Review of mechanisms of expandable spine surgery devices.

INTRODUCTION: Expandable devices such as interbody cages, vertebral body reconstruction cages, and intravertebral body expansion devices are frequently utilized in spine surgery. Since the introduction of expandable implants in the early 2000s, the variety of mechanisms that drive expansion and implant materials have steadily increased. By examining expandable devices that have achieved commercial success and exploring emerging innovations, we aim to offer an in-depth evaluation of the different types of expandable cages used in spine surgery and the underlying mechanisms that drive their functionality. AREAS COVERED: We performed a review of expandable spinal implants and devices by querying the National Library of Medicine MEDLINE database and Google Patents database from 1933 to 2024. Five major types of mechanical jacks that drive expansion were identified: scissor, pneumatic, screw, ratchet, and insertion-expansion. EXPERT OPINION: We identified a trend of screw jack mechanism being the predominant machinery in vertebral body reconstruction cages and scissor jack mechanism predominating in interbody cages. Pneumatic jacks were most commonly found in kyphoplasty devices. Critically reviewing the mechanisms of expansion and identifying trends among effective and successful cages allows both surgeons and medical device companies to properly identify future areas of development.

Presence of Cerebrospinal Fluid on Preoperative Imaging and the Associated Cervical Myelopathy Diagnosis and Outcome.

STUDY DESIGN: Retrospective chart review. OBJECTIVE: The objective of this study is to determine whether the presence of cerebrospinal fluid is associated with the severity of degenerative cervical myelopathy or postoperative outcomes. SUMMARY OF BACKGROUND DATA: Degenerative cervical myelopathy (DCM) is a clinical diagnosis characterized as neurologic dysfunction. Preoperative imaging is used to determine the source of cord compression. In clinical practice, cerebrospinal fluid (CSF) around the cord is often used as an indicator to determine whether stenosis is relevant. It is unclear if the presence of CSF around the cord can serve as a metric for clinically relevant cord compression. METHODS: Patients undergoing single-level anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy were identified from our institution's surgical database. Pre- and postoperative patient-reported health outcomes visual analog scale for neck pain (VAS-NP) and modified Japanese Orthopaedic Association (mJOA) were collected. The level of ACDF plus one level above and below were assessed for the presence of cerebrospinal fluid, as well as measuring the area of the spinal canal and spinal cord on preoperative magnetic resonance imaging. RESULTS: Two hundred forty-nine patients were included. Spearman correlation test comparing cord/canal ratios at the level of compression and preoperative mJOA shows a significant negative correlation (Rho = -0.206, P= 0.043). There was no significant correlation with postoperative change in mJOA scores (Rho = -0.002, P= 0.986). CONCLUSION: The presence of CSF around the cord was weakly correlated with the severity of myelopathy; however, it had no correlation with postoperative outcomes. The presence of CSF around the cord should not in isolation be used to rule in or rule out operative levels in cervical myelopathy.

Exploring tribology and material contact science in spine surgery: implications for implant design.

Tribology, an interdisciplinary field concerned with the science of interactions between surfaces in contact and their relative motion, plays a well-established role in the design of orthopedic implants, such as knee and hip replacements. However, its applications in spine surgery have received comparatively less attention in the literature. Understanding tribology is pivotal in elucidating the intricate interactions between metal, polymer, and ceramic components, as well as their interplay with the native human bone. Numerous studies have demonstrated that optimizing tribological factors is key to enhancing the longevity of joints and implants while simultaneously reducing complications and the need for revision surgeries in both arthroplasty and spinal fusion procedures. With an ever-growing and diverse array of spinal implant devices hitting the market for static and dynamic stabilization of the spine, it is important to consider how each of these devices optimizes these parameters and what factors may be inadequately addressed by currently available technology and methods. In this comprehensive review, the authors' objectives were twofold: 1) delineate the unique challenges encountered in spine surgery that could be addressed through optimization of tribological parameters; and 2) summarize current innovations and products within spine surgery that look to optimize tribological parameters and highlight new avenues for implant design and research.

Real-World Implementation of Artificial Intelligence/Machine Learning for Managing Surgical Spine Patients at 2 Academic Health Care Systems.

Decision-making in spine surgery is complex due to patients' heterogeneity and complexity of spinal pathologies and the various surgical options applied to a given pathology. Artificial intelligence/machine learning algorithms provide an opportunity to improve patient selection, surgical planning, and outcomes. The purpose of this article is to present the experience and applications of in spine surgery at 2 large academic health care systems.

