Cervical Selective Nerve Root Block Research Articles

Ultrasound-Guided Cervical Selective Nerve Root Block versus Fluoroscopy-Guided Interlaminar Epidural Injection for Cervical Radicular Pain: A Randomized, Prospective, Controlled Study.

Ultrasound (US)-guided cervical selective nerve root block (CSNRB) procedures are increasingly being performed as an alternative to conventional fluoroscopy (FL)-guided epidural injections for the treatment of cervical radicular pain. The aim of this study was to compare the effectiveness of US-guided CSNRB versus FL-guided interlaminar cervical epidural steroid injection (IL-CESI) for cervical radicular pain. A total of 60 patients with cervical radicular pain due to a single-level disc herniation were randomized into either the FL or US group. The numeric rating scale, Short Form-36, and neck disability index were evaluated before treatment at months 1, 3, and 6 after treatment. Procedure time, complications, pain medication consumption, and patient satisfaction were also recorded. Patients experienced significant improvement in pain, disability, and quality of life scores up to 6 months after the procedure (p < 0.001). Treatment success rate was achieved in 56.6% of the IL-CESI group and 50% of the CSNRB group without any significant difference between the study arms (p = 0.617). US-guided CSNRB was shown to be as effective as the FL-guided IL-CESI in the treatment of cervical radicular pain, in addition to the absence of radiation exposure and requiring less procedure time.

A New, Effective, Safe, and Accurate Method of Cervical Selective Nerve Root Block

Objective: Cervical selective nerve root block (SNRB) is an effective procedure that has long been performed for patients with radiating pain or paresthesia. However, there are several delicate structures around the cervical nerve root, damage to which could lead to irreversible neurovascular injury. Therefore, cervical SNRB requires a high skill level and extensive experience to execute it safely. To overcome these disadvantages, we used biplane computed tomography (CT)-guided fluoroscopy and a needle guidance program to achieve symptom improvement in a safer and shorter procedure. This study aimed to investigate the new method and report on its excellent clinical effects.Methods: A total of 57 patients who experienced radiating pain due to cervical spinal stenosis resulting from a herniated disc were enrolled. From September 2020 to September 2021 subjects underwent a biplane CT-guided fluoroscopic nerve block at an outpatient clinic. All procedures were performed by biplane CT-guided fluoroscopy. We analyzed treatment effects with a numerical rating scale (NRS) at 2 and 4 weeks after the procedure. Logistic regression was performed to reveal the significance of changes in NRS after the injection.Results: Pain improved in 56 of 57 patients (98%) after 2 and 4 weeks of follow-up compared to pre-injection pain. At the 2-week follow-up, the mean reduction based on NRS scores was 3.226 (2.782-3.674, 0; 95% confidence interval [CI], p &lt; 0.001) indicating a 48% decrease in pain scores compared with the initial NRS. The mean reduction in NRS 4 weeks after the procedure was 3.544 (3.090-3.998, 0; 95% CI, p &lt; 0.001) indicating a 52% reduction compared with the initial NRS. The average duration of the procedure was 4 minutes. Conclusion: We demonstrate a clinically effective, safe, and accurate method using a biplane CT-guided fluoroscopy and needle guide program. This new method can be an easy and relatively uncomplicated alternative to treatment for patients with cervical radiculopathy and provides safe and accurate targeting, making it easy for inexperienced surgeons.

Evaluating the Extent of Ultrasound-Guided Cervical Selective Nerve Root Block in the Lower Cervical Spine: Evidence Based on Computed Tomography Images.

