Factor analysis of the North American Spine Society outcome assessment instrument: a study based on a spine registry of patients treated with lumbar and cervical disc arthroplasty

Background contextStudies involving factor analysis (FA) of the items in the North American Spine Society (NASS) outcome assessment instrument have revealed inconsistent factor structures for the individual items.PurposeThis study examined whether the factor structure of the NASS varied in relation to the severity of the back/neck problem and differed from that originally recommended by the developers of the questionnaire, by analyzing data before and after surgery in a large series of patients undergoing lumbar or cervical disc arthroplasty.Study design/settingProspective multicenter observational case series.Patient sampleThree hundred ninety-one patients with low back pain and 553 patients with neck pain completed questionnaires preoperatively and again at 3 to 6 and 12 months follow-ups (FUs), in connection with the SWISSspine disc arthroplasty registry.Outcome measuresNorth American Spine Society outcome assessment instrument.MethodsFirst, an exploratory FA without a priori assumptions and subsequently a confirmatory FA were performed on the 17 items of the NASS-lumbar and 19 items of the NASS-cervical collected at each assessment time point. The item-loading invariance was tested in the German version of the questionnaire for baseline and FU.ResultsBoth NASS-lumbar and NASS-cervical factor structures differed between baseline and postoperative data sets. The confirmatory analysis and item-loading invariance showed better fit for a three-factor (3F) structure for NASS-lumbar, containing items on “disability,” “back pain,” and “radiating pain, numbness, and weakness (leg/foot)” and for a 5F structure for NASS-cervical including disability, “neck pain,” “radiating pain and numbness (arm/hand),” “weakness (arm/hand),” and “motor deficit (legs).”ConclusionsThe best-fitting factor structure at both baseline and FU was selected for both the lumbar- and cervical-NASS questionnaires. It differed from that proposed by the originators of the NASS instruments. Although the NASS questionnaire represents a valid outcome measure for degenerative spine diseases, it is able to distinguish among all major symptom domains (factors) in patients undergoing lumbar and cervical disc arthroplasty; overall, the item structure could be improved. Any potential revision of the NASS should consider its factorial structure; factorial invariance over time should be aimed for, to allow for more precise interpretations of treatment success.     

An evidence-based clinical guideline for the diagnosis and treatment of lumbar disc herniation with radiculopathy

Background contextThe objective of the North American Spine Society's (NASS) Evidence-Based Clinical Guideline for the Diagnosis and Treatment of Lumbar Disc Herniation with Radiculopathy is to provide evidence-based recommendations to address key clinical questions surrounding the diagnosis and treatment of lumbar disc herniation with radiculopathy. The guideline is intended to reflect contemporary treatment concepts for symptomatic lumbar disc herniation with radiculopathy as reflected in the highest quality clinical literature available on this subject as of July 2011. The goals of the guideline recommendations are to assist in delivering optimum efficacious treatment and functional recovery from this spinal disorder.PurposeTo provide an evidence-based educational tool to assist spine specialists in the diagnosis and treatment of lumbar disc herniation with radiculopathy.Study designSystematic review and evidence-based clinical guideline.MethodsThis guideline is a product of the Lumbar Disc Herniation with Radiculopathy Work Group of NASS' Evidence-Based Guideline Development Committee. The work group consisted of multidisciplinary spine care specialists trained in the principles of evidence-based analysis. A literature search addressing each question and using a specific search protocol was performed on English-language references found in Medline, Embase (Drugs and Pharmacology), and four additional evidence-based databases to identify articles. The relevant literature was then independently rated using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final recommendations to answer each clinical question were developed via work group discussion, and grades were assigned to the recommendations using standardized grades of recommendation. In the absence of Level I to IV evidence, work group consensus statements have been developed using a modified nominal group technique, and these statements are clearly identified as such in the guideline.ResultsTwenty-nine clinical questions were formulated and addressed, and the answers are summarized in this article. The respective recommendations were graded by strength of the supporting literature, which was stratified by levels of evidence.ConclusionsThe clinical guideline has been created using the techniques of evidence-based medicine and best available evidence to aid practitioners in the care of patients with symptomatic lumbar disc herniation with radiculopathy. The entire guideline document, including the evidentiary tables, suggestions for future research, and all the references, is available electronically on the NASS Web site at http://www.spine.org/Pages/PracticePolicy/ClinicalCare/ClinicalGuidlines/Default.aspx and will remain updated on a timely schedule.     

