Variation in reported safety of lumbar interbody fusion: influence of industrial sponsorship and other study characteristics

What are the rates and validity of French authors' conflicts of interest disclosures in Orthopaedics & Traumatology: Surgery & Research? Analysis of the year 2017 with comparison versus the Transparence.sante.gouv.fr database

INTRODUCTION

Authors are responsible for their own Disclosure of Interests in submitting to Orthopaedics & Traumatology: Surgery & Research (OTSR). Disclosure may be incomplete or false, by deliberate or unintended omission. Omission may impact the analysis of results or at least the reader's perception of it. The rate of validity of disclosure in OTSR is not known, and we therefore conducted a bibliometric study on articles published in 2017, in order to: 1) determine the proportion of articles in which authors disclose interests; and 2), when interests are disclosed, to assess their validity by comparison against the Transparence.gov.fr database.

HYPOTHESIS

Disclosure rates exceed 75%.

MATERIAL AND METHOD

We analyzed all articles published in OTSR in 2017, and extracted those with at least one French author. We also analyzed data from the Transparence.gouv.fr corporate declaration database, for comparison with the authors' own disclosures in each article. Significant interest was defined by a €1000 threshold, although higher thresholds (>€5000, >€10,000 and >€100,000) were also investigated.

RESULTS

In 2017, 337 articles were published in OTSR, 210 of which had at least 1 French author. Of these, 201 (95.7%) had at least 1 author with significant interest (>€1000) according to the Transparence data. In 189 of these 201 articles (94%), authors had failed to disclose at least 1 direct or indirect conflict of interest. This omission rate fell to 22/45 (48.9%) for more substantial interests, which were more faithfully disclosed. At the €1000 threshold, in only 8/201 articles (4%) did authors disclose all their interests with perfect validity, but this rate increased up to 25/45 (55.5%) at higher thresholds. At the €1000 threshold, 66 of the 201 articles cited the trade-name of interest, resulting in 54/66 (82%) correct disclosure of direct interest; this rate increased up to 25/26 (96%) at higher thresholds.

DISCUSSION

At a threshold of €1000, the rate of complete and valid disclosure was 4% and the rate of omission 94%. At higher thresholds, rates were better, with just 48.9% omission and, above all, 55.5% validity, even if these rates were lower than hypothesized (75%). Authors and editors need to take greater care. Disclosures were often made, but incompletely, and authors need reminding that they must disclose not only interests related to the article in question but also all interests that might directly or indirectly influence their interpretation of the results reported, allowing readers to make up their own minds.

LEVEL OF EVIDENCE

IV; systematic retrospective study.

Existing clinical evidence on the use of cellular bone matrix grafts in spinal fusion: updated systematic review of the literature

OBJECTIVE

Spinal fusion surgery is increasingly common; however, pseudarthrosis remains a common complication affecting as much as 15% of some patient populations. Currently, no clear consensus on the best bone graft materials to use exists. Recent advances have led to the development of cell-infused cellular bone matrices (CBMs), which contain living components such as mesenchymal stem cells (MSCs). Relatively few clinical outcome studies on the use of these grafts exist, although the number of such studies has increased in the last 5 years. In this study, the authors aimed to summarize and critically evaluate the existing clinical evidence on commercially available CBMs in spinal fusion and reported clinical outcomes.

METHODS

The authors performed a systematic search of the MEDLINE and PubMed electronic databases for peer-reviewed, English-language original articles (1970-2020) in which the articles' authors studied the clinical outcomes of CBMs in spinal fusion. The US National Library of Medicine electronic clinical trials database (www.ClinicalTrials.gov) was also searched for relevant ongoing clinical trials.

RESULTS

Twelve published studies of 6 different CBM products met inclusion criteria: 5 studies of Osteocel Plus/Osteocel (n = 354 unique patients), 3 of Trinity Evolution (n = 114), 2 of ViviGen (n = 171), 1 of map3 (n = 41), and 1 of VIA Graft (n = 75). All studies reported high radiographic fusion success rates (range 87%-100%) using these CBMs. However, this literature was overwhelmingly limited to single-center, noncomparative studies. Seven studies disclosed industry funding or conflicts of interest (COIs). There are 4 known trials of ViviGen (3 trials) and Bio4 (1 trial) that are ongoing.

CONCLUSIONS

CBMs are a promising technology with the potential of improving outcome after spinal fusion. However, while the number of studies conducted in humans has tripled since 2014, there is still insufficient evidence in the literature to recommend for or against CBMs relative to cheaper alternative materials. Comparative, multicenter trials and outcome registries free from industry COIs are indicated.

Industry payments to authors of Journal of Shoulder and Elbow Surgery shoulder arthroplasty manuscripts are accurately disclosed by most authors and are not significantly associated with better reported treatment outcomes

BACKGROUND

Author transparency in disclosing potential conflicts of interest when reporting outcomes for shoulder arthroplasty implants is important. Using the Centers for Medicare & Medicaid Services Open Payments Program (OPP) database, we analyzed articles in the Journal of Shoulder and Elbow Surgery to evaluate (1) discrepancies between the stated conflicts of interest and associated payments recorded in the database, (2) the magnitude and types of payments received, and (3) possible relationships between industry financial support and positive study outcomes.