To verify the injectate dispersal patterns (IDP) and therapeutic outcome of ultrasound-guided cervical selective nerve root block (UG-SCNRB) in treating cervical radiculopathy (CR). Overall, 18 CR patients were recruited to undergo UG-SCNRB in the CT room. Following placement of the puncture needle tip between the target nerve root and posterior tubercle, 3 mL of the drug was administered per root (0.33% lidocaine 0.5 mL + Compound betamethasone injection 0.5mL + methylcobalamin injection 1mL + iohexol 1mL). Subsequently, the IDP was assessed on postintervention CT scan images. In all, 18 participants were analyzed. We injected 21 target cervical nerve roots, namely, 1 C4 nerve, 9 C5 nerves, and 11 C6 nerves. Among the IDPs on postintervention CT scan images, two IDPs were most prevalent, namely, the contrast spread into the extraforaminal spaces (Zone I, the interscalene) in 100% (21/21) of cases, and the foraminal space spread (Zone II) in 61.90% (13/21) of cases. The injectate spread into the epidural spaces (Zone III) in only 2 out of 21 cases (9.52%). The pain relief was significantly improved two hours after surgery, compared to the preoperative VAS pain scores (2 hours, 1.39±0.50 vs VAS at baseline, P<0.01). The VAS pain scores during follow-up were significantly lower than preoperation (1 weeks, 1.94±0.54 vs VAS at baseline; 2 weeks, 2.61±0.70, P<0.01 vs VAS at baseline; 4 weeks, 2.67±0.59, P<0.01 vs VAS at baseline). We verified, via CT imaging, that the UG-SCNRB drug diffusion was within safe range (the injectate mainly spread to the extraforaminal spaces), and without any serious complications, such as, intravascular drug injection, extensive diffusion of the epidural space, and general spinal anesthesia.

Diagnosis and Treatment of Cervical Spondylotic Radiculopathy Using Selective Nerve Root Block (SNRB): Where are We Now?

Cervical spondylotic radiculopathy (CSR) is one of the most common degenerative diseases of the spine that is commonly treated with surgery. The primary goal of surgery is to relieve symptoms through decompression or relieving pressure on compressed cervical nerves. Nevertheless, cutaneous pain distribution is not always predictable, making accurate diagnosis challenging and increasing the likelihood of inadequate surgical outcomes. With the widespread application of minimally invasive surgical techniques, the requirement for precise preoperative localization of the affected segments has become critical, especially when treating patients with multi-segmental CSR. Recently, the preoperative use of a selective nerve root block (SNRB) to localize the specific nerve roots involved in CSR has increased. However, few reviews discuss the currently used block approaches, risk factors, and other aspects of concern voiced by surgeons carrying out SNRB. This review summarized the main cervical SNRB approaches currently used clinically and the relevant technical details. Methods that can be used to decrease risk during cervical SNRB procedures, including choice of steroids, vessel avoidance, guidance with radiographs or ultra-sound, contrast agent usage, and other concerns, also are discussed. We concluded that a comprehensive understanding of the current techniques used for cervical SNRB would allow surgeons to perform cervical SNRB more safely.

Risk Analysis of Needle Injury to the Long Thoracic Nerve during Ultrasound-Guided C7 Selective Nerve Root Block.

Background and Objectives: Ultrasound (US)-guided cervical selective nerve root block (SNRB) is a widely used treatment for upper limb radicular pain. The long thoracic nerve (LTN) passes through the middle scalene muscle (MSM) at the C7 level. The needle trajectory of US-guided C7 SNRB pierces the MSM, therefore indicating a high probability of injury to the LTN. We aimed to identify the LTN and to investigate the risk of needle injury to the nerve during US-guided C7 SNRB. Materials and Methods: This retrospective observational study included 30 patients who underwent US-guided SNRB at the C7 level in a university hospital. We measured the maximal cross-sectional diameter (MCSD) of the LTN and cross-sectional area (CSA) of the C7 nerve root and assessed the injury risk of LTN during US-guided C7 SNRB by simulating the trajectory of the needle in the ultrasound image. Results: The LTN was detectable in all the cases, located inside and outside the MSM in 19 (63.3%) and 11 (36.7%) of cases, respectively. The LTN’s mean MCSD was 2.10 mm (SD 0.13), and the C7 root’s CSA was 10.78 mm2 (SD 1.05). The LTN location was within the simulated risk zone in 86.7% (26/30) of cases. Conclusion: Our findings suggest a high potential for LTN injury during US-guided C7 SNRB. The clear visualization of LTNs in the US images implies that US guidance may help avoid nerve damage and make the procedure safer. When performing US-guided C7 SNRB, physicians should take into consideration the location of the LTN.

Persistent Hiccups after Cervical Selective Nerve Root Block

Persistent Hiccups after Cervical Selective Nerve Root Block

Counterpoint: Conventional Fluoroscopy-Guided Selective Cervical Nerve Root Block-A Safe, Effective, and Efficient Modality in the Hands of an Experienced Proceduralist.