Conflict of interest and professional medical associations: the North American Spine Society experience

Background contextRecently the financial relationships between industry and professional medical associations have come under increased scrutiny because of the concern that industry ties may create real or perceived conflicts of interest. Professional medical associations pursue public advocacy as well as promote medical education, develop clinical practice guidelines, fund research, and regulate professional conduct. Therefore, the conflicts of interest of a professional medical association and its leadership can have more far-reaching effects on patient care than those of an individual physician.PurposeFew if any professional medical associations have reported their experience with implementing strict divestment and disclosure policies, and among the policies that have been issued, there is little uniformity. We describe the experience of the North American Spine Society (NASS) in implementing comprehensive conflicts of interest policies.Study designA special feature article.MethodsWe discuss financial conflicts of interest as they apply to professional medical associations rather than to individual physicians. We describe the current policies of disclosure and divestment adopted by the NASS and how these policies have evolved, been refined, and have had no detrimental impact on membership, attendance at annual meetings, finances, or leadership recruitment. No funding was received for this work. The authors report no potential conflict-of-interest-associated biases in the text.ResultsThe NASS has shown that a professional medical association can manage its financial relationships with industry in a manner that minimizes influence and bias.ConclusionsThe NASS experience can provide a template for other professional medical associations to help manage their own possible conflicts of interest issues.     

Evaluation of the North American Spine Society Instrument for assessment of health status in patients with chronic backache

PURPOSE OF THE STUDY: The translation/back and translation and validation of the North American Spine Society (NASS) Instrument in German was published recently. This contribution aims at describing the scoring of this questionnaire. METHOD: The scoring is oriented on the recommendations of the developing scientists of the US-American original, with whom we cooperated during the German validation. RESULTS: The scoring algorithm is described, a program for computerized scoring in SPSS was written. Program syntax and the questionnaire are reproduced. CONCLUSION: The contribution enables interested researchers to apply and score the NASS questionnaire in German-speaking countries.     

Validation of the North American Spine Society Instrument for assessment of health status in patients with chronic backache]

BACKGROUND: Pain and functional limitations are the chief symptoms in patients with back pain. However, standardized assessment of these domains are still not commonplace in clinical practice. The objective of this study was the cultural adaptation and validation of the North American Spine Society (NASS) Lumbar Spine Outcome Assessment Instrument for German speaking patients with back pain. METHODS: Translation and backtranslation of the NASS instrument was performed according to international recommendations. 56 consecutive inpatients with a confirmed diagnosis of dorsopathia completed a German version of the NASS instrument, the SF-36 and an established German instrument for back patients (FFbH-R). All patients completed the questionnaires 48 hours apart to assess test-retest reliability. Validity was assessed through correlation with corresponding subscales of the SF-36, the FFbH-R and a 0-10 pain numeric rating scale. Internal consistency and item-to-scale correlation served as statistics of reliability. RESULTS: The two subscales of the NASS Instrument for cervical and lumbar problems correlate significantly with the corresponding subscales of the FFbH-R and the SF-36 (r = 0.28-0.83, p < 0.05) and 0.39-0.68 (p < 0.05) with a pain numeric rating scale. Test-retest reliability demonstrated intraclass correlation coefficients between 0.82 to 0.89. CONCLUSION: The German version of the NASS Cervical and Lumbar Spine Outcome Assessment Instrument allows the standardized assessment of pain, functional limitations and neurogenic symptoms in patients with back pain and the international comparison of health states and therapeutic outcomes.     

