Multivariable Prediction Models for Traumatic Spinal Cord Injury: A Systematic Review.

Background: Traumatic spinal cord injuries (TSCI) greatly affect the lives of patients and their families. Prognostication may improve treatment strategies, health care resource allocation, and counseling. Multivariable clinical prediction models (CPMs) for prognosis are tools that can estimate an absolute risk or probability that an outcome will occur. Objectives: We sought to systematically review the existing literature on CPMs for TSCI and critically examine the predictor selection methods used. Methods: We searched MEDLINE, PubMed, Embase, Scopus, and IEEE for English peer-reviewed studies and relevant references that developed multivariable CPMs to prognosticate patient-centered outcomes in adults with TSCI. Using narrative synthesis, we summarized the characteristics of the included studies and their CPMs, focusing on the predictor selection process. Results: We screened 663 titles and abstracts; of these, 21 full-text studies (2009-2020) consisting of 33 distinct CPMs were included. The data analysis domain was most commonly at a high risk of bias when assessed for methodological quality. Model presentation formats were inconsistently included with published CPMs; only two studies followed established guidelines for transparent reporting of multivariable prediction models. Authors frequently cited previous literature for their initial selection of predictors, and stepwise selection was the most frequent predictor selection method during modelling. Conclusion: Prediction modelling studies for TSCI serve clinicians who counsel patients, researchers aiming to risk-stratify participants for clinical trials, and patients coping with their injury. Poor methodological rigor in data analysis, inconsistent transparent reporting, and a lack of model presentation formats are vital areas for improvement in TSCI CPM research.

Rethinking cervical spine clearance in obtunded trauma patients: An updated systematic review and meta-analysis.

BACKGROUND: Cervical spine injuries (CSI) are often challenging to diagnose in obtunded adult patients with blunt trauma and the optimal imaging modality remains uncertain. This study systematically synthesized the last decade of evidence to determine the type of imaging required to clear the c-spine in obtunded patients with blunt trauma. METHODS: A systematic review with meta-analysis was conducted and reported using PRISMA 2020 guidelines. The protocol was registered on June 22, 2022 (PROSPERO CRD42022341386). MEDLINE (Ovid), EMBASE, and Cochrane Library were searched for studies published between January 1, 2012, and October 17, 2023. Studies comparing CT alone to CT combined with MRI for c-spine clearance were included. Two independent reviewers screened articles for eligibility in duplicate. Meta-analysis was conducted using a random-effect model. Risk of bias and quality assessment were performed using the ROBINS-I and QUADAS-2. The certainty of evidence was assessed using the GRADE methodology. RESULTS: 744 obtunded trauma patients from six included studies were included. Among the 584 that had a negative CT scan, the pooled missed rate of clinically significant CSI using CT scans alone was 6 % (95 % CI: 0.02 to 0.17), and the pooled missed rate of CSI requiring treatment was 7 % (95 % CI: 0.02 to 0.18). High heterogeneity was observed among included studies (I² > 84 %). The overall risk of bias was moderate, and the quality of evidence was low due to the retrospective nature of the included studies and high heterogeneity. CONCLUSIONS: Limited evidence published in the last decade found that CT scans alone may not be sufficient for detecting clinically significant CSI and injuries requiring treatment in obtunded adult patients with blunt trauma. IMPLICATIONS OF KEY FINDINGS: Clinicians should be aware of the limitations of CT scans and consider using MRI when appropriate. Future research should focus on prospective studies with standardized outcome measures and uniform reporting.

Enabling knowledge translation: implementation of a web-based tool for independent walking prediction after traumatic spinal cord injury.