The conventional fluoroscopy-guided (CF) selective cervical nerve root block (SCNRB) is being used commonly as a treatment for cervical radicular pain as well as a diagnostic tool. This study aimed to identify any major complications and determine the safety and clinical utility of CF-SCNRB performed in a university hospital and associated outpatient clinics. Two-hundred fifty-four conventional fluoroscopy-guided selective cervical nerve root blocks were retrospectively identified from 2011 to 2018 using a radiology report search tool. Each procedure was performed by an experienced neuroradiologist performing spinal injections on a full-time basis in clinical practice. A 10-point pain scale was used for pre- and postprocedural pain-level assessment. Successful conventional, fluoroscopy-guided, selective cervical nerve root block was defined as a patient-reported pain scale reduction of at least 50% and/or alleviation of numbness or paresthesia at ≥2 weeks postinjection. All clinically important immediate and delayed complications were also recorded. Two-hundred fifty-four conventional fluoroscopy-guided selective cervical nerve root blocks were performed via an anterolateral approach with an average fluoroscopy time of 24.3 seconds for all cases. There were no aborted procedures and no major or permanent complications. There were 14 minor complications; 12 of these were periprocedural and resolved by the 2-week follow-up visit. One-hundred eighty-five patients (75.2%) reported pain improvement of >50% from baseline at 15 minutes postinjection. Overall, 172 patients (67.7%) reported >50% pain scale reduction or alleviation from paresthesia at least 2 weeks postinjection. Conventional fluoroscopy-guided selective cervical nerve root block is an efficacious, efficient, and safe outpatient procedure when performed by a skilled and experienced proceduralist.

Ultrasound-guided Selective Cervical Nerve Root Block Plus Superficial Cervical Plexus Block for Minimally Invasive Parathyroidectomy.

Objective To explore the efficacy and safety of ultrasound-guided cervical root block (CRB) in patients undergoing minimally invasive parathyroidectomy (MIP).Methods We enrolled 35 patients with hyperparathyroidism undergoing MIP in Peking Union Medical College Hospital.C4-7 nerve roots were identified in ultrasound imaging by the shape of the transverse process.A 50 mm insulated needle was gently introduced by an in-plane approach toward the posterior edge of the nerve root located at the inside of the posterior tubercle.After careful aspiration,a total of 3-4 ml of a mixture of 0.5% ropivacaine and 1% lidocaine was slowly injected.The superficial block was administered at the midpoint of the posterior border of the sternocleidomastoid by injecting 5-6 ml of the same mixture.The patients were administrated with dexmedetomidine during the surgery.All patients were assessed for sensory following the procedure and for pain after the surgery.Results Totally 35 patients successfully received MIP under ultrasound-guided CRB plus superficial block.There was no conversion to general anesthesia,no toxic reaction of local anesthetics,and no intravertebral injection.Hoarseness occurred in 6 patients (17.1%) and Horner syndrome occurred in 3 patients (8.6%).The median cold sensory visual analogue scale score was 1.2 [0,5] points at 10 minutes after the procedure.Patient's satisfaction score was 9.5 points.Conclusion Ultrasound-guided CRB plus superficial block can achieve accurate and safe anesthesia,and it provides lasting analgesic effect during and after MIP.

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.

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.

Cervical nerve root blocks for chronic cervical radiculopathy - Does it influence surgical decision making?

Objective: It is often difficult to pinpoint the affected nerve root/roots from clinical symptoms and Magnetic Resonance Imaging (MRI) alone in patients with chronic cervical radiculopathy and multilevel degenerative changes. MRI often shows degenerativechanges at more than one level. Degenerative changes can occur in patients without symptoms and clinical diagnosis. Analysesof referred pain distribution from cervical nerve roots have shown only 50% correlation to the classical sensory dermatome. Surgical treatment of patients with cervical radiculopathy attributed to degenerative disease is associated with moderate outcomeresults. Our aim was to assess the diagnostic value of cervical selective nerve root blocks (SNRB) in our Trust in surgical decisionmaking. Methods: The data was collected retrospectively from electronic hospital records on CRIS, PACS and NOTIS on consecutivepatients who underwent cervical nerve root blocks for diagnostic purpose between 1st Jan 2011 and 31st December 2011. Results: Total of 50 patients had cervical SNRB for diagnostic reasons. It influenced surgical decision making in 84% (42) ofthese patients and not in 2% cases. 10% did not have any follow up after cervical SNRB. Decision in favour of surgery wasmade in 71.5% of these 42 patients. Conclusions: In chronic cervical brachialgia, cervical SNRB is extremely influential in surgical decision making, in bothwhether to operate and which levels scenario.

