram patterns include "arm", "arrow", "linear" and "splash". Computerised tomography, ultrasonography and magnetic resonance imaging are other modalities, which may be helpful in performing LTFIS. The use of particulate versus non-particulate steroids is controversial.

CONCLUSION

The overall success rate of SNRB is reported to be 76-88%. The majority of benefits are observed during immediate and early post-injection period. Clinical factors including duration and severity of symptoms, and radiological factors like presence of osteophytes, location, size and type of disc prolapse influence outcomes. The radiculogram "splash" pattern is associated with poor outcomes.