Selective Nerve Root Block Research Articles

Driving Safety after Spinal Surgery: A Systematic Review.

This study aimed to assess driving reaction times (DRTs) after spinal surgery to establish a timeframe for safe resumption of driving by the patient postoperatively. The MEDLINE and Google Scholar databases were analyzed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) Statement for clinical studies that investigated changes in DRTs following cervical and lumbar spinal surgery. Changes in DRTs and patients' clinical presentation, pathology, anatomical level affected, number of spinal levels involved, type of intervention, pain level, and driving skills were assessed. The literature search identified 12 studies that investigated postoperative DRTs. Six studies met the inclusion criteria; five studies assessed changes in DRT after lumbar spine surgery and two studies after cervical spina surgery. The spinal procedures were selective nerve root block, anterior cervical discectomy and fusion, and lumbar fusion and/ordecompression. DRTs exhibited variable responses to spinal surgery and depended on the patients' clinical presentation, spinal level involved, and type of procedure performed. The evidence regarding the patients' ability to resume safe driving after spinal surgery is scarce. Normalization of DRT or a return of DRT to pre-spinal intervention level is a widely accepted indicator for safe driving, with variable levels of statistical significance owing to multiple confounding factors. Considerations of the type of spinal intervention, pain level, opioid consumption, and cognitive function should be factored in the assessment of a patient's ability to safely resume driving.

The Usefulness of Selective Nerve Root Block for Failed Back Surgery Syndrome

Purpose: To retrospectively evaluate the improvement of symptoms and diagnosis using selective nerve root block (SNRB) for radiating pain after spine surgery. Materials and Methods: From October 2012 to October 2013, 112 patients with failed back surgery syndrome (41 male and 71 female, with the mean age of 62.4 years and range of 35 to 78 years), who were admitted and underwent SNRB, were included. All patients were followed-up for more than 12 months. Three groups were classified: Group 1 included patients with no improvement or aggravation of symptoms, group 2 included those with improvement of radiating pain, and group 3 included those with recurrence of radiating. Results: Among the 112 patients, there were 15 patients in group 1, 59 patients in group 2, and 38 patients in group 3. Laminectomy was the highest surgical procedure, inducing failed back surgery syndrome. In group 2, the occurrence of failed back surgery syndrome was higher in case that radiating pain was complained more than 1 year before the first surgery. There is statistically significant symptom improvement in accordance with the visual analogue scale and Korean version of Oswestry disability index on every group after SNRB (p＜0.05). Conclusion: It is considered that SNRB is expected to improve the symptoms and to find the cause of symptoms as a diagnostic value even after spine surgery.

Ultrasonography Evaluation of Vulnerable Vessels Around Cervical Nerve Roots During Selective Cervical Nerve Root Block.

ObjectiveTo evaluate the prevalence of vulnerable blood vessels around cervical nerve roots before cervical nerve root block in the clinical setting.MethodsThis retrospective study included 74 patients with cervical radiculopathy who received an ultrasonography-guided nerve block at an outpatient clinic from July 2012 to July 2014. Before actual injection of the steroid was performed, we evaluated the vulnerable blood vessels around each C5, C6, and C7 nerve root of each patient's painful side, with Doppler ultrasound.ResultsOut of 74 cases, the C5 level had 2 blood vessels (2.7%), the C6 level had 4 blood vessels (5.45%), and the C7 level had 6 blood vessels (8.11%) close to each targeted nerve root. Moreover, the C5 level had 2 blood vessels (2.7%), the C6 level 5 blood vessels (6.75%), and the C7 level had 4 blood vessels (5.45%) at the site of an imaginary needle's projected pathway to the targeted nerve root, as revealed by axial transverse ultrasound imaging with color Doppler imaging. In total, the C5 level had 4 blood vessels (5.45%), the C6 level 9 blood vessels (12.16%), and the C7 level 10 had blood vessels (13.51%) either at the targeted nerve root or at the site of the imaginary needle's projected pathway to the targeted nerve root. There was an unneglectable prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of the needle' projected pathway to the nerve root. Also, it shows a higher prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of an imaginary needle's projected pathway to the nerve root as the spinal nerve root level gets lower.ConclusionTo prevent unexpected critical complications involving vulnerable blood vessel injury during cervical nerve root block, it is recommended to routinely evaluate for the presence of vulnerable blood vessels around each cervical nerve root using Doppler ultrasound imaging before the cervical nerve root block, especially for the lower cervical nerve root level.