Introduction: Several clinical prediction rules (CPRs) have been published, but few are easily accessible or convenient for clinicians to use in practice. We aimed to develop, implement, and describe the process of building a web-based CPR for predicting independent walking 1-year after a traumatic spinal cord injury (TSCI). Methods: Using the published and validated CPR, a front-end web application called "Ambulation" was built using HyperText Markup Language (HTML), Cascading Style Sheets (CSS), and JavaScript. A survey was created using QualtricsXM Software to gather insights on the application's usability and user experience. Website activity was monitored using Google Analytics. Ambulation was developed with a core team of seven clinicians and researchers. To refine the app's content, website design, and utility, 20 professionals from different disciplines, including persons with lived experience, were consulted. Results: After 11 revisions, Ambulation was uploaded onto a unique web domain and launched (www.ambulation.ca) as a pilot with 30 clinicians (surgeons, physiatrists, and physiotherapists). The website consists of five web pages: Home, Calculation, Team, Contact, and Privacy Policy. Responses from the user survey (n = 6) were positive and provided insight into the usability of the tool and its clinical utility (e.g., helpful in discharge planning and rehabilitation), and the overall face validity of the CPR. Since its public release on February 7, 2022, to February 28, 2023, Ambulation had 594 total users, 565 (95.1%) new users, 26 (4.4%) returning users, 363 (61.1%) engaged sessions (i.e., the number of sessions that lasted 10 seconds/longer, had one/more conversion events e.g., performing the calculation, or two/more page or screen views), and the majority of the users originating from the United States (39.9%) and Canada (38.2%). Discussion: Ambulation is a CPR for predicting independent walking 1-year after TSCI and it can assist frontline clinicians with clinical decision-making (e.g., time to surgery or rehabilitation plan), patient education and goal setting soon after injury. This tool is an example of adapting a validated CPR for independent walking into an easily accessible and usable web-based tool for use in clinical practice. This study may help inform how other CPRs can be adopted into clinical practice.

Prevalence of Lumbosacral Transitional Vertebral Anomalies Among Healthy Volunteers and Patients with Hip Pathology: Association with Spinopelvic Characteristics.

A lumbosacral transitional vertebra (LSTV) has been reported to be prevalent among patients with hip dysplasia. The aims of this study were to determine the (1) prevalence of an LSTV in young patients presenting with hip pain and a group of asymptomatic volunteers, (2) effect of an LSTV on spinopelvic characteristics, and (3) presence of low back pain among patients with an LSTV. Methods: This cross-sectional study included 102 patients with hip pathology and 51 asymptomatic volunteers (mean age, 33.9 ± 7.3 years; mean body mass index, 26.0 ± 5.0 kg/m2; 57.5% female). Participants underwent radiographic assessment of the lumbar spine and pelvis in standing and deep-seated positions. LSTV occurrence was classified according to the Castellvi system. Spinopelvic characteristics included lumbar lordosis (including segmental lumbar angles), pelvic tilt, and hip flexion (pelvic-femoral angle). Differences between standing and deep-seated values were calculated. Low back pain was assessed using the Oswestry Disability Index. Results: The prevalence of LSTV type ≥II was 8.5%, with no difference between patients and volunteers (p = 0.386). Individuals with an LSTV had a greater standing L1-L5 angle (mean, 51.6° ± 11.7° versus 38.9° ± 9.3°; p < 0.001). The overall spinal flexion (change in L1-S1 angle between the standing and deep-seated positions) in individuals with an LSTV was similar to that in individuals without an LSTV; restricted L5-S1 mobility was compensated for at L1-L2 (10.2° ± 5.8° in those with versus 8.4° ± 4.1° in those without an LSTV; p = 0.070). No significant difference in the presence of low back pain was found (p = 0.250). Conclusions: An LSTV was found in 8.5% of young adults, with no difference between patients with hip pathology and controls. Individuals with an LSTV have greater standing lumbar lordosis, with altered mechanics at the cephalad adjacent level, which may predispose these individuals to degenerative changes at this level. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

A data-driven approach to categorize patients with traumatic spinal cord injury: cluster analysis of a multicentre database.

Background: Conducting clinical trials for traumatic spinal cord injury (tSCI) presents challenges due to patient heterogeneity. Identifying clinically similar subgroups using patient demographics and baseline injury characteristics could lead to better patient-centered care and integrated care delivery. Purpose: We sought to (1) apply an unsupervised machine learning approach of cluster analysis to identify subgroups of tSCI patients using patient demographics and injury characteristics at baseline, (2) to find clinical similarity within subgroups using etiological variables and outcome variables, and (3) to create multi-dimensional labels for categorizing patients. Study design: Retrospective analysis using prospectively collected data from a large national multicenter SCI registry. Methods: A method of spectral clustering was used to identify patient subgroups based on the following baseline variables collected since admission until rehabilitation: location of the injury, severity of the injury, Functional Independence Measure (FIM) motor, and demographic data (age, and body mass index). The FIM motor score, the FIM motor score change, and the total length of stay were assessed on the subgroups as outcome variables at discharge to establish the clinical similarity of the patients within derived subgroups. Furthermore, we discussed the relevance of the identified subgroups based on the etiological variables (energy and mechanism of injury) and compared them with the literature. Our study also employed a qualitative approach to systematically describe the identified subgroups, crafting multi-dimensional labels to highlight distinguishing factors and patient-focused insights. Results: Data on 334 tSCI patients from the Rick Hansen Spinal Cord Injury Registry was analyzed. Five significantly different subgroups were identified (p-value ≤0.05) based on baseline variables. Outcome variables at discharge superimposed on these subgroups had statistically different values between them (p-value ≤0.05) and supported the notion of clinical similarity of patients within each subgroup. Conclusion: Utilizing cluster analysis, we identified five clinically similar subgroups of tSCI patients at baseline, yielding statistically significant inter-group differences in clinical outcomes. These subgroups offer a novel, data-driven categorization of tSCI patients which aligns with their demographics and injury characteristics. As it also correlates with traditional tSCI classifications, this categorization could lead to improved personalized patient-centered care.

