Faculty Bibliography

Lumbar fusion is an accepted and effective technique for the treatment of lumbar degenerative disease. The practice has evolved continually since Albee and Hibbs independently reported the first cases in 1913, and advancements in both technique and patient selection continue through the present day. Clinical and radiological indications for surgery have been tested in trials, and other diagnostic modalities have developed and been studied. Fusion practices have also advanced; instrumentation, surgical approaches, biologics, and more recently, operative planning, have undergone stark changes at a seemingly increasing pace over the last decade. As the general population ages, treatment of degenerative lumbar disease will become a more prevalent-and costlier-issue for surgeons as well as the healthcare system overall. This review will cover the evolution of indications and techniques for fusion in degenerative lumbar disease, with emphasis on the evidence for current practices.

BACKGROUND:Radiological evaluation of traumatic thoracolumbar fractures is used to classify the injury and determine the optimal treatment plan. Currently, there remains a lack of consensus regarding appropriate radiological protocol. Most clinicians use a combination of plain radiographs, 3-dimensional computed tomography with reconstructions, and magnetic resonance imaging (MRI). OBJECTIVE:To determine, through evidence-based guidelines review: (1) whether the use of MRI to identify ligamentous integrity predicted the need for surgical intervention; and (2) if there are any radiological findings that can assist in predicting clinical outcomes. METHODS:A systematic review of the literature was performed using the National Library of Medicine/PubMed database and the Cochrane Library for studies relevant to thoracolumbar trauma. Clinical studies specifically addressing the radiological evaluation of thoracolumbar spine trauma were selected for review. RESULTS:Two of 2278 studies met inclusion criteria for review. One retrospective review (Level III) and 1 prospective cohort (Level III) provided evidence that the addition of an MRI scan in acute thoracic and thoracolumbar trauma can predict the need for surgical intervention. There was insufficient evidence that MRI can help predict clinical outcomes in patients with acute traumatic thoracic and thoracolumbar spine injuries. CONCLUSION:This evidence-based guideline provides a Grade B recommendation that radiological findings in patients with acute thoracic or thoracolumbar spine trauma can predict the need for surgical intervention. This evidence-based guideline provides a grade insufficient recommendation that there is insufficient evidence to determine if radiographic findings can assist in predicting clinical outcomes in patients with acute thoracic and thoracolumbar spine injuries. QUESTION 1:Are there radiographic findings in patients with traumatic thoracolumbar fractures that can predict the need for surgical intervention? RECOMMENDATION 1:Because MRI has been shown to influence the management of up to 25% of patients with thoracolumbar fractures, providers may use MRI to assess posterior ligamentous complex integrity, when determining the need for surgery. Strength of Recommendation: Grade B. QUESTION 2:Are there radiographic findings in patients with traumatic thoracolumbar fractures that can assist in predicting clinical outcomes? RECOMMENDATION 2:Due to a paucity of published studies, there is insufficient evidence that radiographic findings can be used as predictors of clinical outcomes in thoracolumbar fractures. Strength of Recommendation: Grade Insufficient The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_3.

QUESTION 1:Are there classification systems for fractures of the thoracolumbar spine that have been shown to be internally valid and reliable (ie, do these instruments provide consistent information between different care providers)? RECOMMENDATION 1:A classification scheme that uses readily available clinical data (eg, computed tomography scans with or without magnetic resonance imaging) to convey injury morphology, such as Thoracolumbar Injury Classification and Severity Scale or the AO Spine Thoracolumbar Spine Injury Classification System, should be used to improve characterization of traumatic thoracolumbar injuries and communication among treating physicians. Strength of Recommendation: Grade B. QUESTION 2:In treating patients with thoracolumbar fractures, does employing a formally tested classification system for treatment decision-making affect clinical outcomes? RECOMMENDATION 2:There is insufficient evidence to recommend a universal classification system or severity score that will readily guide treatment of all injury types and thereby affect outcomes. Strength of Recommendation: Grade Insufficient The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_2.

BACKGROUND:The thoracic and lumbar ("thoracolumbar") spine are the most commonly injured region of the spine in blunt trauma. Trauma of the thoracolumbar spine is frequently associated with spinal cord injury and other visceral and bony injuries. Prolonged pain and disability after thoracolumbar trauma present a significant burden on patients and society. OBJECTIVE:To formulate evidence-based clinical practice recommendations for the care of patients with injuries to the thoracolumbar spine. METHODS:A systematic review of the literature was performed using the National Library of Medicine PubMed database and the Cochrane Library for studies relevant to thoracolumbar spinal injuries based on specific clinically oriented questions. Relevant publications were selected for review. RESULTS:For all of the questions posed, the literature search yielded a total of 6561 abstracts. The task force selected 804 articles for full text review, and 78 were selected for inclusion in this overall systematic review. CONCLUSION:The available evidence for the evaluation and treatment of patients with thoracolumbar spine injuries demonstrates considerable heterogeneity and highly variable degrees of quality. However, the workgroup was able to formulate a number of key recommendations to guide clinical practice. Further research is needed to counter the relative paucity of evidence that specifically pertains to patients with only thoracolumbar spine injuries. The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_1.