METHODS

Articles reporting clinical outcomes of shoulder arthroplasty from 2016 and 2017 were reviewed. Articles identifying a specific shoulder arthroplasty implant and having at least 1 author based in the United States were included. Payment types, amounts, and sources were extracted from disclosure statements in the manuscript and considered relevant if they were received from the implant manufacturer. Published disclosure statements were compared against the OPP database. Study outcomes demonstrating a clinical benefit were considered "positive." Payments to authors reporting positive outcomes were compared with those reporting nonpositive outcomes.

RESULTS

Implant manufacturers provided $16,051,261 to authors of shoulder arthroplasty publications over a 2-year period. Approximately half of senior authors (46%) received royalty payments, more than 90% of which ($14,910,873; 93%) were reported in disclosure statements. Although authors of articles with positive outcomes received greater payments than those reporting nonpositive outcomes, these differences were not statistically significant.

CONCLUSION

The majority of author disclosure statements accurately reflected the OPP data. Payments were not significantly associated with positive outcomes reported for the specific implant.

Uropathogen Resistance and Antibiotic Prophylaxis: A Meta-analysis

CONTEXT

Limited data exist regarding uropathogen resistance in randomized controlled trials of urinary tract infection (UTI) prevention and antibiotic prophylaxis.

OBJECTIVE

To assess the effect of prophylaxis on developing a multidrug-resistant first recurrent UTI among children with vesicoureteral reflux.

DATA SOURCES

Cochrane Kidney and Transplant Specialized Register through May 25, 2017.

STUDY SELECTION

Randomized controlled trials of patients ≤18 years of age with a history of vesicoureteral reflux being treated with continuous antibiotic prophylaxis compared with no treatment or placebo with available antibiotic sensitivity profiles.

DATA EXTRACTION

Two independent observers abstracted data and assessed quality and validity per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Adjusted meta-analyses were performed by using a mixed-effects logistic regression model.

RESULTS

One thousand two hundred and ninety-nine patients contributed 224 UTIs. Patients treated with prophylaxis were more likely to have a multidrug-resistant infection (33% vs 6%, P < .001) and were more likely to receive broad-spectrum antibiotics (68% vs 49%, P = .004). Those receiving prophylaxis had 6.4 times the odds (95% confidence interval: 2.7-15.6) of developing a multidrug-resistant infection. One multidrug-resistant infection would develop for every 21 reflux patients treated with prophylaxis.

LIMITATIONS

Variables that may contribute to resistance such as medication adherence and antibiotic exposure for other illnesses could not be evaluated.

CONCLUSIONS

Prophylaxis increases the risk of multidrug resistance among recurrent infections. This has important implications in the risk-benefit assessment of prophylaxis as a management strategy and in the selection of empirical treatment of breakthrough infections in prophylaxis patients.

Factors Associated With Financial Relationships Between Spine Surgeons and Industry: An Analysis of the Open Payments Database

STUDY DESIGN

A retrospective review of Centers for Medicare and Medicaid Services Database.

OBJECTIVE

Utilizing Open Payments data, we aimed to determine the prevalence of industry payments to orthopedic and neurospine surgeons, report the magnitude of those relationships, and help outline the surgeon demographic factors associated with industry relationships.

SUMMARY OF BACKGROUND DATA

Previous Open Payments data revealed that orthopedic surgeons receive the highest value of industry payments. No study has investigated the financial relationship between spine surgeons and industry using the most recent release of Open Payments data.

METHODS

A database of 5898 spine surgeons in the United States was derived from the Open Payments website. Demographic data were collected, including the type of residency training, years of experience, practice setting, type of medical degree, place of training, gender, and region of practice. Multivariate generalized linear mixed models were utilized to determine the relationship between demographics and industry payments.

RESULTS

A total of 5898 spine surgeons met inclusion criteria. About 91.6% of surgeons reported at least one financial relationship with industry. The median total value of payments was $994.07. Surgeons receiving over $1,000,000 from industry during the reporting period represented 6.6% of the database and accounted for 83.5% of the total value exchanged. Orthopedic training (P < 0.001), academic practice setting (P < 0.0001), male gender (P < 0.0001), and West or South region of practice (P < 0.0001) were associated with industry payments. Linear regression analysis revealed a strong inverse relationship between years of experience and number of payments from industry (r = -0.967, P < 0.0001).

CONCLUSION

Financial relationships between spine surgeons and industry are highly prevalent. Surgeon demographics have a significant association with industry-surgeon financial relationships. Our reported value of payments did not include ownership or research payments and thus likely underestimates the magnitude of these financial relationships.

LEVEL OF EVIDENCE

3.

Effects of Conflicts of Interest on Practice Patterns and Complication Rates in Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

We sought to determine whether financial relationships with industry had any impact on operative and/or complication rates of spine surgeons performing fusion surgeries.

SUMMARY OF BACKGROUND DATA

Recent actions from Congress and the Institute of Medicine have highlighted the importance of conflicts of interest among physicians. Orthopedic surgeons and neurosurgeons have been identified as receiving the highest amount of industry payments among all specialties. No study has yet investigated the potential effects of disclosed industry payments with quality and choices of patient care.