A computer touch-screen version of the North American Spine Society outcome assessment instrument for the lumbar spine

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients' acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients' preferences and minimising administrative work.     

Artificial intervertebral discs and beyond: a North American Spine Society Annual Meeting symposium.

BACKGROUND CONTENT: This is a synopsis of a symposium presented to the North American Spine Society Annual Meeting in Seattle, WA, 2001. PURPOSE: To bring to the reader who may not have attended the symposium a distillation of the material presented on this frontier of spinal surgery. METHODS: Panel presentation. RESULTS: The proposed indication for artificial disc replacement is a degenerated but contained disc, painful to the point of major life-style interruption, refractory to at least 1 year of nonoperative treatment, preferably at a single lumbar level and without infection, listhesis or major facet joint disease or spinal stenosis. Total disc replacements have been developed and used mostly in Europe. Disc nucleus replacements have also been developed. No disc replacement has been approved for general use in North America as yet. The US Food and Drug Administration is conducting investigational device exemption studies at this time. CONCLUSIONS: Artificial disc replacement is not a new concept, the first attempts having been done in the early 1950s. During the past 15 years, considerable advance has been made with large numbers of patients, mostly in Europe, having surgery with either total disc prostheses or disc nucleus replacements. Only with truly scientific studies using patient randomization, pre- and postsurgery outcome analyses by unbiased independent observers and statistical analysis by independent experts will the real value of these devices be realized.     

An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spondylolisthesis

Background ContextThe objective of the North American Spine Society (NASS) evidence-based clinical guideline on the diagnosis and treatment of degenerative lumbar spondylolisthesis is to provide evidence-based recommendations on key clinical questions concerning the diagnosis and treatment of degenerative lumbar spondylolisthesis. The guideline is intended to address these questions based on the highest quality clinical literature available on this subject as of January 2007. The goal of the guideline recommendations is to assist the practitioner in delivering optimum, efficacious treatment of and functional recovery from this common disorder.PurposeTo provide an evidence-based, educational tool to assist spine care providers in improving the quality and efficiency of care delivered to patients with degenerative lumbar spondylolisthesis.Study DesignSystematic review and evidence-based clinical guideline.MethodsThis report is from the Degenerative Lumbar Spondylolisthesis Work Group of the NASS Evidence-Based Clinical Guideline Development Committee. The work group was comprised of multidisciplinary spine care specialists, all of whom were trained in the principles of evidence-based analysis. Each member participated in the development of a series of clinical questions to be addressed by the group. The final questions agreed on by the group are the subject of this report. A literature search addressing each question and using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology) and four additional, evidence-based, databases. The relevant literature was then independently rated by at least three reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final grades of recommendation for the answer to each clinical question were arrived at via face-to-face meetings among members of the work group using standardized grades of recommendation. When Level I–IV evidence was insufficient to support a recommendation to answer a specific clinical question, expert consensus was arrived at by the work group through the modified nominal group technique and is clearly identified as such in the guideline.ResultsNineteen clinical questions were formulated, addressing issues of prognosis, diagnosis, and treatment of degenerative lumbar spondylolisthesis. The answers to these 19 clinical questions are summarized in this document. The respective recommendations were graded by the strength of the supporting literature that was stratified by levels of evidence.ConclusionsA clinical guideline for degenerative lumbar spondylolisthesis has been created using the techniques of evidence-based medicine and using the best available evidence as a tool to aid practitioners involved with the care of this condition. The entire guideline document, including the evidentiary tables, suggestions for future research, and all references, is available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.     

