Best Practices for Minimally Invasive Lumbar Spinal Stenosis Treatment 2.0 (MIST): Consensus Guidance from the American Society of Pain and Neuroscience (ASPN)

Introduction

Methods

Results

Discussion

Conclusion

The Neurostimulation Appropriateness Consensus Committee (NACC): Recommendations for Surgical Technique for Spinal Cord Stimulation

INTRODUCTION

The field of neurostimulation for the treatment of chronic pain is a rapidly developing area of medicine. Although neurostimulation therapies have advanced significantly as a result of technologic improvements, surgical planning, device placement, and postoperative care are of equal importance to optimize outcomes. This Neurostimulation Appropriateness Consensus Committee (NACC) project intends to provide evidence-based guidance for these often-overlooked areas of neurostimulation practice.

MATERIALS AND METHODS

Authors were chosen based on their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from the last NACC publication in 2017 to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on evidence strength and consensus when evidence was scant.

RESULTS

This NACC project provides guidance on preoperative assessment, intraoperative techniques, and postoperative management in the form of consensus points with supportive evidence. These results are based on grade of evidence, strength of consensus, and expert opinion.

CONCLUSIONS

The NACC has given guidance for a surgical plan that encompasses the patient journey from the planning stage through the surgical experience and postoperative care. The overall recommendations are designed to improve efficacy and the safety of patients undergoing these neuromodulation procedures and are intended to apply throughout the international community.

Characterization and virulence factors distribution of blaCTX-M and mcr-1carrying Escherichia coli isolates from bovine mastitis

AIM

To investigate the occurrence of ESBL and colistin-resistant E. coli and its genotypic characterization and identification of virulence determinants in cases of bovine mastitis in three provinces of China.

MATERIALS AND METHODS

Five hundred and thirty-five milk samples presenting mastitis symptoms were screened for the presence of ESBL, colistin-resistant and different virulence genes. Susceptibility testing was identified by the micro-dilution method. Escherichia coli isolates were used to detect ESBL genes (bla_CTX-M , bla_SHV and bla_TEM ) and colistin-resistant genes mcr-(1-9). Multiplex PCR approach was used for the detection of major bla_CTX-M groups, different phylogroups and virulence genes. The clonal relationship was then evaluated with MLST, MLSA and PFGE.

RESULTS

Multi-drug resistance (MDR) was found in more than 85% of ESBL and colistin-resistant E. coli isolates. Genotypic characterization showed a dominance of the bla_CTX-M-1 group, and the most prevalent alleles observed were bla_CTX-M-28 (38·37%), bla_CTX-M-14 (17·44%), bla_CTX-M-66 (13·95%) and bla_CTX-M-55 (10·46%). The targeted virulence genes were detected in 97·89% of isolates. Sequence types ST58 and ST410 were the most predominant (2/20 = 20%). The majority of the E. coli isolates carrying ESBL and mcr-1 were clonally unrelated.

CONCLUSION

High level of association was observed between ESBL-producing and COL-resistance in E. coli of bovine mastitis.

SIGNIFICANCE AND IMPACT OF THE STUDY

To the best of our knowledge, this is the first report which shows the genetic diversity of ESBL and mcr-1, and various virulent features of E. coli strains isolated from bovine clinical mastitis in three different provinces of China. The major carriers of the bla_CTX-M-1 and bla_CTX-M-9 were bla_CTX-M-28 and bla_CTX-M-14 alleles respectively. The association of ESBL-producing E. coli with mcr-1 is of particular concern.

A Systematic Literature Review of Peripheral Nerve Stimulation Therapies for the Treatment of Pain

Objective

To conduct a systematic literature review of peripheral nerve stimulation (PNS) for pain.

Design

Grade the evidence for PNS.

Methods

An international interdisciplinary work group conducted a literature search for PNS. Abstracts were reviewed to select studies for grading. Inclusion/exclusion criteria included prospective randomized controlled trials (RCTs) with meaningful clinical outcomes that were not part of a larger or previously reported group. Excluded studies were retrospective, had less than two months of follow-up, or existed only as abstracts. Full studies were graded by two independent reviewers using the modified Interventional Pain Management Techniques–Quality Appraisal of Reliability and Risk of Bias Assessment, the Cochrane Collaborations Risk of Bias assessment, and the US Preventative Services Task Force level-of-evidence criteria.

Results

Peripheral nerve stimulation was studied in 14 RCTs for a variety of painful conditions (headache, shoulder, pelvic, back, extremity, and trunk pain). Moderate to strong evidence supported the use of PNS to treat pain.