Surgical classification using natural language processing of informed consent forms in spine surgery.

OBJECTIVE: In clinical spine surgery research, manually reviewing surgical forms to categorize patients by their surgical characteristics is a crucial yet time-consuming task. Natural language processing (NLP) is a machine learning tool used to adaptively parse and categorize important features from text. These systems function by training on a large, labeled data set in which feature importance is learned prior to encountering a previously unseen data set. The authors aimed to design an NLP classifier for surgical information that can review consent forms and automatically classify patients by the surgical procedure performed. METHODS: Thirteen thousand two hundred sixty-eight patients who underwent 15,227 surgeries from January 1, 2012, to December 31, 2022, at a single institution were initially considered for inclusion. From these surgeries, 12,239 consent forms were classified based on the Current Procedural Terminology (CPT) code, categorizing them into 7 of the most frequently performed spine surgeries at this institution. This labeled data set was split 80%/20% into train and test subsets, respectively. The NLP classifier was then trained and the results demonstrated its performance on the test data set using CPT codes to determine accuracy. RESULTS: This NLP surgical classifier had an overall weighted accuracy rate of 91% for sorting consents into correct surgical categories. Anterior cervical discectomy and fusion had the highest positive predictive value (PPV; 96.8%), whereas lumbar microdiscectomy had the lowest PPV in the testing data (85.0%). Sensitivity was highest for lumbar laminectomy and fusion (96.7%) and lowest for the least common operation, cervical posterior foraminotomy (58.3%). Negative predictive value and specificity were > 95% for all surgical categories. CONCLUSIONS: Utilizing NLP for text classification drastically improves the efficiency of classifying surgical procedures for research purposes. The ability to quickly classify surgical data can be significantly beneficial to institutions without a large database or substantial data review capabilities, as well as for trainees to track surgical experience, or practicing surgeons to evaluate and analyze their surgical volume. Additionally, the capability to quickly and accurately recognize the type of surgery will facilitate the extraction of new insights from the correlations between surgical interventions and patient outcomes. As the database of surgical information grows from this institution and others in spine surgery, the accuracy, usability, and applications of this model will continue to increase.

Leveraging published randomized controlled trials to inform clinical trial design: a simulation-based study of laminectomy versus laminectomy and fusion.

OBJECTIVE: The US-based Spinal Laminectomy versus Instrumented Pedicle Screw (SLIP) trial reported improvement in disability following laminectomy with fusion versus laminectomy alone for patients with lumbar spondylolisthesis. Despite using similar methods, a concurrent Swedish trial investigating the same question did not reach the same conclusion. The authors performed a simulation-based analysis to elucidate potential causes of these divergent results. METHODS: The mean and standard deviation of the preoperative and 2-year postoperative Oswestry Disability Index (ODI) scores for each study group (laminectomy with fusion and laminectomy alone) were collected from the spondylolisthesis stratum of the Swedish trial and used to create a MATLAB simulator using linear transformations to predict postoperative ODI distributions. Applying this simulator to both varied and published preoperative ODI distributions from the SLIP trial, the authors simulated the results of the US-based trial using treatment effects from the Swedish study and compared simulated US results to those published in the SLIP trial. RESULTS: Simulated US results showed that as preoperative disability increased, the difference in postoperative ODI scores grew between treatment groups and increasingly favored laminectomy alone (p < 0.0001). In 100 simulations of a similarly sized US trial, the average mean change in ODI scores postoperatively was significantly higher than was published for laminectomy alone in the SLIP trial (-21.3 vs -17.9), whereas it was significantly lower than published for fusion (-16.9 vs -26.3). CONCLUSIONS: The expected benefit of surgical treatments for spondylolisthesis varied according to preoperative disability. Adapting Swedish-estimated treatment effects to the US context mildly overapproximated the improvement in postoperative disability scores for laminectomy, but more severely underapproximated the improvement reported for laminectomy and fusion in the SLIP trial. The observed heterogeneity between these studies is influenced more by patient response to fusion than response to laminectomy. This analysis paves the way for future studies on the impact of preoperative treatment group heterogeneity, differences in surgical methods, and empirical design on reported clinical benefits. Although bayesian reanalysis of published randomized controlled trial data is susceptible to biases that typically limit post hoc analyses, the authors' method offers a simple and cost-effective approach to improve the understanding of published clinical trial results and their implications for future studies.

Perioperative outcomes of cervical disc arthroplasty: no difference between orthopaedic and neurologic surgeons.