An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spinal stenosis (update)

Background contextThe evidence-based clinical guideline on the diagnosis and treatment of degenerative lumbar spinal stenosis by the North American Spine Society (NASS) provides evidence-based recommendations to address key clinical questions surrounding the diagnosis and treatment of degenerative lumbar spinal stenosis. The guideline is intended to reflect contemporary treatment concepts for symptomatic degenerative lumbar spinal stenosis as reflected in the highest quality clinical literature available on this subject as of July 2010. The goals of the guideline recommendations are to assist in delivering optimum efficacious treatment and functional recovery from this spinal disorder.PurposeProvide an evidence-based educational tool to assist spine care providers in improving quality and efficiency of care delivered to patients with degenerative lumbar spinal stenosis.Study designSystematic review and evidence-based clinical guideline.MethodsThis report is from the Degenerative Lumbar Spinal Stenosis Work Group of the NASS's Evidence-Based Clinical Guideline Development Committee. The work group consisted of multidisciplinary spine care specialists trained in the principles of evidence-based analysis. The original guideline, published in 2006, was carefully reviewed. A literature search addressing each question and using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology), and four additional, evidence-based, databases to identify articles published since the search performed for the original guideline. The relevant literature was then independently rated by a minimum of three physician reviewers using the NASS-adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final recommendations to answer each clinical question were arrived at via work group discussion, and grades were assigned to the recommendations using standardized grades of recommendation. In the absence of Levels I to IV evidence, work group consensus statements have been developed using a modified nominal group technique, and these statements are clearly identified as such in the guideline.ResultsSixteen key clinical questions were assessed, addressing issues of natural history, diagnosis, and treatment of degenerative lumbar spinal stenosis. The answers are summarized in this document. The respective recommendations were graded by the strength of the supporting literature that was stratified by levels of evidence.ConclusionsA clinical guideline for degenerative lumbar spinal stenosis has been updated using the techniques of evidence-based medicine and using the best available clinical evidence to aid both practitioners and patients involved with the care of this condition. The entire guideline document, including the evidentiary tables, suggestions for future research, and all references, will be available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.     

Guideline summary review: an evidence-based clinical guideline for the diagnosis and treatment of low back pain

Background contextThe North American Spine Society's (NASS) Evidence Based Clinical Guideline for the Diagnosis and Treatment of Low Back Pain features evidence-based recommendations for diagnosing and treating adult patients with nonspecific low back pain. The guideline is intended to reflect contemporary treatment concepts for nonspecific low back pain as reflected in the highest quality clinical literature available on this subject as of February 2016.PURPOSEThe purpose of the guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for adult patients with nonspecific low back pain. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition.Study designThis is a guideline summary review.MethodsThis guideline is the product of the Low Back Pain Work Group of NASS’ Evidence-Based Clinical Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questions to address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members utilized NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guideline was submitted to an internal and external peer review process and ultimately approved by the NASS Board of Directors.ResultsEighty-two clinical questions were addressed, and the answers are summarized in this article. The respective recommendations were graded according to the levels of evidence of the supporting literature.ConclusionsThe evidence-based clinical guideline has been created using techniques of evidence-based medicine and best available evidence to aid practitioners in the diagnosis and treatment of adult patients with nonspecific low back pain. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flowchart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx     

Spine Explorer: a deep learning based fully automated program for efficient and reliable quantifications of the vertebrae and discs on sagittal lumbar spine MR images