QUESTION 1:Which neurological assessment tools have demonstrated internal reliability and validity in the management of patients with thoracic and lumbar fractures (ie, do these instruments provide consistent information between different care providers)? RECOMMENDATION 1:Numerous neurologic assessment scales (Functional Independence Measure, Sunnybrook Cord Injury Scale and Frankel Scale for Spinal Cord Injury) have demonstrated internal reliability and validity in the management of patients with thoracic and lumbar fractures. Unfortunately, other contemporaneous measurement scales (ie, American Spinal Cord Injury Association Impairment Scale) have not been specifically studied in patients with thoracic and lumbar fractures. Strength of Recommendation: Grade C. QUESTION 2:Are there any clinical findings (eg, presenting neurological grade/function) in patients with thoracic and lumbar fractures that can assist in predicting clinical outcomes? RECOMMENDATION 2:Entry American Spinal Injury Association Impairment Scale grade, sacral sensation, ankle spasticity, urethral and rectal sphincter function, and AbH motor function can be used to predict neurological function and outcome in patients with thoracic and lumbar fractures (Table I https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_4_table1). Strength of Recommendation: Grade B The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_4.

QUESTION:Does the choice of surgical approach (anterior, posterior, or combined anterior-posterior) improve clinical outcomes in patients with thoracic and lumbar fractures? RECOMMENDATIONS:In the surgical treatment of patients with thoracolumbar burst fractures, physicians may use an anterior, posterior, or a combined approach as the selection of approach does not appear to impact clinical or neurological outcomes. Strength of Recommendation: Grade B With regard to radiologic outcomes in the surgical treatment of patients with thoracolumbar fractures, physicians may utilize an anterior, posterior, or combined approach because there is conflicting evidence in the comparison among approaches. Strength of Recommendation: Grade Insufficient With regard to complications in the surgical treatment of patients with thoracolumbar fractures, physicians may use an anterior, posterior, or combined approach because there is conflicting evidence in the comparison among approaches. Strength of Recommendation: Grade Insufficient The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_11.

Enhancing genetic resistance of chickens to Newcastle Disease Virus (NDV) provides a promising way to improve poultry health, and to alleviate poverty and food insecurity in developing countries. In this study, two inbred chicken lines with different responses to NDV, Fayoumi and Leghorn, were challenged with LaSota NDV strain at 21 days of age. Through transcriptome analysis, gene expression in spleen at 2 and 6 days post-inoculation was compared between NDV-infected and control groups, as well as between chicken lines. At a false discovery rate <0.05, Fayoumi chickens, which are relatively more resistant to NDV, showed fewer differentially expressed genes (DEGs) than Leghorn chickens. Several interferon-stimulated genes were identified as important DEGs regulating immune response to NDV in chicken. Pathways predicted by IPA analysis, such as "EIF-signaling", "actin cytoskeleton organization nitric oxide production" and "coagulation system" may contribute to resistance to NDV in Fayoumi chickens. The identified DEGs and predicted pathways may contribute to differential responses to NDV between the two chicken lines and provide potential targets for breeding chickens that are more resistant to NDV.

OBJECT/OBJECTIVE:The authors have established a multicenter registry to assess the efficacy and costs of common lumbar spinal procedures using prospectively collected outcomes. Collection of these data requires an extensive commitment of resources from each site. The aim of this study was to determine whether outcomes data from shorter-interval follow-up could be used to accurately estimate long-term outcome following lumbar discectomy. METHODS:An observational prospective cohort study was completed at 13 academic and community sites. Patients undergoing single-level lumbar discectomy for treatment of disc herniation were included. SF-36 and Oswestry Disability Index (ODI) data were obtained preoperatively and at 1, 3, 6, and 12 months postoperatively. Quality-adjusted life year (QALY) data were calculated using SF-6D utility scores. Correlations among outcomes at each follow-up time point were tested using the Spearman rank correlation test. RESULTS:One hundred forty-eight patients were enrolled over 1 year. Their mean age was 46 years (49% female). Eleven patients (7.4%) required a reoperation by 1 year postoperatively. The overall 1-year follow-up rate was 80.4%. Lumbar discectomy was associated with significant improvements in ODI and SF-36 scores (p < 0.0001) and with a gain of 0.246 QALYs over the 1-year study period. The greatest gain occurred between baseline and 3-month follow-up and was significantly greater than improvements obtained between 3 and 6 months or 6 months and 1 year(p < 0.001). Correlations between 3-month, 6-month, and 1-year outcomes were similar, suggesting that 3-month data may be used to accurately estimate 1-year outcomes for patients who do not require a reoperation. Patients who underwent reoperation had worse outcomes scores and nonsignificant correlations at all time points. CONCLUSIONS:This national spine registry demonstrated successful collection of high-quality outcomes data for spinal procedures in actual practice. Three-month outcome data may be used to accurately estimate outcome at future time points and may lower costs associated with registry data collection. This registry effort provides a practical foundation for the acquisition of outcome data following lumbar discectomy.