Short-Term Effects of Selective Nerve Root Block in Spinal Stenosis Patients According to Spinal Canal Dimensions

Short-Term Effects of Selective Nerve Root Block in Spinal Stenosis Patients According to Spinal Canal Dimensions

Short-Term Effects of Selective Nerve Root Block in Spinal Stenosis Patients According to Spinal Canal Dimensions

Short-Term Effects of Selective Nerve Root Block in Spinal Stenosis Patients According to Spinal Canal Dimensions

Effectiveness of Selective Nerve Root Block for the Treatment of Single-Segment Lumbar Spinal Stenosis and Disc Herniation

Effectiveness of Selective Nerve Root Block for the Treatment of Single-Segment Lumbar Spinal Stenosis and Disc Herniation

Effectiveness of Selective Nerve Root Block for the Treatment of Single-Segment Lumbar Spinal Stenosis and Disc Herniation

Effectiveness of Selective Nerve Root Block for the Treatment of Single-Segment Lumbar Spinal Stenosis and Disc Herniation

요추부 선택적 신경근 차단술 이후 발생한 Wallenberg's Syndrome의 한방복합치료 1례

요추부 선택적 신경근 차단술 이후 발생한 Wallenberg's Syndrome의 한방복합치료 1례

A Randomized Comparative Study of Pulsed Radiofrequency Treatment With or Without Selective Nerve Root Block for Chronic Cervical Radicular Pain.

We demonstrated a combination of pulsed radiofrequency (PRF) and cervical nerve root block (CNRB) via a posterior approach was superior to a transforaminal epidural steroid injection through the anterolateral approach for cervical radicular pain in a previous study. This randomized trial was conducted to determine the comparative efficacy between CNRB, PRF, and CNRB + PRF for cervical radicular pain. A prospective and randomized design was used in this study. Sixty-two patients were randomized into three parallel groups: CNRB, PRF, or CNRB + PRF. Numeric Rating Scale (NRS) was used to measure pain intensity, and global perceived effect (GPE) was scored by the patient on a 7-point scale, ranging from much worse (-3), no change (0), to total improvement (+3). The outcomes were evaluated at 1 week, 1 month, 3 months, and 6 months. Side effects and complications were noted. The NRS was significantly reduced in all three groups 1 week after the treatments (P < 0.001), and the rates of positive GPE (+2 or +3) were not significantly different between the three groups. At 1, 3, and 6 months of follow-ups, the combined therapy achieved significantly lower NRS and higher GPE compared to CNRB or PRF alone group (P < 0.001). There were no significant differences between the CNRB and PRF groups (P > 0.05). No serious complications were observed in any of the patients. Combining CNRB and PRF appeared to be a safe and efficacious technique for cervical radicular pain. The combination therapy yielded better outcomes than either CNRB or PRF alone.

Diagnostic values of ProSet magnetic resonance coronal source imaging for detecting symptomatic lesion in multiple lumbar foraminal stenosis

ObjectiveThe aim of this study is to evaluate the values of ProSet magnetic resonance coronal source imaging (ProSet MR imaging) as a diagnostic tool for detecting symptomatic lesion in patients with multiple lumbar foraminal stenosis. Patients and methodsFrom January 2011 to June 2015, 46 patients with unilateral and single-level radiculopathy developed from foraminal stenosis were enrolled in the study. These diagnoses were confirmed with transforaminal selective nerve root block (SNRB) and electrophysiological testing, including electromyography and nerve conduction velocity (EMG/NCV) tests. The detection of symptomatic lesion among multiple lumbar foraminal stenosis was done by identification of spinal nerve swelling (NS) and/or running course abnormalities (RCA) observed on ProSet MR imaging. These results were compared with those from transforaminal SNRB testing and conventional MR imaging. Evaluations were performed blinded by two independent examiners. ResultsThe diagnostic accuracy rates of the two examiners were 84.7% and 82.6% with a 0.835 kappa coefficient. NS (80.4%) showed a higher diagnostic accuracy rate compared to RCA (69.6%) for detecting symptomatic lesion. The presence or absence of both NS and RCA has a stronger relationship with symptomatic or non-symptomatic lesion compared to the relationship of either alone (p=0.00). ConclusionProSet MR imaging is a simple and helpful method for providing additional diagnostic accuracy to detect symptomatic lesion in patients with multiple foraminal stenosis. NS representing chemical radiculitis was more reliable diagnostic factor of ProSet MR imaging.