METHODS

A comprehensive database of spine surgeons in the United States with compiled data of industry payments, operative fusion rates, and complication rates was created. Practice pattern data were derived from a publicly available Medicare-based database generated from selected CPT codes from 2011 to 2012. Complication rate data from 2009 to 2013 were extracted from the ProPublica-Surgeon-Scorecard database, which utilizes postoperative inhospital mortality and 30-day-readmission for designated conditions as complications of surgery. Data regarding industry payments from 2013 to 2014 were derived from the Open Payments website. Surgeons performing <10 fusions, those without complication data, and those whose identity could not be verified through public records were excluded. Pearson correlation coefficients and multivariate regression analyses were used to determine the relationship between industry payments, operative fusion rate, and/or complication rate.

RESULTS

A total of 2110 surgeons met the inclusion criteria for our database. The average operative fusion rate was 8.8% (SD 4.8%), whereas the average complication rate for lumbar and cervical fusion was 4.1% and 1.9%, respectively. Pearson correlation analysis revealed a statistically significant but negligible relationship between disclosed payments/transactions and both operative fusion and complication rates.

CONCLUSION

Our findings do not support a strong correlation between the payments a surgeon receives from industry and their decisions to perform spine fusion or associated complication rates. Large variability in the rate of fusions performed suggests a poor consensus for indications for spine fusion surgery.

LEVEL OF EVIDENCE

3.

Complications Associated With Bone Morphogenetic Protein in the Lumbar Spine

Complications associated with the use of recombinant human bone morphogenetic protein in the lumbar spine include retrograde ejaculation, ectopic bone formation, vertebral osteolysis and subsidence, postoperative radiculitis, and hematoma and seroma. These complications are controversial and remain widely debated. This article discusses the reported complications and possible implications for the practicing spine surgeon. Understanding the complications associated with the use of recombinant human bone morphogenetic protein and the associated controversies allows for informed decision making by both the patient and the surgeon. [Orthopedics. 2017; 40(2):e229-e237.].

Efficacy of antibiotic prophylaxis in children with vesicoureteral reflux: systematic review and meta-analysis

PURPOSE

Controversy exists regarding the use of continuous antibiotic prophylaxis vs observation in the management of children with vesicoureteral reflux. The reported effectiveness of continuous antibiotic prophylaxis in children with reflux varies widely. We determined whether the aggregated evidence supports use of continuous antibiotic prophylaxis in children with vesicoureteral reflux.

MATERIALS AND METHODS

We searched the Cochrane Controlled Trials Register, clinicaltrials.gov, MEDLINE(®), EMBASE(®), Google Scholar and recently presented meeting abstracts for reports in any language. Bibliographies of included studies were then hand searched for any missed articles. The study protocol was prospectively registered at PROSPERO (No. CRD42014009639). Reports were assessed and data abstracted in duplicate, with differences resolved by consensus. Risk of bias was assessed using standardized instruments.

RESULTS

We identified 1,547 studies, of which 8 are included in the meta-analysis. Pooled results demonstrated that continuous antibiotic prophylaxis significantly reduced the risk of recurrent febrile or symptomatic urinary tract infection (pooled OR 0.63, 95% CI 0.42-0.96) but, if urinary tract infection occurred, increased the risk of antibiotic resistant organism (pooled OR 8.75, 95% CI 3.52-21.73). A decrease in new renal scarring was not associated with continuous antibiotic prophylaxis use. Adverse events were similar between the 2 groups. Significant heterogeneity existed between studies (I(2) 50%, p = 0.03), specifically between those trials with significant risk of bias (eg unclear protocol descriptions and/or lack of blinding).

CONCLUSIONS

Compared to no treatment, continuous antibiotic prophylaxis significantly reduced the risk of febrile and symptomatic urinary tract infections in children with vesicoureteral reflux, although it increased the risk of infection due to antibiotic resistant bacteria. Continuous antibiotic prophylaxis did not significantly impact the occurrence of new renal scarring or reported adverse events.

Mitigating adverse event reporting bias in spine surgery

BACKGROUND

Recent articles in the lay press and literature have raised concerns about the ability to report honest adverse event data from industry-sponsored spine surgery studies. To address this, clinical trials may utilize an independent Clinical Events Committee (CEC) to review adverse events and readjudicate the severity and relatedness accordingly. We are aware of no prior study that has quantified either the degree to which investigator bias is present in adverse event reporting or the effect that an independent CEC has on mitigating this potential bias.

METHODS

The coflex Investigational Device Exemption study is a prospective randomized controlled trial comparing coflex (Paradigm Spine) stabilization with lumbar spinal fusion to treat spinal stenosis and spondylolisthesis. Investigators classified the severity of adverse events (mild, moderate, or severe) and their relationship to the surgery and device (unrelated, unlikely, possibly, probably, or definitely). An independent CEC, composed of three spine surgeons without affiliation to the study sponsor, reviewed and reclassified all adverse event reports submitted by the investigators.

RESULTS

The CEC reclassified the level of severity, relation to the surgery, and/or relation to the device in 394 (37.3%) of 1055 reported adverse events. The proportion of adverse events that underwent reclassification was similar in the coflex and fusion groups (37.9% compared with 36.0%, p = 0.56). The CEC was 5.3 (95% confidence interval [CI], 2.6 to 10.7) times more likely to upgrade than downgrade the adverse event. The CEC was 7.3 (95% CI, 5.1 to 10.6) times more likely to upgrade than downgrade the relationship to the surgery and 11.6 (95% CI, 7.5 to 18.8) times more likely to upgrade than downgrade the relationship to the device. The status of the investigator's financial interest in the company had little effect on the reclassification of adverse events.