BACKGROUND CONTEXTAlthough quantitative measurements improve the assessment of disc degeneration, acquirement of quantitative measurements relies on manual segmentation on lumbar magnetic resonance images (MRIs), which may introduce subjective bias. To date, only a few semiautomatic systems have been developed to quantify important components on MRIs.PURPOSETo develop a deep learning based program (Spine Explorer) for automated segmentation and quantification of the vertebrae and intervertebral discs on lumbar spine MRIs.STUDY DESIGNCross-sectional study.PATIENT SAMPLEThe study was extended on the Hangzhou Lumbar Spine Study, a population-based study of mainland Chinese with focuses on lumbar degenerative changes. From this population-based database, 50 sets lumbar MRIs were randomly selected as training dataset, and another 50 as test dataset.OUTCOME MEASURESRegions of vertebrae and discs were manually segmented on T2W sagittal MRIs to train a convolutional neural network for automated segmentation. Intersection-over-union was calculated to evaluate segmentation performance. Computational definitions were proposed to acquire quantitative morphometric and signal measurements for lumbar vertebrae and discs. MRIs in the test dataset were automatically measured with Spine Explorer and manually with ImageJ.METHODSIntraclass correlation coefficient (ICC) were calculated to examine inter-software agreements. Correlations between disc measurements and Pfirrmann score as well as age were examined to assess measurement validity.RESULTSThe trained Spine Explorer automatically segments and measures a lumbar MRI in half a second, with mean Intersection-over-union of 94.7% and 92.6% for the vertebra and disc, respectively. For both vertebra and disc measurements acquired with Spine Explorer and ImageJ, the agreements were excellent (ICC=0.81~1.00). Disc measurements significantly correlated to Pfirrmann score, and greater age was associated with greater anterior disc bulging area (r=0.35~0.44) and fewer signal measurements (r=−0.62~−0.77) as automatically acquired with Spine Explorer.CONCLUSIONSSpine Explorer is an efficient, accurate, and reliable tool to acquire comprehensive quantitative measurements for lumbar vertebra and disc. Implication of such deep learning based program can facilitate clinical studies of the lumbar spine.     

Dynesys系统治疗腰椎疾病的长期临床疗效观察

目的评估Dynesys系统治疗腰椎退变性疾病的长期临床安全性和有效性。方法回顾自2006年1月至2010年6月于本院实施Dynesys系统植入术患者共43例,男18例,女25例,年龄35～70岁,平均52．2岁,其中单纯退行性腰椎管狭窄者21例,腰椎管狭窄并椎间盘突出者15例,腰椎管狭窄伴退行性腰椎滑脱（I度滑脱）者5例,复发性腰椎间盘突出者2例,均经非手术治疗无效,于我院植入Dynesys系统。以疼痛视觉模拟评分（visual analoguescale,VAS）、Oswestry功能障碍指数评分（oswestry disability index,ODI）、椎间隙高度、椎间活动度（rangeofmotion,ROM）进行疗效评估;采用NASS指数评估患者满意度;观察患者行走距离、术后固定及邻近节段退变、并发症发生情况等。结果本组病例全部获得随访,时间27～54个月,平均39．5个月。术后3个月患者的腰痛VAS评分、腿痛VAS评分、ODI评分分别由术前的7．67分、6．77分、60．58分下降到2．93分、2．32分、26．02分（P〈0．01）;椎间隙高度由术前的9．73mm升高到12．50mm（P〈0．01）;步行距离由术前的10～1000m升高到均大于1000m;ROM值由术前的7．80。下降到5．26。（P〈0．01）。术后随访期间各时间点之间腰痛VAS评分、腿痛VAS评分、ODI评分、椎间隙高度、ROM值均无显著性差异（P〉0．05）,而与术前相比差异均有统计学意义（P〈0．01）。UCLA系统评价显示术后及随访期间固定节段及相邻节段未出现进一步退变。术中、术后及随访期间均未出现严重并发症。结论Dynesys系统对腰椎退变性患者具有良好的长期临床疗效,安全性高,值得进一步推广。     

Cross-cultural adaptation of the lumbar North American Spine Society questionnaire for Italian-speaking patients with lumbar spinal disease