Conclusion

Peripheral nerve stimulation has moderate/strong evidence. Additional prospective trials could further refine appropriate populations and pain diagnoses.

A Systematic Literature Review of Spine Neurostimulation Therapies for the Treatment of Pain

Objective

To conduct a systematic literature review of spinal cord stimulation (SCS) for pain.

Design

Grade the evidence for SCS.

Methods

An international, interdisciplinary work group conducted literature searches, reviewed abstracts, and selected studies for grading. Inclusion/exclusion criteria included randomized controlled trials (RCTs) of patients with intractable pain of greater than one year’s duration. Full studies were graded by two independent reviewers. Excluded studies were retrospective, had small numbers of subjects, or existed only as abstracts. Studies were graded using the modified Interventional Pain Management Techniques–Quality Appraisal of Reliability and Risk of Bias Assessment, the Cochrane Collaborations Risk of Bias assessment, and the US Preventative Services Task Force level-of-evidence criteria.

Results

SCS has Level 1 evidence (strong) for axial back/lumbar radiculopathy or neuralgia (five high-quality RCTs) and complex regional pain syndrome (one high-quality RCT).

Conclusions

High-level evidence supports SCS for treating chronic pain and complex regional pain syndrome. For patients with failed back surgery syndrome, SCS was more effective than reoperation or medical management. New stimulation waveforms and frequencies may provide a greater likelihood of pain relief compared with conventional SCS for patients with axial back pain, with or without radicular pain.

Localized Corticosteroid Injections for Malignant Joint Pain in the Oncologic Population: A Case Series

Pain is a common issue that is present in cancer survivors as well as those with active malignant processes. Despite opioid analgesics and adjuvant therapies such as systemic corticosteroids, many patients have persistent localized pain. We describe a case series of 3 cancer patients who have concurrent hip- and greater trochanteric-related pain. We performed a single-insertion-site, ultrasound-guided injection to target both the intra-articular hip and greater trochanteric bursa for each patient. All patients reported an improvement in pain symptoms and function with no major complications. Targeted corticosteroid injections provide a potential for relief of malignant joint pain.

Cervical Medial Branch Block Volume Dependent Dispersion Patterns as a Predictor for Ablation Success: A Cadaveric Study

BACKGROUND

Neck pain is one of the most common causes of chronic pain and the fourth leading cause of disability worldwide; it is estimated that between 36% and 67% of this pain is due to facet arthropathy. For patients who have pain refractory to conservative treatments literature supports management with diagnostic cervical medial branch blocks (MBBs) to identify the associated facet innervation as the source of pain followed by therapeutic radiofrequency ablation (RFA) of the identified nerves. Cervical RFA has good published outcomes; however, the procedure is dependent upon the specificity of the diagnostic block to achieve maximal success. Currently, this prerequisite test has false positive rates between 27% and 63% and recent studies have shown that this may, in part, be a consequence of currently accepted injection volumes of 0.50 mL or more, which may decrease the sensitivity of MBBs.

OBJECTIVE

To evaluate the possible differences in volume dispersion between 0.25 and 0.50 mL of injectate during cervical MBBs.

STUDY DESIGN

Cadaveric study.

SETTING

An academic medical center in the United States.

PATIENTS

Not applicable.

METHODS

This was a cadaveric study in which six subjects were chosen with intact cervical spines. Cervical MBB were performed bilaterally at the midcervical spine, using a posterior approach under fluoroscopic guidance. 0.25 or 0.50 mL of a 9:1 solution of Omnipaque 180 mg iodine/mL and 1% medical grade methylene blue were administered on the left and right sides, respectively. Postinjection computed tomography (CT) imaging and gross dissection were performed to assess injectate spread.

MAIN OUTCOME MEASURES

Outcome measures after using commonly injected volumes for cervical MBB, included visualized and measured spread (by CT and gross dissection) of cervical medial branch blocks, coating adjacent structures not targeted by RFA.

RESULTS

Postinjection CT imaging and cadaveric dissection demonstrated that, although both volumes adequately coated the medial branches, the 0.50 mL cohort reliably spread dorsally to superficial muscles (splenius) and nerves distant from the targeted nerves (dorsal motor branches to splenius), whereas the 0.25 mL injectate cohort was contained in the deep and intermediate muscular cervical layers directly juxtaposed to the targeted cMBBs.

CONCLUSION

Results suggest that 0.50 mL injections of local anesthetic during cervical MBBs contacts many nonintended targets, thus decreasing the specificity of a targeted diagnostic cervical MBB. Furthermore, we demonstrated that 0.25 mL of injectate reliably bathed the cervical medial branches without extensive extravasation. This indicates that there would potentially be fewer local anesthetic effects on distant tissues, increasing the specificity of cervical MBBs and likely improving RFA planning.