CONCLUSIONS

Thirty-seven percent of adverse events were reclassified by the CEC; the large majority of the reclassifications were an upgrade in the level of severity or a designation of greater relatedness to the surgery or device.

CLINICAL RELEVANCE

An independent CEC can identify and mitigate potential inherent investigator bias and facilitate an accurate assessment of the safety profile of an investigational device, and a CEC should be considered a requisite component of future clinical trials.

Comparison of patient and surgeon perceptions of adverse events after adult spinal deformity surgery

STUDY DESIGN

Survey based on complication scenarios.

OBJECTIVE

To assess and compare perceived potential impacts of various perioperative adverse events by both surgeons and patients.

SUMMARY OF BACKGROUND DATA

Incidence of adverse events after adult spinal deformity surgery remains substantial. Patient-centered outcomes tools measuring the impact of these events have not been developed. An important first step is to assess the perceptions of surgeons and patients regarding the impact of these events on surgical outcome and quality of life.

METHODS

Descriptions of 22 potential adverse events of surgery (heart attack, stroke, spinal cord injury, nerve root injury, cauda equina injury, blindness, dural tear, blood transfusion, deep vein thrombosis, pulmonary embolism, superficial infection, deep infection, lung failure, urinary tract infection, nonunion, adjacent segment disease, persistent deformity, implant failure, death, renal failure, gastrointestinal complications, and sexual dysfunction) were presented to 14 spinal surgeons and 16 adult patients with spinal deformity. Impact scores were assigned to each complication on the basis of perceptions of overall severity, satisfaction with surgery, and effect on quality of life. Impact scores were compared between surgeons and patients with a Wilcoxon/Kruskal-Wallis test.

RESULTS

Mean impact scores varied from 0.9 (blood transfusion) to 10.0 (death) among surgeons and 2.3 (urinary tract infection) to 9.2 (stroke) among patients. Patients' scores were consistently higher (P < 0.05) than surgeons in all 3 categories for 6 potential adverse events: stroke, lung failure, heart attack, pulmonary embolism, dural tear, and blood transfusion. Three additional complications (renal failure, non-union, and deep vein thrombosis) were rated higher in 1 or 2 categories by patients.

CONCLUSION

There was substantial variation in how both surgeons and patients perceived impacts of various adverse events after spine surgery. Patients generally perceived the impact of adverse events to be greater than surgeons. Patient-centered descriptions of adverse events would provide a more complete description of surgical outcomes.

Retrograde ejaculation after anterior lumbar interbody fusion with and without bone morphogenetic protein-2 augmentation: a 10-year cohort controlled study

BACKGROUND CONTEXT

Retrograde ejaculation (RE) is a complication of anterior lumbar interbody fusion (ALIF) techniques. Most commonly, this results from mechanical or inflammatory injury to the superior hypogastric plexus near the aortic bifurcation. Bone morphogenetic protein-2 (BMP-2) has been used in spinal fusions and has been associated with inflammatory and neuroinflammatory adverse reactions, which may contribute to RE development after anterior lumbar surgery.

PURPOSE

While controlling for anterior approach technique, we compared the incidence of RE with and without rhBMP-2 exposure, in large, matched cohorts of patients after ALIF.

STUDY DESIGN

Retrospective analysis of 10 years of prospectively gathered outcomes data on consecutive-patient cohorts having the same anterior exposure technique for ALIF with and without rhBMP-2 use.

PATIENT SAMPLE

All male patients without baseline sexual incapacity and having ALIF for lumbar spondylosis or spondylolisthesis of the lowest one or two lumbar levels with and without rhBMP-2, from 2002 through 2011.

OUTCOME MEASURES

Diagnosis of RE as a new finding after ALIF compared against BMP-2 exposure, comorbid conditions, and other urological complications after ALIF surgery.

METHODS

From the comprehensive surgical database at a high volume, university practice, male subjects having ALIF at one (L5/S1) or two levels (L4/5, L5/S1) from 2002 to 2011 were identified. Baseline comorbid factors, postoperative urinary catheter/retention events, and RE events were recorded and comparative incidence compared.

RESULTS

There were four consecutive-patient cohorts identified: one before rhBMP-2 use was adopted (n=174), two cohorts in which BMP-2 use was routine (n=88 and n=151), and one final cohort after BMP-2 use was discontinued from routine use (n=59). The cohorts with and without BMP-2 exposure were closely comparable for age, approach, levels of surgery, comorbid factors affecting RE. Of 239 patients with ALIF and exposure to BMP-2, RE was diagnosed in 15 subjects (6.3%), compared with an RE diagnosis rate of two of 233 control patients without BMP-2 exposure (0.9%; p=.0012). Urinary retention after bladder catheter removal was also more frequently observed in patients exposed to BMP-2 (9.7%) compared with control patients (4.6%; p=.043). Of the baseline comorbid factors, medical or surgical treatment for prostatic hypertrophy disease was associated with an increased risk of RE in the BMP-2 patients (p=.034).

CONCLUSIONS

This study confirms previous reports of a higher rate of RE in ALIF procedures using rhBMP-2 and an open anterior approach to the spine. This effect may be associated with an increased risk of postoperative urinary retention after BMP-2 exposure. The magnitude of the RE effect may be increased with concomitant prostatic disease treatments.