STUDY DESIGN: A cross-cultural adaptation and cross-sectional study of a sample of lumbar spine patients, with a subsample followed prospectively for retest reliability. OBJECTIVES: To assess the Italian version instrument reliability and validity. SUMMARY OF BACKGROUND DATA: The orthopaedic outcome measurements have been usually focused on objective parameters as radiograph measures or other technical aspects. However, these parameters are weakly related with outcomes that are more relevant to patients as functional status and symptoms. In the last ten years, the patient-oriented measures have become an important aspect of spinal clinical outcome evaluation. The most common instruments to assess patient perspective are self-administered questionnaires that must be validated by a widely accepted process to evaluate reliability and validity, which are fundamental for every instrumental measure. METHODS: The North American Spine Society (NASS) questionnaire was culturally adapted for Italian-speaking people following the Guillemin criteria. The Italian version was tested on 74 consecutive patients who were referred to the authors' department and suffered from low back pain with leg irradiation. The results were compared with other validated patient-oriented measures. Forty-eight-hour retests were performed on a subsample of 45 patients. RESULTS: The questionnaire was favorably accepted by patients. The lumbar spine pain and disability and neurogenic symptoms subscales showed a high correlation with other patient-oriented measures, as hypothesized, and it also showed good values on test-retest. CONCLUSIONS: The questionnaire should be considered for patient health status monitoring and for clinical trials.     

Spinal tumours: recommendations of the Polish Society of Spine Surgery,the Polish Society of Oncology,the Polish Society of Neurosurgeons,the Polish Society of Oncologic Surgery,the Polish Society of Oncologic Radiotherapy,and the Polish Society of Orthopaedics and Traumatology

Purpose

The purpose of these recommendations is to spread the available evidence for evaluating and managing spinal tumours among clinicians who encounter such entities.

Methods

The recommendations were developed by members of the Development Recommendations Group representing seven stakeholder scientific societies and organizations of specialists involved in various forms of care for patients with spinal tumours in Poland. The recommendations are based on data yielded from systematic reviews of the literature identified through electronic database searches. The strength of the recommendations was graded according to the North American Spine Society’s grades of recommendation for summaries or reviews of studies.

Results

The recommendation group developed 89 level A-C recommendations and a supplementary list of institutions able to manage primary malignant spinal tumours, namely, spinal sarcomas, at the expert level. This list, further called an appendix, helps clinicians who encounter spinal tumours refer patients with suspected spinal sarcoma or chordoma for pathological diagnosis, surgery and radiosurgery. The list constitutes a basis of the network of expertise for the management of primary malignant spinal tumours and should be understood as a communication network of specialists involved in the care of primary spinal malignancies.

Conclusion

The developed recommendations together with the national network of expertise should optimize the management of patients with spinal tumours, especially rare malignancies, and optimize their referral and allocation within the Polish national health service system.

     

Discrepancies in spine surgeon conflict of interest disclosures between a national meeting and physician payment listings on device manufacturer web sites

Background contextPrevious studies have identified inconsistencies in physician conflict-of-interest disclosures at academic meetings. The Physician Payment Sunshine Act (PPSA) will require industry to disclose anything of value given to physicians by 2014. In preparation, some spine device companies have begun reporting payments online.PurposeTo evaluate potential inconsistencies between physician disclosures and payments reported by industry before the PPSA implementation.Study designComparison of publically available disclosure/payment data.Patient samplePhysicians participating in the 2011 North American Spine Society (NASS) annual meeting and physicians listed on the 2010 physician payment web sites of Medtronic and Depuy Spine.MethodsDisclosures of participants at NASS were compared with the published Medtronic and Depuy Spine physician payments. The periods reflected by the disclosures compared should have coincided (except the Depuy site, which was only listed for one quarter of the NASS disclosure period). Discrepancies were noted whenever participant disclosures and company listings did not match as well as whenever payment ranges did not overlap. Fisher's exact test was used to compare disclosure discrepancy rates based on Medtronic payment size. No funding was received for this work. The authors report no conflicts of interest directly related to this study; however, one of the authors does do consulting unrelated to this study.ResultsMedtronic and Depuy Spine were disclosed by 12.1% and 8.75% of NASS participants, respectively. Based on NASS disclosures, 52.4% of NASS participants affiliated with Medtronic had their disclosures inaccurately reflected on the Medtronic web site. Based on Medtronic payment postings, 45.7% of NASS participants listed on Medtronic's webpage had discrepancies in their NASS disclosures. Those who received payments <$100,000 from Medtronic were more likely to have discrepancies in their disclosures than those who received payments >$100,000 (p=.009). Based on Depuy Spine payment postings, 30% of NASS participants listed on Depuy Spine's site had discrepancies in their NASS disclosures.ConclusionsDiscrepancy rates between what spine surgeons disclosed at NASS 2011 and what companies reported for their consultants were high. This is concerning given the passage of the PPSA as well as the increased public visibility of potential discrepancies. More uniform practices will certainly be necessary.     