Lumbar Medial Branch Block Volume-Dependent Dispersion Patterns as a Predictor for Ablation Success: A Cadaveric Study

BACKGROUND

Lumbar facet arthropathy is a common cause of low back pain. Literature supports treatment with radiofrequency ablation (RFA) of associated nerves that innervate lumbar facets when alternative conservative therapies have failed. Diagnostic local anesthetic blocks precede therapeutic ablation, but have a false-positive rate of 27%-63%, and some authors have questioned their utility in predicting therapeutic response to RFA. The authors of the current study believe that injectate volume may be a contributing factor to false positivity.

OBJECTIVE

To evaluate the difference in volume dispersion between 0.25 mL and 0.5 mL of injectate when performing lumbar medial branch blocks. We hypothesized that injection volumes greater than 0.25 mL during lumbar medial branch blocks would affect the distal branches of the adjacent medial branches, thus decreasing the specificity of the procedure. Thus, we attempted to demonstrate that injection volumes greater than 0.25 mL during lumbar medial branch blocks would affect the distal branches of the adjacent medial branches, which might increase false positivity of the blocks.

STUDY DESIGN

Cadaveric investigation.

SETTING

Tertiary care center.

PARTICIPANTS

Not applicable.

OUTCOME MEASUREMENTS

To demonstrate that the spread of lumbar medial branch blocks using commonly injected volume coats adjacent structures that are not affected by radiofrequency ablation.

METHODS

Six cadavers were chosen with nondissected lumbar spines. Fluoroscopically guided medial branch injections were performed bilaterally using the posterior oblique approach. A volume of 0.25 mL or 0.50 mL of a 9:1 solution of Omnipaque 240 and 1% medical grade methylene blue were delivered to the left and right sides, respectively. Postinjection computed tomographic imaging was performed, followed by dissection.

RESULTS

Both volumes adequately coated the medial branches, but in the 0.5-mL injectate cohort there was consistent spread dorsally to the superficial muscles and distal segments of the dorsal branches distant to the target nerves, whereas in the 0.25-mL injectate cohort the spread was contained in the deep and intermediate muscular lumbar layers, close to the intended target.

CONCLUSION

We suggest that a 0.5-mL injectate volume in clinical practice may produce an adjacent-level nerve block in addition to the intended injection level, thus decreasing the specificity of a targeted lumbar medial branch block. A 0.25-mL quantity of injectate reliably contacted the lumbar medial branches without extensive extravasation. Presumably, this means that 0.25 mL total volume for a lumbar medial branch block may provide greater specificity for RFA planning.

LEVEL OF EVIDENCE

NA.

Hypodermis Tension Loop: A New Preventative Measure for Lead Migration in the Morbidly Obese

Electrode migration/displacement is reported to be the most common complication of spinal cord stimulator (SCS) implantation, with the literature reporting incidences from 13.2% to 22.6%. There have been numerous publications describing techniques preventing lead migration, with most involving tying leads to skin and fascia for trial and permanent leads, respectively. However, few have addressed how to prevent migration in the case of hypermobile tissue seen in the morbidly obese. We describe the creation of subcutaneous tension loops to prevent lead migration.

Hyperhomocysteinemia masquerading as pulmonary embolism

We describe a 30-year-old male who presented with acute onset of breathlessness, tachycardia, and palpitations associated with distension of jugular vein and clear lungs on physical examination. The chest X-ray was normal and ECG was showing S1Q3T3 and right ventricular strain pattern. His 2-D echocardiography was showing dilated right atrium, right ventricular dilatation and moderate pulmonary arterial hypertension. He was found to have thrombosis involving left side of deep venous system with normal superficial venous system (Doppler proved). All routine blood investigations for etiology of recurrent DVT were normal except serum homocyteine level, which was significantly raised. Megaloblastic anemia on peripheral smear and hyperhomocysteinemia prompted us to search for its cause, which was subsequently found to be vitamin B12 deficiency. Such an association of megaloblastic anemia due to vitamin B12 deficiency leading to hyperhomocysteinemia and subsequent thrombosis in left venous system presenting as acute pulmonary embolism has not been described earlier in the medical literature.

Squamous cell carcinoma of the splenic flexure of the colon

A partially obstructing lesion of the splenic flexure was discovered during a barium enema examination, and subsequent colonoscopy and biopsy demonstrated a squamous cell carcinoma. This is the first reported instance of squamous cell carcinoma of the colon in which the splenic flexure has been involved. The case is discussed, and the recent literature on this entity is reviewed.