Retrograde ejaculation after anterior lumbar interbody fusion using rhBMP-2: a cohort controlled study

BACKGROUND CONTEXT

The commercially available growth factor recombinant bone morphogenic protein-2 (rhBMP-2) used in spinal fusion has been associated with numerous adverse reactions, including inflammatory reactions in soft tissue, heterotopic bone formation, radiculitis, osteolysis, and cage or graft subsidence. The original Food and Drug Administration Summary of anterior lumbar interbody fusion (ALIF) reported 12 retrograde ejaculation (RE) events (8%) in the rhBMP-2 groups compared with (1.4%) in the control group. It had been debated whether this finding was related to rhBMP-2 use.

PURPOSE

To compare the incidence of RE after ALIF in patients with and without rhBMP-2 use.

STUDY DESIGN

Retrospective analysis of prospectively gathered outcomes data on consecutive subjects having ALIF with and without rhBMP-2 use.

PATIENT SAMPLE

Male patients with lumbar spondylosis or spondylolisthesis having ALIF of the lowest one or two lumbar levels with and without rhBMP-2.

OUTCOME MEASURE

Report of RE as a new finding after ALIF.

METHODS

From the comprehensive outcome database at a high-volume university practice, male subjects having ALIF for one- (L5/S1) or two-level (L4/L5, L5/S1) lumbar fusion were identified. Retrograde ejaculation events were recorded and comparative incidence compared.

RESULTS

The two groups were comparable for age and additional procedures performed. There were 69 L5/S1 ALIFs performed with rhBMP-2 and 174 ALIFs performed without rhBMP-2 during the study period. Of those, 24 and 64 were two-level ALIFs performed with and without rhBMP-2, respectively. There were five RE events (7.2%) reported in the rhBMP-2 group and 1 (0.6%) in the control group. Comparing single-level L5/S1 ALIF, there was a 6.7% and 0% rate of RE in the rhBMP-2 versus control groups, respectively. At 1 year after surgery, three of six affected subjects reported resolution of the RE.

CONCLUSION

This study confirms previous reports of a higher rate of RE in ALIF procedures using rhBMP-2. This may be an important consideration in subjects concerned with sterility after surgery.

Dextranomer/hyaluronic acid for pediatric vesicoureteral reflux: systematic review

OBJECTIVE

Published success rates of dextranomer/hyaluronic acid (Dx/HA) injection for pediatric vesicoureteral reflux (VUR) vary widely. Our objective of this study was to assess whether underlying patient or study factors could explain the heterogeneity in reported Dx/HA success rates.

METHODS

We searched the Cochrane Controlled Trials Register and Medline, Embase, and Scopus databases from 1990 to 2008 for reports in any language, along with a hand search of included study bibliographies. Articles were assessed and data abstracted in duplicate, and differences were resolved by consensus. Conflict of interest (COI) was determined by published disclosure. Meta-regression was performed to adjust for patient as well as study-level factors.

RESULTS

We identified 1157 reports, 89 of which were reviewed in full with 47 included in the pooled analysis. Of 7303 ureters that were injected with Dx/HA, 5633 (77%) were successfully treated according to the authors' definition. Injection success seemed to vary primarily on the basis of the preoperative reflux grade. After adjustment for VUR grade, other factors, such as the presence or absence of COI disclosure, were not significant. Studies were markedly heterogeneous overall.

CONCLUSIONS

The overall per-ureter Dx/HA success rate was 77% after 3 months, although success rates varied widely among studies. Increased VUR grade negatively affected success rates, whereas COI, patient age, and injected Dx/HA volume were not significantly associated with treatment outcome after adjustment for VUR grade. There is a significant need for improved reporting of VUR treatments, including comparative studies of Dx/HA and other VUR treatments.

Methods for the systematic reviews on patient safety during spine surgery

STUDY DESIGN

Systematic review.

OBJECTIVE

To provide a detailed description of the methods undertaken in the systematic search and analytical summary of patient safety issues in spinal surgery, and to describe the process used to come to a clinical recommendation regarding challenges in the management of patients undergoing spine surgery.

SUMMARY OF BACKGROUND DATA

A solid understanding of complication type, incidence, risk factors, and impact is implicit to the physician's role in developing an informed patient centered decision with respect to surgical intervention. We present methods used in conducting the systematic, evidence-based reviews, and expert panel recommendations of key challenges to the spine surgical practice. It is our desire that spine surgeons will use the information from these reviews together with an understanding of their own capacities and experience to better inform patients with respect to potential treatment outcomes, safety, and life impact.

METHODS

A systematic search and critical review of the English language literature was undertaken for articles published on the safety of various surgical spine conditions. Citations were screened for relevance using a priori criteria, and relevant studies were critically reviewed. The strength of evidence for the overall body of literature in each topic area was determined by 2 independent reviewers considering study quality, study quantity, and consistency of results. Disagreements were resolved by consensus. Findings from studies meeting inclusion criteria were summarized. From these summaries, clinical recommendations were formulated from consensus achieved among subject experts through the Delphi process.

RESULTS

We identified and screened 2020 citations in 13 topic areas relating to safety in spine surgery. Of these, 273 met our predetermined inclusion criteria and were used to attempt to answer specific clinical questions within each topic area.