Background: Given differences in residency training background, there has been increasing interest in characterizing differential outcomes between orthopaedic surgeons (OS) and neurosurgeons (NS) with regards to outcomes after cervical disc arthroplasty (CDA). This study aimed to assess if there were differences in perioperative outcomes of CDA between OS and NS. Methods: Patients who underwent a single-level CDA between 2012 and 2019 were identified from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database using current procedural terminology codes. The patients were subsequently stratified into those who underwent CDA with OS versus NS, and propensity score-matched to adjust for differences in patient characteristics. Differences were assessed in medical and surgical complications, as well as operative time and healthcare utilization parameters [reoperations, readmissions, and lengths-of-stay (LOS)]. Results: A total of 2,148 patients were identified (NS: n=1,395; OS: n=753). After 1:1 propensity score matching (n=741 each), there were no differences in characteristics between patients who underwent CDA by OS versus NS (P>0.05). There were no significant differences in any of the medical or surgical complications between the two groups (P>0.05 for each). There was a significant difference in the operative time between NS and OS (103.7±36.18 vs. 98.75±36.69 minutes; P=0.009). There were no significant differences in readmissions, reoperations, or LOS between the two groups (P>0.05 for each). Conclusions: There were no differences in medical or surgical complications, as well as in reoperations, readmissions, and LOS in patients who underwent a single-level CDA between OS and NS. There was a statistically significant shorter operative time of four minutes for OS as compared to NS, which is unlikely to have clinical relevance.

The Effect of Cervical and Lumbar Decompression Surgery for Spinal Stenosis on Erectile Dysfunction.

STUDY DESIGN: Observational study. OBJECTIVES: To evaluate the prevalence of erectile dysfunction and evaluate the effects of decompressive surgery on erectile dysfunction in cervical spinal stenosis and lumbar canal stenosis patients. METHODS: This observational, prospective analysis enrolled patients aged 18-80 with cervical spinal stenosis and/or lumbar canal stenosis that underwent respective decompressive surgery. The IIEF-5 questionnaire was administered preoperatively, and at 6- and 12-months postoperatively to assess erectile dysfunction severity. The EPIC database was queried to determine any postoperative complications and document prominent erectile dysfunction risk factors. RESULTS: Of 79 patients included in the analysis, 42 (53.2%) completed the IIEF-5 at 6 months, and 62 (78.5%) completed it at 12 months. Eighteen had cervical stenosis only, 54 had lumbar stenosis only, and 7 had both. 72% (18/25) of cervical stenosis patients and 83.6% (51/61) of lumbar stenosis patients had erectile dysfunction preoperatively according to IIEF-5 responses. The average preoperative IIEF-5 score indicated significant presence of erectile dysfunction for both the cervical and lumbar stenosis groups. No significant differences were identified in IIEF-5 score deltas from pre- to both postoperative periods. The presence of erectile dysfunction in both the cervical and lumbar stenosis groups was not significantly associated with the presence of any documented risk factors. CONCLUSIONS: Our results suggest no significant improvement in overall erectile function postoperatively for patients with preoperative erectile dysfunction. This is important to address during patient counseling for decompression surgery candidates with cervical spinal stenosis and/or lumbar canal stenosis to manage expectations.

Factors Affecting the Decision to Initiate Anticoagulation After Spine Surgery: Findings From the AOSpine Anticoagulation Global Initiative.

STUDY DESIGN: Cross-sectional, international survey. OBJECTIVES: To identify factors influencing pharmacologic anticoagulation initiation after spine surgery based on the AOSpine Anticoagulation Global Survey. METHODS: This survey was distributed to the international membership of AOSpine (n = 3805). A Likert-type scale described grade practice-specific factors on a scale from low (1) to high (5) importance, and patient-specific factors a scale from low (0) to high (3) importance. Analysis was performed to determine which factors were significant in the decision making surrounding the initiation of pharmacologic anticoagulation. RESULTS: A total of 316 spine surgeons from 64 countries completed the survey. In terms of practice-specific factors considered to initiate treatment, expert opinion was graded the highest (mean grade ± SD = 3.2 ± 1.3), followed by fellowship training (3.2 ± 1.3). Conversely, previous studies (2.7 ± 1.2) and unspecified guidelines were considered least important (2.6 ± 1.6). Patient body mass index (2.0 ± 1.0) and postoperative mobilization (2.3 ± 1.0) were deemed most important and graded highly overall. Those who rated estimated blood loss with greater importance in anticoagulation initiation decision making were more likely to administer thromboprophylaxis at later times (hazard ratio [HR] = 0.68-0.71), while those who rated drain output with greater importance were likely to administer thromboprophylaxis at earlier times (HR = 1.32-1.43). CONCLUSION: Among our global cohort of spine surgeons, certain patient factors (ie, patient mobilization and body mass index) and practice-specific factors (ie, expert opinion and fellowship training) were considered to be most important when considering anticoagulation start times.