Reoperation after microdiscectomy of lumbar herniation: Case report

IntroductionAnnuloplasty is the modern pathogenetically substantiated surgical technique for managing lumbar disc herniation that improves the outcomes of limited microdiscectomy. Nevertheless, the rare complications require using a special strategy for managing and customizing treatment and reoperation.Presentation of caseWe present a clinical case of a patient with transpedicular and interbody fixation reoperation after annuloplasty with Barricaid closure device. The aim of this article is to demonstrate the opportunities of surgical treatment of patients with lumbar disc herniation involving annuloplasty using the Barricaid closure device as the final stage and the ways to resolve possible complications requiring reoperation.DiscussionSearching for the most effective methods for preventing recurrent disc herniation is far from being completed; the need for improving methods and techniques of surgical treatment of this pathology is still topical. Reconstruction of the fibrous ring defect is currently one of the promising areas in preventing recurrent lumbar disc herniation.ConclusionElimination of rare complications that have emerged after using the Barricaid annular closure device and require reoperation is possible and has satisfactory outcome.     

The Twin Spine Study: Contributions to a changing view of disc degeneration

Background contextDisc degeneration was commonly viewed over much of the last century as a result of aging and “wear and tear” from mechanical insults and injuries. Thus, prevention strategies and research in lumbar degenerative changes and associated clinical conditions focused largely on mechanical factors as primary causes using an “injury model.” The Twin Spine Study, a research program on the etiology and pathogenesis of disc degeneration, has contributed to a substantial revision of this view of determinants of lumbar disc degeneration.PurposeTo provide a review of the methods and findings of the Twin Spine Study project.Study design/settingNarrative review of the Twin Spine Study.MethodsThe Twin Spine Study, which started in 1991, is a multidisciplinary, multinational research project with collaborators primarily in Canada, Finland, and the United States. The most significant investigations related to determinants of disc degeneration included occupational exposures, driving and whole-body vibration exposure, smoking exposure, anthropomorphic factors, heritability, and the identification of genotypes associated with disc degeneration.ResultsAmong the most significant findings were a substantial influence of heredity on lumbar disc degeneration and the identification of the first gene forms associated with disc degeneration. Conversely, despite extraordinary discordance between twin siblings in occupational and leisure-time physical loading conditions throughout adulthood, surprisingly little effect on disc degeneration was observed. Studies on the effects of smoking on twins with large discordance in smoking exposure demonstrated an increase in disc degeneration associated with smoking, but this effect was small. No evidence was found to suggest that exposure to whole-body vibration through motorized vehicles leads to accelerated disc degeneration in these well-controlled studies. More recent results indicate that the effect of anthropometric factors, such as body weight and muscle strength on disc degeneration, although modest, appear in this work to be greater than those of occupational physical demands. In fact, some indications were found that routine loading may actually have some benefits to the disc.ConclusionsThe once commonly held view that disc degeneration is primarily a result of aging and “wear and tear” from mechanical insults and injuries was not supported by this series of studies. Instead, disc degeneration appears to be determined in great part by genetic influences. Although environmental factors also play a role, it is not primarily through routine physical loading exposures (eg, heavy vs. light physical demands) as once suspected.     