CONCLUSION

We undertook systematic reviews to establish a baseline of the current evidence on patient safety issues in spine surgery. This article reports the methods used in the reviews.

Fusion versus disk replacement for degenerative conditions of the lumbar and cervical spine: quid est testimonium?

This article compares the outcomes following spinal fusion and disk replacement for degenerative conditions of the lumbar and cervical spine. The short-term outcomes of lumbar and cervical total disk replacement are equivalent to that following spinal fusion. Long-term follow-up studies of total disk replacement are necessary to confirm its potential benefit in reducing or preventing adjacent level degeneration. Also discussed is the philosophy of the surgical management of degenerative conditions of the lumbar and cervical spine.

Accuracy of conflict-of-interest disclosures reported by physicians

BACKGROUND

The recent public reporting of payments made to physicians by manufacturers of orthopedic devices provides an opportunity to assess the accuracy of physicians' conflict-of-interest disclosures.

METHODS

We analyzed the reports of payments made to physicians by five manufacturers of total hip and knee prostheses in 2007. For each payment recipient who was an author of a presentation or served as a committee member or board member at the 2008 annual meeting of the American Academy of Orthopaedic Surgeons, the disclosure statement was reviewed to determine whether the payment had been disclosed. To ascertain the reasons for nondisclosure, a survey was administered to physicians who had received payments that were not disclosed.

RESULTS

The overall rate of disclosure was 71.2% (245 of 344 payments). For payments that were directly related to the topic of the presentation at the meeting, the rate was 79.3% (165 of 208); for payments that were indirectly related, the rate was 50.0% (16 of 32); and for payments that were unrelated, the rate was 49.2% (29 of 59) (P=0.008). In the multivariate analysis, payments were also more likely to have been disclosed if they exceeded $10,000 (P<0.001), were directed toward an individual physician rather than a company or organization (P=0.04), or included an in-kind component (P=0.002). Among the 36 physicians who responded to the survey regarding reasons for nondisclosure (response rate, 39.6%), the reasons most commonly given for nondisclosure were that the payment was unrelated to the topic of presentation at the annual meeting (38.9% of respondents) and that the physician had misunderstood the disclosure requirements (13.9%); 11.1% reported that the payment had been disclosed but was mistakenly omitted from the program.

CONCLUSIONS

In this study of self-reported conflict-of-interest disclosure by physicians at a large annual meeting, the rate of disclosure was 79.3% for directly related payments and 50.0% for indirectly related payments.

National complication rates and disposition after posterior lumbar fusion for acquired spondylolisthesis

STUDY DESIGN

Database study using Nationwide Inpatient Sample (NIS) administrative data from 1993 to 2002.

OBJECTIVE

To determine rates of in-hospital complications and complex disposition for patients undergoing posterior lumbar fusion for degenerative spondylolisthesis, and the association of demographic factors.

SUMMARY OF BACKGROUND DATA

Spondylolisthesis affects primarily elderly populations. Recent data suggests a benefit of surgical treatment for acquired lumbar spondylolisthesis. However, the risks of these procedures, and the impact of patient demographics on risk, have not been nationally quantified.

METHODS

Data from 66,601 patients in the NIS (1993-2002) with diagnostic and procedure codes specifying posterior lumbar fusion for acquired spondylolisthesis were included. Patients were grouped by age, sex, race, number of comorbidities, hospital size, and time period of procedure. Multivariate analysis correlated patient and hospital characteristics with complex disposition and complications.

RESULTS

Mortality rate was 0.15%. Eleven percent of patients had one or more in-hospital complications; overall complication rate was 13 per 100 operations. Hematoma/seroma (5.4 per 100) was the most common complication, followed by pulmonary (2.6), renal (1.8), and cardiac (1.2) complications. Infection and neurologic injury occurred in <1% of patients. Older patients and those with a number of comorbidities had greater rates of in-hospital complication and complex disposition. Compared to those aged 45 to 64, patients aged 65 to 84 were almost 70% more likely to have complications (OR: 1.67) and 5 times as likely to have complex disposition (OR: 5.84). Having 3 or greater comorbidities, compared to no comorbidities, was also associated with increased risk of complication (OR: 1.6) and complex disposition (OR: 2.3).

CONCLUSION

Posterior lumbar fusion for acquired lumbar spondylolisthesis is safe. However, age and comorbidity independently increase in-hospital complications and complex disposition. These data may improve national estimates of surgical risk, patient selection, informed consent, and cost-efficacy analysis for posterior lumbar fusion operations for acquired spondylolisthesis.

Surgery for low back pain: a review of the evidence for an American Pain Society Clinical Practice Guideline

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically assess benefits and harms of surgery for nonradicular back pain with common degenerative changes, radiculopathy with herniated lumbar disc, and symptomatic spinal stenosis.

SUMMARY OF BACKGROUND DATA

Although back surgery rates continue to increase, there is uncertainty or controversy about utility of back surgery for various conditions.

METHODS

Electronic database searches on Ovid MEDLINE and the Cochrane databases were conducted through July 2008 to identify randomized controlled trials and systematic reviews of the above therapies. All relevant studies were methodologically assessed by 2 independent reviewers using criteria developed by the Cochrane Back Review Group (for trials) and Oxman (for systematic reviews). A qualitative synthesis of results was performed using methods adapted from the US Preventive Services Task Force.