Analysis of Patient-reported Outcomes Measures Used in Lumbar Fusion Surgery Research for Degenerative Spondylolisthesis.

STUDY DESIGN: Meta-analyses. OBJECTIVE: This study aims to document the most common Patient-reported Outcome Measures (PROMs) used to assess lumbar fusion surgery outcomes and provide an estimate of the average improvement following surgical treatment. SUMMARY OF BACKGROUND DATA: As health care institutions place more emphasis on quality of care, accurately quantifying patient perceptions has become a valued tool in measuring outcomes. To this end, greater importance has been placed on the use of PROMs. This is a systemic review and meta-analysis of randomly controlled trials published between 2014 and 2019 assessing surgical treatment of degenerative spondylolisthesis. METHODS: A fixed effect size model was used to calculate mean difference and a 95% confidence interval (95% CI). Linear regression was used to calculate average expected improvement, adjusted for preoperative scores. RESULTS: A total of 4 articles (7 study groups) were found for a total of 444 patients. The 3 most common PROMs were Oswestry Disability Index (ODI) (n=7, 100%), Short-Form-12 or Short-Form-36 (SF-12/36) (n=4, 57.1%), and visual analog scale-back pain (n=3, 42.8%). Pooled average improvement was 24.12 (95% CI: 22.49-25.76) for ODI, 21.90 (95% CI: 19.71-24.08) for SF-12/36 mental component score, 22.74 (95% CI: 20.77-24.71) for SF-12/36 physical component score, and 30.87 (95% CI: 43.79-47.97) for visual analog scale-back pain. After adjusting for preoperative scores, patients with the mean preoperative ODI (40.47) would be expected to improve by 22.83 points postoperatively. CONCLUSIONS: This study provides a range of expected improvement for common PROMs used to evaluate degenerative spondylolisthesis with the goal of equipping clinicians with a benchmark value to use when counseling patients regarding surgery. In doing so, it hopes to provide a comparison point by which to judge individual patient improvement. LEVEL OF EVIDENCE: Level II.

The change in postoperative opioid prescribing after lumbar decompression surgery following state-level opioid prescribing reform.

OBJECTIVE: On August 31, 2017, the state of Ohio implemented legislation limiting the dosage and duration of opioid prescriptions. Despite the widespread adoption of such restrictions, few studies have investigated the effects of these reforms on opioid prescribing and patient outcomes. In the present study, the authors aimed to evaluate the effect of recent state-level reform on opioid prescribing, patient-reported outcomes (PROs), and postoperative emergency department (ED) visits and hospital readmissions after elective lumbar decompression surgery. METHODS: This study was a retrospective cohort study of patients who underwent elective lumbar laminectomy for degenerative disease at one of 5 hospitals within a single health system in the years prior to and after the implementation of the statewide reform (September 1, 2016-August 31, 2018). Patients were classified according to the timing of their surgery relative to implementation of the prescribing reform: before reform (September 1, 2016-August 31, 2017) or after reform (September 1, 2017- August 31, 2018). The outcomes of interest included total outpatient opioids prescribed in the 90 days following discharge from surgery as measured in morphine-equivalent doses (MEDs), total number of opioid refill prescriptions written, patient-reported pain at the first postoperative outpatient visit as measured by the Numeric Pain Rating Scale, improvement in patient-reported health-related quality of life as measured by the Patient-Reported Outcomes Measurement Information System-Global Health (PROMIS-GH) questionnaire, and ED visits or hospital readmissions within 90 days of surgery. RESULTS: A total of 1031 patients met the inclusion criteria for the study, with 469 and 562 in the before- and after-reform groups, respectively. After-reform patients received 26% (95% CI 19%-32%) fewer MEDs in the 90 days following discharge compared with the before-reform patients. No significant differences were observed in the overall number of opioid prescriptions written, PROs, or postoperative ED or hospital readmissions within 90 days in the year after the implementation of the prescribing reform. CONCLUSIONS: Patients undergoing surgery in the year after the implementation of a state-level opioid prescribing reform received significantly fewer MEDs while reporting no change in the total number of opioid prescriptions, PROs, or postoperative ED visits or hospital readmissions. These results demonstrate that state-level reforms placing reasonable limits on opioid prescriptions written for acute pain may decrease patient opioid exposure without negatively impacting patient outcomes after lumbar decompression surgery.