Optimal Needle Entry Angle for Cervical Transforaminal Epidural Injections

Background: Cervical epidural steroid injections can be performed through either interlaminar or transforaminal approaches, although the interlaminar approach is more frequently used, for cervical radicular pain as a result of cervical disc herniation or spinal stenosis. Cervical selective nerve root block (CSNRB) is an injection that uses a similar approach to that of cervical transforaminal epidural steroid injection (CTFESI) but CSNRB is mainly used for diagnostic injection, often with local anesthetic only. Objective: The aim of this study was to investigate an optimal needle entry angle for cervical transforaminal epidural steroid injection (CTFESI) or cervical selective nerve root block (CSNRB) using the fluoroscopically guided anterior oblique approach. The angle for optimal entry into the neuroforamen was measured at various vertebral levels using cross-sectional cervical spine computed tomography (CT) scans. Study Design: Retrospective case series analysis. Methods: From March 2009 to July 2012, consecutive patients with presumed discogenic neck pain underwent cervical post discography CT scans. The axial images of these CT scans were used to measure the optimal angle for needle entry into the neuroforamen. The angles were taken bilaterally at levels of C3-4, C4-5, C5-6, C6-7, and C7-T1. The average angle between the patient’s left and right side was calculated. A total of 190 patients were analyzed, including 73 men and 117 women, with ages ranging from 21 to 78 years old. Results: In both men and women, the mean optimal angle (in degrees) with standard deviation measured in the 190 patients at C3-4, C4-5, C5-6, C6-7, and C7-T1 were 48 ± 4, 49 ± 4, 49 ± 4, 49 ± 5, 48 ± 6, respectively. The 95% confidence interval for the true value of the parameter is within 39.84 to 57.56 degrees. Limitations: The data for the optimal needle entry angle for CTFESI has yet to be tested or confirmed in clinical studies. Conclusion: This is the first study investigating the optimal needle entry angle for performing CTFESIs or CSNRB. Based on a patient population of 190, the optimal entry angle using the anterior oblique approach appears to be between the range of 33 to 68 degrees with an average of slightly less than 50 degrees. Further research with angle of needle entry and/or initial fluoroscopic alignment of approximately 50 degrees in CTFESI or CSNRB is warranted to confirm the usefulness of these findings. Key words: Pain medicine, transforaminal, cervical, epidural, cervical selective nerve root block, cervical disc herniation, interlaminar, neck pain, vertebral artery, radiculomedullary artery

A Simple, 10-minute Procedure for Transforaminal Injection under Ultrasonic Guidance to Effect Cervical Selective Nerve Root Block

The aim is to provide a detailed procedure of a simple and 10-minute cervical nerve root block (CNRB) under ultrasonic guidance, and to report the clinical outcomes, disorders, and complications. Records of patients who had undergone CNRB, were reviewed under ultrasonic guidance at the hospital from 2010 through 2012. The procedure is described in detail. Arm and shoulder pain was evaluated by use of the visual analogue scale (VAS). Forty-three patients agreed to undergo CNRB under ultrasonic guidance. Nerve roots from C5 to C8 were affected in 41, and these nerve roots were readily distinguished. Two of the 43 participants did not receive injections because impediments in visualizing the affected nerve root. Of the 41 who received injections, radicular pain immediately disappeared in 39, who continued to feel pain relief 1 month later. However, pain recurred in 15 patients (38%), of whom 11 underwent cervical spine surgery. The rest of 24 patients felt sustained pain relief longer than 3 months after the injection, significantly. Although one patient had recurrent radicular pain 10 months later, the pain could be controlled by medication. At the final follow-up periods, 17.2 (10–24 months), the median VAS score of the patients, 23 (0 to 71 mm), was significantly improvement (P = 0.001) in comparison to before injection 88 (range; 56–100). No complications occurred. The cervical nerve root block under ultrasonic guidance simply, safely, and efficaciously decreased radicular pain for 17.2 months in 62% patients with intolerable radicular pain.