Clinical usefulness and safety of selective lumbar nerve root blocks

Clinical usefulness and safety of selective lumbar nerve root blocks

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

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. 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. 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. 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. 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.

Predictive Factors for Successful Outcome of Pulsed Radiofrequency Treatment in Patients with Intractable Lumbosacral Radicular Pain

In a previous prospective study on pulsed radiofrequency (PRF) treatment adjacent to the lumbar dorsal root ganglion (DRG) for patients with chronic lumbosacral radicular pain, we reported success in 55.4% of the patients at 6 months. Identification of predictors for success after PRF may improve outcome. We assessed the predictors of PRF in patients with chronic intractable lumbosacral radicular pain. Patients with monosegmental chronic lumbosacral radicular pain of L5 or S1 first received a selective nerve root block at the corresponding level. Independent of the result of this block a PRF treatment at the same level was performed. At 6 weeks, 3 months, and 6 months after the procedure the outcome was evaluated. A positive diagnostic nerve root block and age ≥ 55 were predictive factors for successful outcome at 6 months, while disability was a negative predictor.The use of failed back surgery syndrome, gender, duration of pain, Numerical Rating Scale, level and side of treatment, DN4, and RAND-36 as predictors for success was not supported. Successful outcome after PRF adjacent to the DRG, in patients with intractable chronic lumbosacral radicular pain, is more likely in patients ≥ 55 years, with limited disability and after a positive diagnostic nerve root block. A combination of all these factors creates a fair predictive value (AUC: 0.73).

Significance of Coronal Proset Magnetic Resonance Imaging to Detect Hidden Zone of the Mid-Zone Stenosis in the Lumbar Spine and Morphometric Analysis of the Mid-Zone Stenosis.

Study DesignRetrospective exploratory imaging study.PurposeTo investigate the significance of the coronal magnetic resonance imaging (MRI) using Proset technique to detect the hidden zone in patients with mid-zone stenosis by comparing with conventional axial and sagittal MRI and to explore the morphologic characteristic patterns of the mid-zone stenosis.Overview of LiteratureDespite advancements in diagnostic modalities such as computed tomography and MRI, stenotic lesions under the pedicle and pars interarticularis, also called the mid-zone, are still difficult to definitely detect with the conventional axial and sagittal MRI due to its inherited anatomical peculiarity.MethodsOf 180 patients scheduled to undergo selective nerve root block, 20 patients with mid-zone stenosis were analyzed using MRI. Characteristic group patterns were also explored morphologically by comparing MRI views of each group after verifying statistical differences between them. Hierarchical cluster analysis was performed to classify morphological characteristic groups based on three-dimensional radiologic grade for stenosis at all three zones.ResultsAt the mid-zone, the stenosis of grade 2 or more was found in 14 cases in the coronal image,13 cases in the sagittal image, and 9 cases in the axial image (p<0.05). Especially, mid-zone stenosis was not detected in six of 20 cases at the axial images. At the entrance and exit-zone, coronal image was also associated with more accurate detection of hidden zone compared to other views such as axial and sagittal images. After repeated statistical verification, the morphological patterns of hidden zone were classified into 5 groups: 6 cases in group I; 1 case in group II; 4 cases in group III; 7 cases in group IV; and 2 cases in group V.ConclusionsCoronal MRI using the Proset technique more accurately detected hidden zone of the mid-zone stenosis compared to conventional axial and sagittal images.