Predictors of Operative Duration and Complications in Single-Level Posterior Interbody Fusions for Degenerative Spondylolisthesis.

BACKGROUND: The goal of this study was to identify predictors of prolonged operative time (OT) in patients receiving posterior/transforaminal lumbar interbody fusion (P/TLIF) and examine the relationship between prolonged OT and perioperative outcomes in this population. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients undergoing single-level P/TLIF (Common Procedural Terminology code) between 2012 and 2018. Multivariable linear regression models were constructed to identify factors independently associated with changes in OT and examine the relationship between prolonged OT and perioperative outcomes (overall complications, surgical complications, medical complications, 30-day readmission, 30-day reoperation, and length of stay). All models were adjusted for sociodemographic variables, comorbidities, and procedure-specific variables. RESULTS: Our cohort included 6260 patients. After adjusting for baseline covariates, age between 19 and 39 years increased OT by 15.14 minutes, male sex increased OT by 12.91 minutes, African American race increased OT by 17.82 minutes, other race increased OT by 18.13 minutes, obesity class III increased OT by 27.80 minutes, and the use of navigation increased OT by 10.83 minutes. Our multivariate logistic regression also found that after 2 hours, each additional hour of OT was associated with an increased risk of any complication (3-3.99 hours, odds ratio [OR], 1.68; 4-4.99 hours, OR, 2.33; and >5 hours, OR, 4.65). Incremental increases in OT were also associated with an increased risk of extended length of stay, readmission, and return to the operating room. CONCLUSIONS: The results of this study highlight several factors associated with prolonged OT and underscore its association with poorer perioperative outcomes. These data can be used to risk stratify patients before single-level P/TLIF.

Late-week surgery and discharge to specialty care associated with higher costs and longer lengths of stay after elective lumbar laminectomy.

OBJECTIVE: In a healthcare landscape in which costs increasingly matter, the authors sought to distinguish among the clinical and nonclinical drivers of patient length of stay (LOS) in the hospital following elective lumbar laminectomy-a common spinal surgery that may be reimbursed using bundled payments-and to understand their relationships with patient outcomes and costs. METHODS: Patients ≥ 18 years of age undergoing laminectomy surgery for degenerative lumbar spinal stenosis within the Cleveland Clinic health system between March 1, 2016, and February 1, 2019, were included in this analysis. Generalized linear modeling was used to assess the relationships between the day of surgery, patient discharge disposition, and hospital LOS, while adjusting for underlying patient health risks and other nonclinical factors, including the hospital surgery site and health insurance. RESULTS: A total of 1359 eligible patients were included in the authors' analysis. The mean LOS ranged between 2.01 and 2.47 days for Monday and Friday cases, respectively. The LOS was also notably longer for patients who were ultimately discharged to a skilled nursing facility (SNF) or rehabilitation center. A prolonged LOS occurring later in the week was not associated with greater underlying health risks, yet it nevertheless resulted in greater costs of care: the average total surgical costs for lumbar laminectomy were 20% greater for Friday cases than for Monday cases, and 24% greater for late-week cases than for early-week cases ultimately transferred to SNFs or rehabilitation centers. A Poisson generalized linear model fit the data best and showed that the comorbidity burden, surgery at a tertiary care center versus a community hospital, and the incidence of any postoperative complication were associated with significantly longer hospital stays. Discharge to home healthcare, SNFs, or rehabilitation centers, and late-week surgery were significant nonclinical predictors of LOS prolongation, even after adjusting for underlying patient health risks and insurance, with LOSs that were, for instance, 1.55 and 1.61 times longer for patients undergoing their procedure on Thursday and Friday compared to Monday, respectively. CONCLUSIONS: Late-week surgeries are associated with a prolonged LOS, particularly when discharge is to an SNF or rehabilitation center. These findings point to opportunities to lower costs and improve outcomes associated with elective surgical care. Interventions to optimize surgical scheduling and perioperative care coordination could help reduce prolonged LOSs, lower costs, and, ultimately, give service line management personnel greater flexibility over how to use existing resources as they remain ahead of healthcare reforms.