Ultrasound guided selective cervical nerve root block and superficial cervical plexus block for surgeries on the clavicle.

We report the anaesthetic management of two cases involving surgeries on the clavicle, performed under superficial cervical plexus block and selective C5 nerve root block under ultrasound (US) guidance, along with general anaesthesia. Regional analgesia for clavicular surgeries is challenging. Our patients also had significant comorbidities necessitating individualised approach. The first patient had a history of emphysema, obesity, and was allergic to morphine and hydromorphone. The second patient had clavicular arthritis and pain due to previous surgeries. He had a history of smoking, Stevens-Johnson syndrome, along with daily marijuana and prescription opioid use. Both patients had an effective regional block and required minimal supplementation of analgesia, both being discharged on the same day. Interscalene block with its associated risks and complications may not be suitable for every patient. This report highlights the importance of selective regional blockade and also the use of US guidance for an effective and safe block.

Laser-Guided Cervical Selective Nerve Root Block with the Dyna-CT: Initial Experience of Three-Dimensional Puncture Planning with an Ex-Vivo Model

BackgroundCervical selective nerve root block (CSNRB) is a well-established, minimally invasive procedure to treat radicular cervical pain. However, the procedure is technically challenging and might lead to major complications. The objective of this study was to evaluate the feasibility of a three-dimensional puncture planning and two-dimensional laser-guidance system for CSNRB in an ex-vivo model.MethodsDyna-CT of the cervical spine of an ex-vivo lamb model was performed with the Artis Zee® Ceiling (Siemens Medical Solutions, Erlangen, Germany) to acquire multiplanar reconstruction images. 15 cervical nerve root punctures were planned and conducted with the syngo iGuide® laser-guidance system. Needle tip location and contrast dye distribution were analyzed by two independent investigators. Procedural, planning, and fluoroscopic time, tract length, and dose area product (DAP) were acquired for each puncture.ResultsAll 15 punctures were rated as successful with 12 punctures on the first attempt. Total procedural time was approximately 5 minutes. Mean planning time for the puncture was 2.03 (±0.39) min. Mean puncture time was 2.16 (±0.32) min, while mean fluoroscopy time was 0.17 (±0.06) min. Mean tract length was 2.68 (±0.23) cm. Mean total DAP was 397.45 (±15.63) µGy m2.ConclusionCSNRB performed with Dyna-CT and the tested laser guidance system is feasible. 3D pre-puncture planning is easy and fast and the laser-guiding system ensures very accurate and intuitive puncture control.

Treatment Effects of Ultrasound Guide Selective Nerve Root Block for Lower Cervical Radicular Pain: A Retrospective Study of 1-Year Follow-up

ObjectiveTo compare the long-term effects and advantages of ultrasound (US)-guided selective cervical nerve root block with fluoroscopy (FL)-guided transforaminal block.MethodsFrom March 2009 to November 2012, 162 patients received steroid injections for lower cervical radicular pain. A total of 114 patients fulfilled the inclusion criteria. All procedures were performed by using US or FL. We compared the intravascular injections during the procedure with the effects and functional scales at 3, 6, and 12 months after the procedure between the two groups. Successful treatments occurred when patients obtained significant pain reliefs (as measured by >50% improvements in the verbal numerical scale [VNS] score and >40% improvements in the neck disability index [NDI] score) and reported a patient satisfaction score of 3 or 4 points at 12 months after the injection. Image analysis of intravascular injection and chart review were performed. Logistic regression was performed to reveal the correlations between successful treatments and variables (patient's age, gender, duration of the disease, cause, injection method, and radiologic finding).ResultsThe VNS and NDI improved 3 months after the injection and continued to improve until 12 months for both groups. But there were no statistical differences in changes of VNS, NDI, and effectiveness between these two groups. The proportion of patients with successful treatment is illustrated as 62.5% in US-guided group and 58% in FL-guided group at 12 months. There were no significant differences between the groups or during follow-up periods. Three cases of the intravascular injections were done in FL-guided group.ConclusionThe US-guided selective cervical nerve root blocks are facilitated by identifying critical vessels at unexpected locations relative to the foramen and to protect injury to such vessels, which is the leading cause of reported complications from FL-guided transforaminal blocks. On treatment effect, significant long-term improvements in functions and pain reliefs were observed in both groups after the intervention. However, significant differences were not observed between the groups. Therefore, the US-guided selective cervical nerve root block was shown to be as effective as the FL-guided transforaminal block in pain reliefs and functional improvements, in addition to the absence of radiation and protection vessel injury at real-time imaging.