Feasibility of a multidisciplinary Transitional Pain Service in spine surgery patients to minimise opioid use and improve perioperative outcomes: a quality improvement study.

INTRODUCTION: Spine surgery patients have high rates of perioperative opioid consumption, with a chronic opioid use prevalence of 20%. A proposed solution is the implementation of a Transitional Pain Service (TPS), which provides patient-tailored multidisciplinary care. Its feasibility has not been demonstrated in spine surgery. The main objective of this study was to evaluate the feasibility of a TPS programme in patients undergoing spine surgery. METHODS: Patients were recruited between July 2020 and November 2021 at a single, tertiary care academic centre. Success of our study was defined as: (1) enrolment: ability to enrol ≥80% of eligible patients, (2) data collection: ability to collect data for ≥80% of participants, including effectiveness measures (oral morphine equivalent (OME) and Visual Analogue Scale (VAS)-perceived analgesic management and overall health) and programme resource requirements measures (appointment attendance, 60-day return to emergency and length of stay), and (3) efficacy: estimate potential programme effectiveness defined as ≥80% of patients weaned back to their intake OME requirements at programme discharge. RESULTS: Thirty out of 36 (83.3%) eligible patients were enrolled and 26 completed the TPS programme. The main programme outcomes and resource measures were successfully tracked for >80% of patients. All 26 patients had the same or lower OME at programme discharge than at intake (intake 38.75 mg vs discharge 12.50 mg; p<0.001). At TPS discharge, patients reported similar overall health VAS (pre 60.0 vs post 70.0; p=0.14), improved scores for VAS-perceived analgesic management (pre 47.6 vs post 75.6; p<0.001) and improved Brief Pain Inventory pain intensity (pre 39.1 vs post 25.0; p=0.02). CONCLUSION: Our feasibility study successfully met or exceeded our three main objectives. Based on this success and the defined clinical need for a TPS programme, we plan to expand our TPS care model to include other surgical procedures at our centre.

Beneficial Effects of Preoperative Exercise on the Outcomes of Lumbar Fusion Spinal Surgery.

Purpose: To determine whether there was an association between self-reported preoperative exercise and postoperative outcomes after lumbar fusion spinal surgery. Method: We performed a retrospective multivariable analysis of the prospective Canadian Spine Outcomes and Research Network (CSORN) database of 2,203 patients who had elective single-level lumbar fusion spinal surgeries. We compared adverse events and hospital length of stay between patients who reported regular exercise (twice or more per week) prior to surgery ("Regular Exercise") to those exercising infrequently (once or less per week) ("Infrequent Exercise") or those who did no exercise ("No Exercise"). For all final analyses, we compared the Regular Exercise group to the combined Infrequent Exercise or No Exercise group. Results: After making adjustments for known confounding factors, we demonstrated that patients in the Regular Exercise group had fewer adverse events (adjusted odds ratio 0.72; 95% CI: 0.57, 0.91; p = 0.006) and significantly shorter lengths of stay (adjusted mean 2.2 vs. 2.5 d, p = 0.029) than the combined Infrequent Exercise or No Exercise group. Conclusions: Patients who exercised regularly twice or more per week prior to surgery had fewer postoperative adverse events and significantly shorter hospital lengths of stay compared to patients that exercised infrequently or did no exercise. Further study is required to determine effectiveness of a targeted prehabilitation programme.