RESULTS

For nonradicular low back pain with common degenerative changes, we found fair evidence that fusion is no better than intensive rehabilitation with a cognitive-behavioral emphasis for improvement in pain or function, but slightly to moderately superior to standard (nonintensive) nonsurgical therapy. Less than half of patients experience optimal outcomes (defined as no more than sporadic pain, slight restriction of function, and occasional analgesics) following fusion. Clinical benefits of instrumented versus noninstrumented fusion are unclear. For radiculopathy with herniated lumbar disc, we found good evidence that standard open discectomy and microdiscectomy are moderately superior to nonsurgical therapy for improvement in pain and function through 2 to 3 months. For symptomatic spinal stenosis with or without degenerative spondylolisthesis, we found good evidence that decompressive surgery is moderately superior to nonsurgical therapy through 1 to 2 years. For both conditions, patients on average experience improvement either with or without surgery, and benefits associated with surgery decrease with long-term follow-up in some trials. Although there is fair evidence that artificial disc replacement is similarly effective compared to fusion for single level degenerative disc disease and that an interspinous spacer device is superior to nonsurgical therapy for 1- or 2-level spinal stenosis with symptoms relieved with forward flexion, insufficient evidence exists to judge long-term benefits or harms.

CONCLUSION

Surgery for radiculopathy with herniated lumbar disc and symptomatic spinal stenosis is associated with short-term benefits compared to nonsurgical therapy, though benefits diminish with long-term follow-up in some trials. For nonradicular back pain with common degenerative changes, fusion is no more effective than intensive rehabilitation, but associated with small to moderate benefits compared to standard nonsurgical therapy.

Mortality after lumbar fusion surgery

STUDY DESIGN

Retrospective population-based cohort study.

OBJECTIVE

To describe mortality after lumbar fusion surgery in Washington State workers' compensation claimants in the perioperative period and beyond.

SUMMARY OF BACKGROUND DATA

Although lumbar fusion surgery can be associated with serious complications, perioperative mortality is generally considered rare. Population-based mortality estimates have been limited to surgery in older adults.

METHODS

We identified all Washington State workers' compensation claimants who underwent fusion between January 1994 and December 2001 (n = 2378) and assessed the frequency, timing, and causes of death. Mortality follow-up was concluded in 2004. Death was ascertained from Washington State vital statistics records and from the workers' compensation claims database. Poisson regression was used to obtain age- and gender-adjusted mortality rates. Years of potential life lost, percent of potential life lost, and mean potential life lost were calculated for the leading 5 causes of death and we calculated the risk of death associated with selected predictors.

RESULTS

Among the 2378 lumbar fusion subjects in the study cohort, 103 were deceased by 2004. The 3-year cumulative mortality rate was 1.93% (95% confidence interval, 1.41%-2.57%). The 90-day perioperative mortality rate was 0.29% (95% confidence interval, 0.11%-0.60%). The risk of perioperative mortality was positively associated with repeat fusions. The age- and gender-adjusted all-cause mortality rate was 3.1 deaths per 1000 worker-years (95% confidence interval, 0.9-9.8). Analgesic-related deaths were responsible for 21% of all deaths and 31.4% of all potential life lost. The risk of analgesic-related death was higher among workers who received instrumentation or intervertebral cage devices compared with recipients of bone-only fusions (1.1% vs. 0.0%; P = 0.03) and among workers with degenerative disc disease (age- and gender-adjusted mortality rate ratio, 2.71) (95% confidence interval, 1.17-6.28). The burden was especially high among subjects between 45 and 54 years old with degenerative disc disease (rate ratio, 7.45).

CONCLUSION

Analgesic-related deaths are responsible for more deaths and more potential life lost among workers who underwent lumbar fusion than any other cause. Risk of analgesic-related death was especially high among young and middle-aged workers with degenerative disc disease.

Outcome of lumbar arthrodesis in patients sixty-five years of age or older

BACKGROUND

The value of lumbar spine arthrodesis in older patients is not well documented. As most of the literature regarding lumbar arthrodesis in older patients has focused on the prevalence of complications, the purpose of this study was to determine the clinical outcomes for older compared with younger patients undergoing lumbar arthrodesis.

METHODS

We studied 224 patients who underwent a single-level posterolateral lumbar arthrodesis with an iliac crest bone graft. Outcome measures included the Oswestry Disability Index, the Medical Outcomes Study Short Form-36 and numeric rating scales for back and leg pain, as well as a radiographic assessment of fusion. Outcome measures were evaluated on the basis of the mean change and the percentage of patients reaching a minimum clinically important difference threshold. For comparison, the patients were divided into two groups: 174 patients who were younger than sixty-five years and fifty patients who were sixty-five years of age or older.

RESULTS

Substantial improvements from baseline were noted in all of the clinical and health-related quality-of-life measures at the six-month, one-year, and two-year intervals. The mean improvements in the Oswestry Disability Index score at two years postoperatively were 28.5 points for the older patients and 24.5 points for the younger patients. For Short Form-36 physical component summary scores, the mean improvement from baseline was 14.2 points for the older group and 11.7 points for the younger group at two years. The older patients also demonstrated a similar or greater improvement in the numeric rating scale back and leg pain scores at all time intervals, with a significant difference in leg pain scores at two years postoperatively (10.4 points for the older patients and 6.4 points for the younger patients; p=0.002). Perioperative complications, although an obvious concern, did not appear to adversely affect clinical and health-related quality-of-life outcomes at two years postoperatively.