Key drivers of patient satisfaction with spine surgeons in the outpatient setting.

OBJECTIVE: The Consumer Assessment of Healthcare Providers and Systems Clinician & Group Survey (CG-CAHPS) was developed as a result of the value-based purchasing initiative by the Center for Medicare & Medicaid Services. It allows patients to rate their experience with their provider in the outpatient setting. These ratings are then reported in aggregate and made publicly available, allowing patients to make informed choices during physician selection. In this study, the authors sought to elucidate the primary drivers of patient satisfaction in the office-based spine surgery setting as represented by the CG-CAHPS. METHODS: All patients who underwent lumbar spine surgery between 2009 and 2017 and completed a patient experience survey were studied. The satisfied group comprised patients who selected a top-box score (9 or 10) for overall provider rating (OPR) on the CG-CAHPS, while the unsatisfied group comprised the remaining patients. Demographic and surgical characteristics were compared using the chi-square test for categorical variables and the Student t-test for continuous variables. A multivariable logistic regression model was developed to analyze the association of patient and surgeon characteristics with OPR. Survey items were then added to the baseline model individually, adjusting for covariates. RESULTS: The study population included 647 patients who had undergone lumbar spine surgery. Of these patients, 564 (87%) selected an OPR of 9 or 10 on the CG-CAHPS and were included in the satisfied group. Patient characteristics were similar between the two groups. The two groups did not differ significantly regarding patient-reported health status measures. After adjusting for potential confounders, the following survey items were associated with the greatest odds of selecting a top-box OPR: did this provider show respect for what you had to say? (OR 21.26, 95% CI 9.98-48.10); and did this provider seem to know the important information about your medical history? (OR 20.93, 95% CI 11.96-45.50). CONCLUSIONS: The present study sought to identify the key drivers of patient satisfaction in the postoperative office-based spine surgery setting and found several important associations. After adjusting for potential confounders, several items relating to physician communication were found to be the strongest predictors of patient satisfaction. This highlights the importance of effective communication in the patient-provider interaction and elucidates avenues for quality improvement efforts in the spine care setting.

The association of preoperative TNF-alpha inhibitor use and reoperation rates in spinal fusion surgery.

BACKGROUND CONTEXT: Preoperative TNF-AI use has been associated with increased rate of postoperative infections and complications in a variety of orthopedic procedures. However, the association between TNF-AI use and complications following spine surgery has not yet been studied. PURPOSE: The purpose of the present study was to assess the risk of reoperation in patients prescribed TNF-AI undergoing spinal fusion surgery. STUDY DESIGN: This is a retrospective review. PATIENT SAMPLE: A total of 427 patients who underwent spinal fusion surgery at a large healthcare system from 1/1/2009 to 12/31/2018. OUTCOME MEASURE: Reoperation within 1 year. METHODS: We retrospectively reviewed the records of patients who underwent spinal fusion surgery at a large healthcare system from 1/1/2009 to 12/31/2018. There were three distinct cohorts of spine surgery patients under study: patients with TNF-AI use in 90 days before surgery, patients with non-TNF-AI DMARD medications use in the 90 days before surgery, and patients taking neither TNF-AI nor other DMARD medications in 90 days before surgery. The primary outcome of interest was reoperation for any reason within 1 year following surgery. RESULTS: Our study included 90 TNF-AI, 90 DMARD, and 123 control patients. Reoperation up to 1-year postsurgery occurred in 19% (n=17) of the TNF-AI group, 11% (n=10) of the DMARD group, and 6% (n=7) of the control group. The reasons for reoperation for TNF-AI group were 47% (n=8) infection and 53% (n=9) other causes which included failure to fuse and adjacent segment disease. Reasons for reoperation at 1 year were 40% (n=4) infection and 60% (n=6) other causes for DMARD patients and 14% (n=1) infection with 86% (n=6) other causes for control patients. The cox-proportional hazard model of reoperation within 1 year indicated that the odds of reoperation were 3.1 (95% CI:1.4-7.0) and 2.2 (95% CI 0.96-5.3) times higher in the TNF-AI and DMARD groups, respectively, compared to the control group. CONCLUSIONS: Patients taking TNF-AIs before surgery were found to have a significantly higher rate of reoperation in the 1 year following surgery compared to controls. The higher rate of reoperation associated with TNF-AI use before spinal fusion surgery represents the potential for higher morbidity and costs for patient which is important to consider for both surgeon and patient in preoperative decision making.

Patient-specific prediction model for clinical and quality-of-life outcomes after lumbar spine surgery.

