Ultrasound-guided Pararadicular Injection in the Lumbar Spine: A Comparative Study of the Paramedian Sagittal and Paramedian Sagittal Oblique Approaches

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.

Ultrasound-guided versus fluoroscopy-guided lumbar selective nerve root block: a retrospective comparative study

The purpose of this study is to compare the accuracy and effectiveness of ultrasound-guided and fluoroscopy-guided lumbar selective nerve root block (SNRB), and to explore the feasibility of ultrasound-guided methods. This retrospective study included patients with lumbar radicular pain who underwent ultrasound-guided and fluoroscopy-guided selective nerve root block at Honghui Hospital Affiliated to Xi'an Jiaotong University from August 2020 to August 2022. Patients were divided into U-SNRB group and F-SNRB group according to ultrasound-guided or fluoroscopy-guided selective nerve root block. There were 43 patients in U-SNRB group and 20 patients in F-SNRB group. The pain visual analogue scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores, related indexes and complications were recorded and compared between the two groups before, 30 min, 1 month and 6 months after block. To evaluate the feasibility, accuracy and effectiveness of ultrasound-guided selective nerve root block. There were no complications in the process of selective nerve root block in both groups. The operating time and the times of closing needle angle adjustment in U-SNRB group were better than those in F-SNRB group, and the difference was statistically significant (P < 0.05). The VAS score and JOA score of patients in the two groups were significantly improved 30 min after block, 1 month and 6 months after block, and the difference was statistically significant (P < 0.05). There was no significant difference between the two groups (P > 0.05). The accuracy of ultrasound-guided selective nerve root block and the degree of pain relief of patients were similar to those of fluoroscopy guidance, but the operation time and needle angle adjustment times were significantly less than that of fluoroscopy, and could effectively reduce radiation exposure. Therefore, it can be used as a better way to guide for choice.

Accuracy of Ultrasound-Guided Needle Placement on the L5 Lumbar Nerve Root: A Cadaveric Study

OBJECTIVES

The aims of the study are to analyze and describe the accuracy of an ultrasound-guided approach to target the L5 root in cadaveric specimens and evaluate whether gender differences exist.

DESIGN

A cross-anatomical study on 40 cadaver L5 nerve roots was performed. A needle was introduced until contacting the L5 nerve root using ultrasound guidance. After that, specimens were frozen and studied by a cross-anatomical view to see the needle's path. The angulation, length, distance from the vertebral spine, the relevant ultrasound anatomical references, and the accuracy of the procedure were evaluated.

RESULTS

The needle tip reached the L5 root at a 72.5% rate. The mean angulation degrees of the needle relative to the skin surface were 75.53 ± 10.17 degrees, the length of the needle inserted was 5.83 ± 0.82 cm, and the distance from the vertebral spine to the point of entry of the needle was 5.39 ± 1.44 cm.

CONCLUSIONS

An ultrasound-guided technique can potentially be an accurate technique to perform invasive procedures on the L5 root. There were statistically significant differences between males and females in the length of the needle introduced. If the L5 root is not clearly visualized, ultrasound will not be the technique of choice.

Ultrasonographic Imaging Protocol and Sonoanatomy of the Lumbar Spine in Healthy Dogs

Ultrasound is an imaging technique commonly used in veterinary medicine. Ultrasound devices are widely available, their means of examination are relatively short and cheap, and they do not generate ionizing radiation. In addition, ultrasound generally does not need to be performed under general anesthesia. This study was performed on 23 canine cadavers with full clinical histories and with no confirmed pathological changes in the spine region. The imaging modalities were established in dogs in lateral recumbency, with the selected side being the uppermost angle, in a neutral position. All dogs were examined in the transverse and longitudinal planes. Sacral crest, intertransverse ligament, vertebral canal floor, vertebral body, and intervertebral discs were only visible in the longitudinal plane. Vertebral arch, supraspinal ligament, dorsal wall of the vertebral canal and muscles were visualized only in the transverse plane. This article provides a brief and relatively easy-to-perform protocol for ultrasound imaging of the lumbar spine of dogs. In addition, it presents a detailed description of the sonoanatomy of the area under investigation.