Objectif : déterminer s'il y avait une association entre les exercices préopératoires autodéclarés et les résultats postopératoires après une chirurgie de fusion lombaire. Méthodologie : analyse multivariable rétrospective de la base de données prospective Canadian Spine Outcomes and Research Network (CSORN) composée de 2 203 patients qui avaient subi une chirurgie de fusion lombaire univertébrale non urgente. Les chercheurs ont comparé les événements indésirables et la durée du séjour hospitalier entre les patients qui déclaraient faire de l'exercice régulier (au moins deux fois par semaine) avant l'opération (« exercice régulier ¼) à ceux qui n'en faisaient pas souvent (une fois ou moins par semaine; « exercice peu fréquent ¼) et qui n'en faisaient pas du tout (« absence d'exercice ¼). Pour toutes les analyses définitives, ils ont comparé le groupe qui faisait de l'exercice régulier aux groupes combinés d'exercice peu fréquent et d'absence d'exercice. Résultats : après correction pour tenir compte des facteurs confusionnels connus, les chercheurs ont démontré que les patients du groupe faisant de l'exercice régulier présentaient moins d'événements indésirables (rapport de cotes rajusté 0,72; IC à 95 % : 0,57, 0,91; p = 0,006) et leur séjour à l'hôpital était significativement plus court (moyenne corrigée 2,2 jours par rapport à 2,5 jours, p = 0,029) que dans le groupe combiné d'exercice peu fréquent et d'absence d'exercice. Conclusions : les patients qui faisaient de l'exercice régulièrement au moins deux fois par semaine avant l'opération présentaient moins d'événements indésirables après l'opération et étaient hospitalisés beaucoup moins longtemps que ceux qui ne faisaient pas beaucoup d'exercice ou n'en faisaient pas du tout. Il faudra réaliser d'autres études pour déterminer l'efficacité d'un programme de préréadaptation ciblé.

Does Ending a Posterior Construct Proximally at C2 Versus C3 Impact Patient Reported Outcomes in Degenerative Cervical Myelopathy Patients up to 24 months After the Surgery?

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The primary objective was to evaluate the impact of the upper instrumented level (UIV) being at C2 vs C3 in posterior cervical construct on patient reported outcomes (PROs) up to 24 months after surgery for cervical degenerative myelopathy (DCM). Secondary objectives were to compare operative time, intra-operative blood loss (IOBL), length of stay (LOS), adverse events (AEs) and re-operation. METHODOLOGY: Patients who underwent a posterior cervical instrumented fusion (3 and + levels) with a C2 or C3 UIV, with 24 months follow-up were analyzed. PROs (NDI, EQ5D, SF-12 PCS/MCS, NRS arm/neck pain) were compared using ANCOVA. Operative duration, IOBL, AEs, and re-operation were compared. Subgroup analysis was performed on patient presenting with pre-operative malalignment (cervical sagittal vertical axis ≥40 mm and/or T1slope- cervical lordosis >15°). RESULTS: 173 patients were included, of which 41 (24%) had a C2 UIV and 132 (76%) a C3 UIV. There was no statistically significant difference between the groups for the changes in PROs up to 24 months. Subgroup analysis of patients with pre-operative malalignment showed a trend towards greater improvement in the NDI at 12 months with a C2 UIV (P = .054). Operative time, IOBL and peri-operative AEs were more in C2 group (P < .05). There was no significant difference in LOS and re-operation (P > .05). CONCLUSION: In this observational study, up to 24 months after surgery for posterior cervical fusion in DCM greater than 3 levels, PROs appear to evolve similarly.

Minimally Invasive Tubular Lumbar Discectomy Versus Conventional Open Lumbar Discectomy: An Observational Study From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: We evaluated the effectiveness of minimally invasive (MIS) tubular discectomy in comparison to conventional open surgery among patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN). METHODS: We performed an observational analysis of data that was prospectively collected. We implemented Minimum Clinically Important Differences (MCIDs), and we adjusted for potential confounders with multiple logistic regression. Adverse events were collected according to the Spinal Adverse Events Severity (SAVES) protocol. RESULTS: Three hundred thirty-nine (62%) patients underwent MIS tubular discectomy and 211 (38%) underwent conventional open discectomy. There were no significant differences between groups for improvement of leg pain and disability, but the MIS technique was associated with reduced odds of achieving the MCID for back pain (OR 0.66, 95% CI 0.44 to 0.99, P < 0.05). We identified statistically significant differences in favor of MIS for each of operating time (MIS mean (SD) 72.2 minutes (30.0) vs open 93.5 (40.9)), estimated blood loss (MIS 37.9 mL (36.7) vs open 76.8 (71.4)), length of stay in hospital (MIS 73% same-day discharge vs open 40%), rates of incidental durotomy (MIS 4% vs open 8%), and wound-related complications (MIS 3% vs open 9%); but not for overall rates of reoperation. CONCLUSIONS: Open and MIS techniques yielded similar improvements of leg pain and disability at up to 12 months of follow-up, but MIS patients were less likely to experience improvement of associated back pain. Small differences favored MIS for operating time, blood loss, and adverse events but may have limited clinical importance.