腰椎棘突间稳定器(Wallis)早期疗效分析

目的评价棘突间动力稳定器(Wallis)治疗腰椎退行性疾病的即时(出院前)和短期效果,探讨其适应证选择和手术技巧。方法2008年7月～2009年7月,36例腰椎退行性疾病患者共植入Wallis38套(L2/31套,L3/44套,L4/533套)。其中腰椎间盘脱出症(中央型)8例,腰椎盘脱出伴突出2例,腰椎间盘突出症伴黄韧带增厚10例,腰椎间盘突出症伴侧隐窝狭窄8例,单节退变性椎管狭窄症4例,Topping off4例。采用北美脊柱学会(North American Spine Society,NASS)问卷评价出院前患者及随访患者对手术的满意度,同时测量手术前后椎间盘终板间高度。结果手术时间30～90min,平均60min;术中出血量10～100ml,平均50ml。出院前NASS问卷显示,32例患者(88.9%)认为腰部坚实有力,术前酸乏症状消失或明显减轻。术前终板间高度降低的37个椎间盘中有31个(84%)获得1～3mm的改善。36例患者均获随访,随访时间1～12个月,平均7个月。随访期间NASS问卷总满意度为92.5%,未出现Wallis引起的并发症。结论Wallis的即时和近期疗效满意,是治疗腰椎退变性疾病的有效方法。     

Antibiotic prophylaxis in spine surgery: an evidence-based clinical guideline for the use of prophylactic antibiotics in spine surgery

Background ContextThe objective of the North American Spine Society's (NASS) Evidence-Based Clinical Guideline on Antibiotic Prophylaxis in Spine Surgery is to provide evidence-based recommendations on key clinical questions concerning the use of prophylactic antibiotics in spine surgery. The guideline is intended to address these questions based on the highest quality clinical literature available on this subject as of December 2006. The goal of the guideline recommendations is to assist in delivering optimum, efficacious treatment to prevent surgical site infection.PurposeTo provide an evidence-based, educational tool to assist spine surgeons in preventing surgical site infections.Study DesignEvidence-based Clinical Guideline.MethodsThis report is from the Antibiotic Prophylaxis Work Group of the NASS's Evidence-Based Clinical Guideline Development Committee. The work group comprised multidisciplinary surgical spine care specialists, who were trained in the principles of evidence-based analysis. Each member of the group formatted a series of clinical questions to be addressed by the group. The final questions agreed upon by the group are the subjects of this report. A literature search addressing each question and using a specific search protocol was performed on English language references found in MEDLINE, EMBASE (Drugs and Pharmacology), and four additional, evidence-based, databases. The relevant literature was then independently rated by at least three reviewers using the NASS–adopted standardized levels of evidence. An evidentiary table was created for each of the questions. Final grades of recommendation for the answer to each clinical question were arrived at via Webcast meetings among members of the work group using standardized grades of recommendation. When Level I to Level IV evidence was insufficient to support a recommendation to answer a specific clinical question, expert consensus was arrived at by the work group through the modified nominal group technique and is clearly identified in the guideline.ResultsEleven clinical questions addressed the efficacy and appropriateness of antibiotic prophylaxis protocols, repeat dosing, discontinuation, wound drains, and special considerations related to the potential impact of comorbidities on antibiotic prophylaxis. The responses to these 11 clinical questions are summarized in this document. The respective recommendations were graded by the strength of the supported literature which was stratified by levels of evidence.ConclusionsA clinical guideline addressing the use of antibiotic prophylaxis in spine surgery has been created using the techniques of evidence-based medicine and the best available evidence. This educational tool will assist spine surgeons in preventing surgical site infections. The entire guideline document, including the evidentiary tables, suggestions for future research, and references, is available electronically at the NASS Web site (www.spine.org) and will remain updated on a timely schedule.