CONCLUSIONS

This study demonstrates a substantial benefit for patients sixty-five years of age or older with degenerative disc disease who are treated with a single-level lumbar decompression and instrumented arthrodesis, and we conclude that lumbar arthrodesis is a viable and reasonable treatment option for appropriately selected patients sixty-five years of age or older.

Treatment of neck pain: injections and surgical interventions: results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders

STUDY DESIGN

Best evidence synthesis.

OBJECTIVE

To identify, critically appraise, and synthesize literature from 1980 through 2006 on surgical interventions for neck pain alone or with radicular pain in the absence of serious pathologic disease.

SUMMARY OF BACKGROUND DATA

There have been no comprehensive systematic literature or evidence-based reviews published on this topic.

METHODS

We systematically searched Medline for literature published from 1980 to 2006 on percutaneous and open surgical interventions for neck pain. Publications on the topic were also solicited from experts in the field. Consensus decisions were made about the scientific merit of each article; those judged to have adequate internal validity were included in our Best Evidence Synthesis.

RESULTS

Of the 31,878 articles screened, 1203 studies were relevant to the Neck Pain Task Force mandate and of these, 31 regarding treatment by surgery or injections were accepted as scientifically admissible. Radiofrequency neurotomy, cervical facet injections, cervical fusion and cervical arthroplasty for neck pain without radiculopathy are not supported by current evidence. We found there is support for short-term symptomatic improvement of radicular symptoms with epidural corticosteroids. It is not clear from the evidence that long-term outcomes are improved with the surgical treatment of cervical radiculopathy compared to nonoperative measures. However, relatively rapid and substantial symptomatic relief after surgical treatment seems to be reliably achieved. It is not evident that one open surgical technique is clearly superior to others for radiculopathy. Cervical foramenal or epidural injections are associated with relatively frequent minor adverse events (5%-20%); however, serious adverse events are very uncommon (<1%). After open surgical procedures on the cervical spine, potentially serious acute complications are seen in approximately 4% of patients.

CONCLUSION

Surgical treatment and limited injection procedures for cervical radicular symptoms may be reasonably considered in patients with severe impairments. Percutaneous and open surgical treatment for neck pain alone, without radicular symptoms or clear serious pathology, seems to lack scientific support.

Industry-sponsored research

Financial conflicts of interest are exceedingly common in biomedical research. Investigators with conflicts of interest are more likely to arrive at positive conclusions, perhaps as a result of biased study design, industry suppression of negative results, preferential funding by industry of projects that are likely to succeed, or biased interpretation of results on the part of investigators. Government and professional organisations have proposed guidelines for managing conflicts of interest, but in practice it is the policies of universities and medical journals that direct the actions of investigators. Academic researchers and the media have expressed concern about the influence of industry sponsorship on biomedical research, while industry is increasingly turning to private entities (such as contract research organisations) to conduct clinical trials. Research participants appear less concerned with conflicts of interest in biomedical research, perhaps due to a faith that such conflicts are being appropriately managed by institutions. After reviewing the literature, we provide recommendations for the ethical conduct of biomedical research in the presence of financial conflicts of interest.

Treatment of neck pain: injections and surgical interventions: results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders

STUDY DESIGN

Best evidence synthesis.

OBJECTIVE

To identify, critically appraise, and synthesize literature from 1980 through 2006 on surgical interventions for neck pain alone or with radicular pain in the absence of serious pathologic disease.

SUMMARY OF BACKGROUND DATA

There have been no comprehensive systematic literature or evidence-based reviews published on this topic.

METHODS

We systematically searched Medline for literature published from 1980 to 2006 on percutaneous and open surgical interventions for neck pain. Publications on the topic were also solicited from experts in the field. Consensus decisions were made about the scientific merit of each article; those judged to have adequate internal validity were included in our Best Evidence Synthesis.

RESULTS

Of the 31,878 articles screened, 1203 studies were relevant to the Neck Pain Task Force mandate and of these, 31 regarding treatment by surgery or injections were accepted as scientifically admissible. Radiofrequency neurotomy, cervical facet injections, cervical fusion and cervical arthroplasty for neck pain without radiculopathy are not supported by current evidence. We found there is support for short-term symptomatic improvement of radicular symptoms with epidural corticosteroids. It is not clear from the evidence that long-term outcomes are improved with the surgical treatment of cervical radiculopathy compared to nonoperative measures. However, relatively rapid and substantial symptomatic relief after surgical treatment seems to be reliably achieved. It is not evident that one open surgical technique is clearly superior to others for radiculopathy. Cervical foramenal or epidural injections are associated with relatively frequent minor adverse events (5%-20%); however, serious adverse events are very uncommon (<1%). After open surgical procedures on the cervical spine, potentially serious acute complications are seen in approximately 4% of patients.

CONCLUSION

Surgical treatment and limited injection procedures for cervical radicular symptoms may be reasonably considered in patients with severe impairments. Percutaneous and open surgical treatment for neck pain alone, without radicular symptoms or clear serious pathology, seems to lack scientific support.