The effect of a quality improvement project on post-operative opioid use following outpatient spinal surgery.

Background: Prescribing opioids upon discharge after surgery is common practice; however, there are many inherent risks including dependency, diversion, and medical complications. Our prospective pre- and post-intervention study investigates the effect of a standardized analgesic prescription on the quantity of opioids prescribed and patients' level of pain and satisfaction with pain control in the early post-operative period. Methods: With the implementation of an electronic medical record, a standardized prescription was built employing multimodal analgesia and a stepwise approach to analgesics based on level of pain. Patients received an education handout pre-operatively explaining the prescription. Consecutive patients over a three-month period undergoing elective spine surgery as day or overnight stay cases who received usual care were compared to a similar cohort who received the standardized prescription and education. Patient satisfaction with post-operative pain control, post-operative pain scores, number of refills required, and opioids prescribed in oral morphine equivalents (OMEs) were compared before and after implementation of the standardized analgesic prescription. Results: Twenty-six patients received usual care (Control group) and 26 patients received the standardized prescription and education handout (Intervention group). There were significantly fewer OMEs prescribed in the Intervention group compared to the Control group. There was no difference between groups in: patient post-operative pain intensity score, post-operative satisfaction score, or number of refills required. Conclusions: This study demonstrates that a standardized prescription consisting of an appropriate amount of opioid and non-opioid analgesics is effective in reducing the OMEs prescribed post-operatively in elective spine surgery procedures, without compromising patient pain control or satisfaction or increasing the number of refills required.

A scoping review of complication prediction models in spinal surgery: An analysis of model development, validation and impact.

Background: Predictive analytics are being used increasingly in the field of spinal surgery with the development of models to predict post-surgical complications. Predictive models should be valid, generalizable, and clinically useful. The purpose of this review was to identify existing post-surgical complication prediction models for spinal surgery and to determine if these models are being adequately investigated with internal/external validation, model updating and model impact studies. Methods: This was a scoping review of studies pertaining to models for the prediction of post-surgical complication after spinal surgery published over 10 years (2010-2020). Qualitative data was extracted from the studies to include study classification, adherence to Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines and risk of bias (ROB) assessment using the Prediction model study Risk Of Bias Assessment Tool (PROBAST). Model evaluation was determined using area under the curve (AUC) when available. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was used as a basis for the search methodology in four different databases. Results: Thirty studies were included in the scoping review and 80% (24/30) included model development with or without internal validation. Twenty percent (6/30) were exclusively external validation studies and only one study included an impact analysis in addition to model development and internal validation. Two studies referenced the TRIPOD guidelines and there was a high ROB in 100% of the studies using the PROBAST tool. Conclusions: The majority of post-surgical complication prediction models in spinal surgery have not undergone standardized model development and internal validation or adequate external validation and impact evaluation. As such there is uncertainty as to their validity, generalizability, and clinical utility. Future efforts should be made to use existing tools to ensure standardization in development and rigorous evaluation of prediction models in spinal surgery.

Outcome of spine surgery in patients with depressed mental states: a Canadian spine outcome research network study.