Ultrasound and nerve stimulator guidance lumbar transforaminal epidural block for the treatment of patients with lumbosacral radicular pain

Transforaminal epidural block (TEB) is a widely accepted technique and minimally invasive procedure for the treatment of lumbosacral radicular pain. This study aimed to evaluate the accuracy, efficacy, and safety of ultrasound and nerve stimulator guidance lumbar transforaminal epidural block (UNTEB) for the patients with unilateral lower lumbar radicular pain. The accuracy of this method was evaluated by fluoroscopy. Using UNTEB via axial and the in-plane approach technique was performed in 42 segments of 25 patients who presented with lumbosacral radicular pain to lower extremities. The contrast medium was injected to evaluate the needle tip at the intervertebral foramen under fluoroscopic guidance. The numerical rating scale was used to assess pain before and after treatment. The success ratio of UNTEB in L3/L4 level was 100%, in L4/L5 was 95.4% and in L5/S1 was 100%. The numerical rating scale (NRS) for lumbosacral radicular pain improved from a mean from 7.8 to 2.8 1 day after procedure (p = 0.01) and from a mean from 7.8 to 2.4 1 week after UNTEB (p = 0.01). None of our subjects experienced any complications during and after the procedure. UNTEB with fluoroscopic validation is an accurate, effective, and safe method for short-term pain relief of the patients with unilateral lumbosacral radicular pain.

Ultrasound-Guided Lumbar Transforaminal Epidural Injection: A Narrative Review

Transforaminal epidural steroid injection is often administered to patients with radiculopathy under fluoroscopic guidance, although it has disadvantages of radiation hazards and requirement of a special area to perform the block. To avoid these disadvantages, ultrasound-guided transforaminal injection (USTFI) has recently been described and is continually developed. This review article describes the indexed articles published on USTFI and ultrasound-guided selective nerve block (SNRB) to evaluate current evidence on best approach to perform the block. Through literature search, eight articles and one case report on USTFI and five articles on ultrasound-guided SNRB were found. Most of the studies have utilized parasagittal orientation of curvilinear probe to perform the block. Nevertheless, with the present literature, it is difficult to come to any conclusion. Further studies with larger sample size and description of dye spread patterns are recommended to come to a more definite conclusion.

Abdominal girth has a strong correlation with actual and ultrasound estimated epidural depth

Background/aim

This study aimed to assess the correlations of actual epidural depth (ND) and ultrasound estimated epidural depth in the paramedian sagittal oblique plane (ED/PSO) and transverse median plane (ED/TM) with the abdominal girth (AG), body mass index (BMI), and weight of patients.

Materials and methods

One hundred and thirty patients of either sex scheduled for unilateral inguinal hernia repair were enrolled. ED/PSO and ED/TM were assessed with a 2–5 MHz curved array probe at the L3–4 intervertebral space. The epidural needle was marked with a sterile marker upon locating the epidural space. The ND was assessed by measuring the distance from the sterile marker to the tip of the epidural needle with a linear scale. Anthropometric measures of the patients were recorded.

Results

ED/PSO was 49.6 ± 7.9 mm, ED/TM was 49.5 ± 7.9 mm, and ND was 50.0 ± 8.0 mm. AG was 99.8 ± 12.9 cm. The Pearson correlation coefficient between ND and ED/PSO was 0.997 and with ED/TM was 0.996 (P < 0.001 for both). Pearson correlation coefficients for ND with AG, BMI, and weight were 0.757, 0.547, and 0.638, respectively (P < 0.001 for all).

Conclusion

AG, weight, and BMI have strong correlations with ND.

Ultrasound-Assisted Versus Fluoroscopic-Guided Lumbar Sympathetic Ganglion Block: A Prospective and Randomized Study

BACKGROUND

Fluoroscopy (FL)-guided lumbar sympathetic ganglion block (LSGB) is widely performed to diagnose and manage various diseases associated with sympathetically maintained pain. Recently, numerous ultrasound (US)-assisted procedures in pain medicine have been attempted, showing an advantage of low radiation exposure. This randomized, prospective trial compared the procedural outcomes and complications between FL-guided and US-assisted LSGBs.

METHODS

Fifty LSGBs were randomly divided into 2 groups: FL-guided (FL group) or US-assisted (US group) LSGB group. Both groups received FL-guided or US-assisted LSGB with 10 mL of 0.25% levobupivacaine. The primary end point was the total procedure time. Secondary outcomes were success rate, imaging time, onset time (based on temperature rise), dosage of radiation exposure, other procedure-related outcomes, and complications.