Effectiveness of Selective Nerve Root Block on the Need for Surgical Treatment of Patients with Cervical Radicular Pain: A Minimum 5 Years Follow-Up

Effectiveness of Selective Nerve Root Block on the Need for Surgical Treatment of Patients with Cervical Radicular Pain: A Minimum 5 Years Follow-Up

The Outcomes of Selective Nerve Root Block for Disc Induced Lumbar Radiculopathy.

Introduction : Use of Selective Nerve Root Block (SNRB) in lumbar region to relieve radicular pain along the course of a particular nerve is being practiced in the recent past. We observed and tabulated therapeutic outcomes of this procedure in management of radiculopathy induced by a prolapsed disc affecting a particular lumbar nerve root.Methods : 40 patients with various grades of disc prolapse affecting a particular lumbar nerve root presenting with chronic radicular pain were identified irrespective of age and sex. All were injected with a combination of 40 mg of Methylprednisolone based suspension with local anaesthetic over the affected nerve root and results were analyzed.Results : Those graded mild had 4.3 months relief and those graded moderate had 2.5 months relief. Those with severe disc prolapse had no relief except for the immediate postprocedural relief. Only 20% patients had relief up to 6 months.Conclusion : Effect of SNRB is typically short acting in majority of patients and recurrence is expected. It creates a window period with reduced pain but of varied intervals depending on the pathology. It did not alter the prognosis in those with severe disease where surgery is well indicated.Level of Evidence – Level 4

Femoral Neurogram Before Transpsoas Spinal Access at L4–5 Intervertebral Disk Space

Observational study. To illustrate the variability of the course of the femoral nerve across the L4-5 disk space, and to present a novel application of transforaminal epidural steroid injections (TFESI) in the visualization of femoral nerve roots. A concern regarding the lateral retroperitoneal transpsoas approach is the proximity of the lumbar plexus. Current techniques of assessing the proximity of neural tissue to the L4-5 disk space have limited capabilities. A total of 100 patients were selected for L4-5 TFESI (L4 selective nerve root blocks) because of lumbar radiculopathy. L4 neurograms were obtained while performing L4-5 TFESI under flouroscopic guidance, using a retroneural technique. The course of the L4 root/femoral nerve was then evaluated under fluoroscopy in the anteroposterior and lateral planes. Images were then reviewed by a radiologist, physiatrist, and 2 orthopedic spine surgeons. Fluoroscopic evaluation revealed that the pattern of location of the femoral nerve was highly variable. In males, it was located 4.7% in zone 2, 32.5% in zone 3, 53.5% in zone 4, and 9.3% in zone P. In female patients, it was located 7.0% in zone 2, 14% in zone 3, 54.4% in zone 4, and 24.6% in zone P. An L4 neurogram will provide an accurate trajectory of L4 root/femoral nerve as it crosses the L4-5 intervertebral disk space. An accurate assessment is essential to help minimize the increasing frequency of thigh pain, paresthesias, and weakness associated with the lateral access to the L4-5 intervertebral disk space. Femoral nerves that fall within zones 2 and 3 will require more manipulation during retraction and may be better suited with a different surgical approach.

Correlation of Foraminal Area and Response to Cervical Nerve Root Injections.

Introduction: Patients with age-related degenerative changes in the cervical spine leading to cervical spondylosis may be symptomatic or asymptomatic. Older patients with radicular pain tend to have a better response to epidural steroid injections, but it is often difficult to predict which patients will have a positive response to selective nerve root block (SNRB). We analyzed whether the cervical neuroforaminal area measured on MRI predicts immediate therapeutic responses to SNRB in patients who have cervical radiculopathy.Methods: We retrospectively reviewed all patients who had cervical SNRBs treated at a single tertiary referral center. We recorded patient demographics, the neuroforaminal area of the symptomatic and contralateral sides, Visual Analog Scale (VAS) score pre- and post-injection, history of previous cervical surgery, comorbidities, and history of tobacco use.Results: Sixty-four patients with symptoms of cervical radiculopathy treated with neuroforaminal nerve root injections had appropriate imaging and VAS scores recorded. The average foraminal area of the symptomatic side before treatment was significantly smaller than the contralateral asymptomatic neuroforamen (p<0.0001). Those patients with the smallest neuroforamen had a positive response to SNRB. Diabetes and tobacco use did not influence patient response to treatment.Conclusions: Measurement of neuroforaminal areas on MRI may represent a useful pre-procedural technique to predict which patients with symptoms of cervical radiculopathy secondary to foraminal stenosis are likely to respond to selective nerve root injections. The predictive ability appears to be limited to those patients with severe stenosis and was less useful in those patients with moderate or mild stenosis.