OBJECTIVE: Patient demographics, comorbidities, and baseline quality of life (QOL) are major contributors to postoperative outcomes. The frequency and cost of lumbar spine surgery has been increasing, with controversy revolving around optimal management strategies and outcome predictors. The goal of this study was to generate predictive nomograms and a clinical calculator for postoperative clinical and QOL outcomes following lumbar spine surgery for degenerative disease. METHODS: Patients undergoing lumbar spine surgery for degenerative disease at a single tertiary care institution between June 2009 and December 2012 were retrospectively reviewed. Nomograms and an online calculator were modeled based on patient demographics, comorbidities, presenting symptoms and duration of symptoms, indication for surgery, type and levels of surgery, and baseline preoperative QOL scores. Outcomes included postoperative emergency department (ED) visit or readmission within 30 days, reoperation within 90 days, and 1-year changes in the EuroQOL-5D (EQ-5D) score. Bootstrapping was used for internal validation. RESULTS: A total of 2996 lumbar surgeries were identified. Thirty-day ED visits were seen in 7%, 30-day readmission in 12%, 90-day reoperation in 3%, and improvement in EQ-5D at 1 year that exceeded the minimum clinically important difference in 56%. Concordance indices for the models predicting ED visits, readmission, reoperation, and dichotomous 1-year improvement in EQ-5D were 0.63, 0.66, 0.73, and 0.84, respectively. Important predictors of clinical outcomes included age, body mass index, Charlson Comorbidity Index, indication for surgery, preoperative duration of symptoms, and the type (and number of levels) of surgery. A web-based calculator was created, which can be accessed here: https://riskcalc.org/PatientsEligibleForLumbarSpineSurgery/. CONCLUSIONS: The prediction tools derived from this study constitute important adjuncts to clinical decision-making that can offer patients undergoing lumbar spine surgery realistic and personalized expectations of postoperative outcome. They may also aid physicians in surgical planning, referrals, and counseling to ultimately lead to improved patient experience and outcomes.

The Impact of Preoperative Depression on Patient Satisfaction With Spine Surgeons in the Outpatient Setting.

STUDY DESIGN: Retrospective review. OBJECTIVE: The aim of this study was to examine the association between preoperative depression and patient satisfaction in the outpatient spine clinic after lumbar surgery. SUMMARY OF BACKGROUND DATA: The Clinician and Group Assessment of Healthcare Providers and Systems (CG-CAHPS) survey is used to measure patient experience in the outpatient setting. CG-CAHPS scores may be used by health systems in physician incentive programs and quality improvement initiatives or by prospective patients when selecting spine surgeons. Although preoperative depression has been shown to predict poor patient-reported outcomes and less satisfaction with the inpatient experience following lumbar surgery, its impact on patient experience with spine surgeons in the outpatient setting remains unclear. METHODS: Patients who underwent lumbar surgery and completed the CG-CAHPS survey at postoperative follow-up with their spine surgeon between 2009 and 2017 were included. Data were collected on patient demographics, Patient Health Questionnaire 9 (PHQ-9) scores, and Patient-Reported Outcome Measurement Information System Global Health Physical Health (PROMIS-GPH) subscores. Patients with preoperative PHQ-9 scores ≥10 (moderate-to-severe depression) were included in the depressed cohort. The association between preoperative depression and top-box satisfaction ratings on several dimensions of the CG-CAHPS survey was examined. RESULTS: Of the 419 patients included in this study, 72 met criteria for preoperative depression. Depressed patients were less likely to provide top-box satisfaction ratings on CG-CAHPS metrics pertaining to physician communication and overall provider rating (OPR). Even after controlling for patient-level covariates, our multivariate analysis revealed that depressed patients had lower odds of reporting top-box OPR (odds ratio [OR]: 0.19, 95% confidence interval [CI]: 0.06-0.63, P = 0.007), feeling that their spine surgeon provided understandable explanations (OR: 0.32, 95% CI: 0.11-0.91, P = 0.032), and feeling that their spine surgeon provided understandable responses to their questions or concerns (OR: 0.19, 95% CI: 0.06-0.63, P = 0.007). CONCLUSION: Preoperative depression is independently associated with lower OPR and satisfaction with spine surgeon communication in the outpatient setting after lumbar surgery.Level of Evidence: 3.

Is it safe to stop at C7 during multilevel posterior cervical decompression and fusion? - multicenter analysis.