Subdural spread of injected local anesthetic in a selective transforaminal cervical nerve root block: a case report

IntroductionAlthough uncommon, selective cervical nerve root blocks can have serious complications. The most serious complications that have been reported include cerebral infarction, spinal cord infarction, transient quadriplegia and death.Case presentationA 40-year-old Japanese woman with a history of severe right-sided cervical radicular pain was scheduled to undergo a right-sided C6 selective cervical nerve root block using a transforaminal approach under fluoroscopic guidance. An anterior oblique view of the C5-C6 intervertebral foramen was obtained, and a 23-gauge spinal needle, connected to the normal extension tube with a syringe filled with contrast medium, was introduced into the posterior-caudal aspect of the C5-C6 intervertebral foramen on the right side. In the anteroposterior view, the placement of the needle was considered satisfactory when it was placed no more medial than halfway across the width of the articular pillar. Although the spread of the contrast medium along the C6 nerve root was observed with right-sided C6 radiculography, the subdural flow of the contrast medium was not observed with real-time fluoroscopy. The extension tube used for the radiculography was removed from the spinal needle and a normal extension tube with a syringe filled with lidocaine connected in its place. We performed a negative aspiration test and then injected 1.5 mL of 1.0% lidocaine slowly around the C6 nerve root. Immediately after the injection of the local anesthetic, our patient developed acute flaccid paralysis, complained of breathing difficulties and became unresponsive; her respiratory pattern was uncoordinated. After 20 minutes, she regained consciousness and became alert, and her muscle strength in all four limbs returned to normal without any sensory deficits after receiving emergent cardiorespiratory support.ConclusionsWe believe that confirming maintenance of the appropriate needle position in the anteroposterior view by injecting local anesthetic is important for preventing central needle movement. Because the potential risk of serious complications cannot be completely eliminated during the use of any established selective cervical nerve root block procedure, preparation for an emergency airway, ventilation and cardiovascular support is indispensable in cases of high spinal cord anesthesia.

Horner Syndrome Following a Selective Cervical Nerve Root Block

A 31-year-old man with cervical degenerative disc disease was seen at an outside institution for a right selective nerve root block at C7. Following the procedure, he had right ptosis and miosis. Pharmacologic testing confirmed a right Horner syndrome. MRI and MRA showed no arterial dissection. This report documents the unusual occurrence of permanent Horner syndrome following a selective cervical nerve root block.

CT-Guided Cervical Selective Nerve Root Block with a Dorsal Approach

Cervical transforaminal blocks are frequently performed to treat cervical radicular pain. These blocks are performed mostly under fluoroscopy, but a CT-guided technique has also been described. The aim of this study was to review the results of CT-guided CSNRB by using a dorsal approach, to describe the contrast patterns achieved with this injection technique, and to estimate the degree of specificity and sensitivity. We used a CT-guided technique with a dorsal approach leading to a more extra-than transforaminal but a selective nerve root block as well. Of 53 blocks, we performed 38 for diagnostic and 15 for therapeutic indications. Pain relief was measured hourly on a VAS. The distribution of contrast and the angle of the trajectory of the injection needle were analyzed as well as the degree of pain relief. Contrast was found in the intraforaminal region in 8 (15%) blocks, extraforaminally in 40 (78%) blocks, and intraspinally in 3 (6%) blocks. The mean angle between the needle and the sagittal plane was 26.6° (range, from 1° to 50°). The mean distance between needle tip and nerve root was 4.43 mm (range, 0-20 mm). Twenty-six (68.4%) of the 38 diagnostic blocks led to a decrease in the pain rating of >50%. There were no complications or unintended side effects, apart from occasional local puncture pain. We conclude that CT-guided CSNRBs using a dorsal approach are feasible and that they are sensitive and specific.