RESULTS

Total procedure time and success rate were not statistically different between the 2 groups, whereas imaging time of the US group was longer than that of the FL group (P = .012). The onset time was faster in the US group (P = .019), and bone touching during the procedure was less frequent in the US group (P = .001). Moreover, radiation exposure was significantly lower in the US group than in the FL group (P < .001). No serious complications were reported in all patients.

CONCLUSIONS

US-assisted LSGB appears to be a feasible method with the added benefit of lower radiation exposure. In our study, we did not find an advantage of US-assisted LSGB over FL-guided LSGB in terms of performance time.

Visualization of Needle-Tip Localization by Ultrasound Guidance with Contrast Bubble in Lumbar Selective Nerve Root Block: Clinical Pilot Study

BACKGROUND

Epidural steroid injection for low back and leg pain has been shown to result in a positive clinical outcome. Lumbosacral selective nerve root block (SNRB) via a transforaminal approach is commonly performed under fluoroscopic guidance. However, ultrasound guidance is an alternative to overcome the radiologic disadvantages. This study examined the accuracy of needle-tip localization under ultrasound guidance with a contrast bubble, compared with fluoroscopic guidance.

OBJECTIVE

The primary objectives were to envisage the needle-tip localization with an air bubble by ultrasound and also to determine the accuracy of needle-tip location in transforaminal lumbar SNRB for low back and leg pain patients who were not surgical candidates.

METHODS

A prospective study of 30 SNRBs was conducted. An air bubble was produced and was used to envisage the needle-tip location under ultrasound guidance. Finally, the needle tip was confirmed by fluoroscopy. The accuracy of needle-tip location was statistically analyzed.

RESULTS

Twenty-four SNRBs were performed at L4-5 and 6 SNRBs at L3-4. The accuracy of needle-tip localization was 80%.

CONCLUSION

In order to avoid radiation exposure during the SNRB procedure, ultrasound guidance might be an alternative. Despite being accepted practice, there is a steep learning curve involved in the use of ultrasound guidance for lumbar SNRB, and proper training is crucial. A contrast bubble is a prospective enhancement for better visualization of ultrasound guidance.

Ultrasonography-Guided Lumbar Periradicular Injections for Unilateral Radicular Pain

Objective. The aim of this study was to compare the accuracy and efficacy of sonographically guided lumbar periradicular injections through in-plane or out-of-plane approach techniques for patients with unilateral lower lumbar radicular pain. The feasibility and accuracy of these techniques were studied by means of computed tomography (CT). Methods. A total of 46 patients with chronic unilateral lumbar radicular pain were recruited and randomly assigned to either the in-plane or out-of-plane injection group. A mixture of 3 mL 1% lidocaine and 7 mg betamethasone was injected. The visual analog scale (VAS) was used to assess pain before and after treatment. Results. The pain intensity, as measured by VAS, significantly decreased in both in-plane and out-of-plane injection groups. Conclusions. The sonographically guided periradicular injections are feasible and effective in treating lumbar unilateral radicular pain.

Ultrasound indications for chronic pain management: an update on the most recent evidence

PURPOSE OF REVIEW

The ability of ultrasound to provide detailed anatomic visualization while avoiding radiation exposure continues to make it an appealing tool for many practitioners of chronic pain management. This review will present the most recent evidence regarding the use of ultrasound-guidance for the performance of interventional procedures in the treatment of chronic pain.

RECENT FINDINGS

For a variety of different procedures, studies continue to compare ultrasound-guided techniques to commonly used fluoroscopic or landmark-based techniques. Small, randomized controlled trials are beginning to demonstrate that ultrasound-guided approaches to interventional pain procedures can be as well tolerated and effective as the traditionally used techniques, while providing some potential advantages in terms of decreased radiation exposure, avoidance of vascular structures, and in some cases, improved efficiency and decreased rates of adverse effects.

SUMMARY

Despite continued interest in ultrasound-guided techniques for chronic pain management procedures, the evidence is still limited mainly to small, randomized trials and case series. For some procedures, such as stellate ganglion block and peripheral joint injections, recent evidence appears to be tilting in favor of ultrasound-guidance as the preferred technique, though fluoroscopy continues to be a much more reliable method for detection of intravascular uptake of injectate.