A posterior approach to cervical nerve root block and pulsed radiofrequency treatment for cervical radicular pain: a retrospective study

BackgroundCatastrophic complications have been reported for selective cervical nerve root block (SCNRB) or pulsed radiofrequency (PRF) via an anterolateral transforaminal approach. A posterior approach to these procedures under computed tomography guidance has been reported. Here, we report the clinical outcomes of 42 patients with chronic cervical radicular pain (CCRP) treated with a combination of SCNRB and PRF through a posterior approach under fluoroscopy guidance. MethodsWe retrospectively reviewed the clinical outcomes of 42 consecutive patients with CCRP who received a combination of SCNRB and PRF through a posterior approach under fluoroscopy guidance. The thresholds of electrical stimulation and imaging of the nerve roots after contrast injection were used to evaluate the accuracy of needle placement. The numeric rating scale was used to measure the pain and numbness levels as primary clinical outcomes, which were evaluate in scheduled follow-up visits of up to 3 months. ResultsA total of 53 procedures were performed on 42 patients at the levels of C5-C8. All patients reported concordant paresthesia in response to electrical stimulation. The average sensory and motor thresholds of stimulation were 0.28 ± 0.14 and 0.36 ± 0.14 V, respectively. Injection of nonionic contrast resulted in excellent spread along the target nerve root in large majority of the procedures. The numeric rating scale scores for both pain and numbness improved significantly at 1 day, 1 week, and 1 and 3 months after the treatment. No serious adverse effects were observed in any of the patients. ConclusionsThe posterior approach to combined SCNRB and PRF under fluoroscopy guidance appears to be safe and efficacious in the management of CCRP.

Long-Term Effect of Selective Nerve Root Block in patients with Lumbar Stenosis

Introduction Low back pain with radiculopathy is a common problem encountered both by the young and the elderly. In the young, it may be caused by HNP and/or chemical irritation causing nerve impingement. In the elderly, it is usually caused by a degenerative process causing stenosis. One problem faced by the surgeon is when the patient has an equivocal presentation; wherein surgical outcome becomes unpredictable. The aim of our study was to show the long-term effect of selective nerve root block, using a combination of lidocaine and methylprednisolone, in patients suffering from low back pain with equivocal presentation caused by lumbar spinal stenosis. Materials and Method This has a prospective study design, SNRB was done in patients with equivocal symptoms. A total of 19 patients who satisfied the inclusion criteria were included in the study, informed consent was granted by all the participants. All the patients already underwent at least eight sessions of physical therapy and took oral analgesics with no relief of symptoms. SNRB was done in a sterile environment with the guidance of an image intensifier. A combination of 1 mL methylprednisolone and 1 mL of 2% lidocaine was injected after verification of the needle position in two planes was done. The procedure was completed with the patient awake to elicit sensory changes to confirm proper positioning of the needle. Close follow-up was done at 1 week, 3 weeks, 3 months, 6 months, 1 year, and 3 years post-SNRB. Results After 1 week, 17 patients reported resolution of symptoms. Immediate relief was observed in 15 patients after the injection. At 1 year, all 17 patients still reported no recurrence of pain. Three were lost to follow-up, failing to return for the 3rd year post-SNRB, decreasing the success rate at 3 years to 15 patients out of 19. The remaining two patients required repeat SNRB, with one of the two eventually requiring surgical decompression. Conclusion This study showed that the combination of methylprednisolone and lidocaine was able to provide pain relief in 89% of the participants at 1 year follow-up, and 74% at 3 years. SNRB may be used in treating patients with equivocal presentation, providing faster relief than other conservative management, and evading unnecessary surgery.