BACKGROUND CONTEXT: Despite a number of studies addressing the anatomical and biomechanical challenges of long segment, posterior cervical fusion surgery, recommendations for appropriate caudal "end level" vary widely. PURPOSE: Compare revision rates, patient reported outcomes and radiographic outcomes in patients in whom 3+ level posterior fusions ended in the cervical spine versus those in whom the fusion was extended into the thoracic spine. STUDY DESIGN: Multicenter retrospective analysis. OUTCOME MEASURES: Visual analog scale (VAS), Oswestry disability index (ODI), cervical lordosis, C2-C7 sagittal plumbline, T1 slope, and revision rate. METHODS: We assembled a radiographic and clinical database of patients that had undergone three or more level posterior cervical fusions for degenerative disease from January 2013 to May 2015 at one of four busy spine centers. Only those patients with at least 2 years of postoperative (postop) follow-up were included. Patients were divided into two groups: group I (fusion ending at C6 or C7) and group II (fusion extending into the thoracic spine). All radiographic measurements (cervical lordosis, T1 slope, and C2-C7 sagittal plumbline) were performed by an independent experienced clinical researcher. RESULTS: Two hundred and sixty-four patient cases were reviewed and sorted into the two outlined groups, Group I (n=168) and Group II (n=96). Demographically, mean age, percentage of females, non-smokers and anterior support were greater in Group II than in Groups I (p<.05). Mean estimated blood loss (EBL), operative time (OR) and length of hospital stay (LOS) were significantly higher in Group II (p<.05). Rate of revision was not clinically or statistically significantly different (p>.05) between Group I (11.1%) and Group II (9.4%). The majority of the revision surgeries occurred between 2 to 5 years postop. A greater number of subjacent degeneration/spondylolisthesis events were noted in Group I compared with Group II (3.6% vs. 1.2%). There were significant improvements in mean clinical outcomes (ie, VAS and ODI) at two years postop in both groups, but there were no statistically significant differences between the groups (p>.05). Mean cervical lordosis at 2 years postop improved in all groups (12.8° vs. 14.1°); however, there was no significant statistical difference in change for mean cervical lordosis (2 weeks vs. 2 year postop) between the two groups. Similary, there were no significant statistical differences in change for mean C2-C7 sagittal plumbline and T1 slope (2 weeks vs. 2 year postop) between the two groups(p>.05). CONCLUSIONS: Caudal end level did not significantly affect revision rates, patient reported outcomes or radiographic outcomes. Higher EBL, OR, and LOS in group II suggest that, absent focal C7-T1 pathology, extension of posterior cervical fusions into the thoracic spine may not be necessary. Extension of posterior cervical fusions into the thoracic spine may be recommended for higher risk patients with limitations to strong C7 bone anchorage. In others, it is safe to stop at C7.

Associations Between Preoperative Hyponatremia and 30-Day Perioperative Complications in Lumbar Interbody Spinal Fusion.

STUDY DESIGN: Retrospective population database study. OBJECTIVE: To investigate the relationship of preoperative hyponatremia to postoperative morbidity and mortality in lumbar interbody fusion patients. SUMMARY OF BACKGROUND DATA: Optimization of preoperative patient selection and perioperative management can improve patient outcomes in spinal surgery. Hyponatremia, incidentally identified in 1.7% of the US population, has previously been tied to poorer postoperative outcomes in both the general surgery and orthopedic surgery populations. MATERIALS AND METHODS: Using the National Surgical Quality Improvement Program database, the authors identified all lumbar interbody fusion patients treated between 2012 and 2014. Patients were classified as hyponatremic (Na<135 mEq/L) or as having normal sodium levels (135-145 mEq/L) preoperatively. The primary outcome was major morbidity and secondary endpoints were prolonged hospitalization, 30-day readmission, and reoperation. Multivariable linear regression was used to find independent predictors of these outcomes. RESULTS: Of 10,654 patients, 45.6% were male individuals, 5.5% were hyponatremic, and 4.2% experienced a major postoperative complication. On multivariable analysis, preoperative hyponatremia was independently associated with major morbidity (odds ratio, 1.22; 95% confidence interval, 1.03-1.44; P<0.05) and prolonged hospitalization (odds ratio, 1.14; 95% confidence interval, 1.02-1.27). CONCLUSIONS: Here the authors provide the first evidence suggesting preoperative hyponatremia is an independent predictor of major morbidity after lumbar interbody fusion. Hyponatremia may represent a modifiable risk factor for improved patient care and preoperative risk counseling.