BACKGROUND CONTEXT: Depression is higher among spine patients than among the general population. Some small studies, but not others, have suggested that depression may be a predictor of worse outcome after surgery. PURPOSE: Determination whether there is an association between depression and worse response to surgery among spine patients. STUDY DESIGN/SETTING: The national, prospective, Canadian Spine Outcome Research Network (CSORN) surgical outcome registry. PATIENT SAMPLE: All patients in the CSORN registry who received surgery for thoracic or lumbar degenerative deformity, stenosis, spondylolisthesis, disc disease, or disc herniation with a minimum of 12 months follow-up postoperation (n = 2310). OUTCOME MEASURES: Oswestry Disability Index (ODI), SF12 Physical Component Score (PCS), European Quality of Life (EuroQoL), and pain scales. METHODS: Change in preoperative to 12-month postoperative ODI, and secondary measures, were compared to assess if there was an association between preoperative depression, as measured by PHQ9, and smaller response to surgery. Multivariate regression analysis was used to search for preoperative factors which might interact with PHQ9 to predict ODI outcome. RESULTS: Patients with PHQ9<5, associated with minimal to no depression, had the smallest ODI improvement (-16.8 [95%CI -18.1 to -15.3]) and patients with severe preoperative depression (PHQ9 ≥ 10) had the largest ODI improvement (-22.8 [95%CI -24.1 to -21.5]; p<.00001). Similar findings were found in the EQ5D and PCS. Pain improvement was not different between depression levels. Multivariate modeling found worse baseline PHQ9 and ODI, greater age, nicotine use, more operative levels, and worse American Society of Anesthesiology score was predictive of worse ODI outcomes. CONCLUSIONS: Depressed patients have similar or better relative improvements in disability, quality of life, and pain, when compared to nondepressed patients, although their preoperative and postoperative levels of disability are higher. Surgeons should not be concerned that depression will reduce the patient-reported beneficial response to surgical intervention.

Surgical outcomes of patients who fail to reach minimal clinically important differences: comparison of minimally invasive versus open transforaminal lumbar interbody fusion.

OBJECTIVE: Treatment of degenerative lumbar diseases has been shown to be clinically effective with open transforaminal lumbar interbody fusion (O-TLIF) or minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Despite this, a substantial proportion of patients do not meet minimal clinically important differences (MCIDs) in patient-reported outcomes (PROs). The objectives of this study were to compare the proportions of patients who did not meet MCIDs after O-TLIF and MIS-TLIF and to determine potential clinical factors associated with failure to achieve MCID. METHODS: The authors performed a retrospective analysis of consecutive patients who underwent O-TLIF or MIS-TLIF for lumbar degenerative disorders and had been prospectively enrolled in the Canadian Spine Outcomes and Research Network. The authors analyzed the Oswestry Disability Index (ODI) scores, physical and mental component summary scores of SF-12, numeric rating scale (NRS) scores for leg and back pain, and EQ-5D scores of the patients in each group who did not meet the MCID of ODI at 2 years postoperatively. RESULTS: In this study, 38.8% (137 of 353) of patients in the O-TLIF cohort and 41.8% (51 of 122) of patients in the MIS-TLIF cohort did not meet the MCID of ODI at 2 years postoperatively (p = 0.59). Demographic variables and baseline PROs were similar between groups. There were improvements across the PROs of both groups through 2 years, and there were no differences in any PROs between the O-TLIF and MIS-TLIF cohorts. Multivariable logistic regression analysis demonstrated that higher baseline leg pain score (p = 0.017) and a diagnosis of spondylolisthesis (p = 0.0053) or degenerative disc disease (p = 0.022) were associated with achieving the MCID at 2 years after O-TLIF, whereas higher baseline leg pain score was associated with reaching the MCID after MIS-TLIF (p = 0.038). CONCLUSIONS: Similar proportions of patients failed to reach the MCID of ODI at 2 years after O-TLIF or MIS-TLIF. Higher baseline leg pain score was predictive of achieving the MCID in both cohorts, whereas a diagnosis of spondylolisthesis or degenerative disc disease was predictive of reaching the MCID after O-TLIF. These data provide novel insights for patient counseling and suggest that either MIS-TLIF or O-TLIF does not overcome specific patient factors to mitigate clinical success or failure in terms of the intermediate-term PROs associated with 1- to 2-level lumbar fusion surgical procedures for degenerative pathologies.

Allogeneic blood transfusions and infection risk in lumbar spine surgery: An American College of Surgeons National Surgery Quality Improvement Program Study.

BACKGROUND: Allogenic blood transfusions can lead to immunomodulation. Our purpose was to investigate whether perioperative transfusions were associated with postoperative infections and any other adverse events (AEs), after adjusting for potential confounding factors, following common elective lumbar spinal surgery procedures. STUDY DESIGN AND METHODS: We performed a multivariate, propensity-score matched, regression-adjusted retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program database between 2012 and 2016. All lumbar spinal surgery procedures were identified (n = 174,891). A transfusion group (perioperative transfusion within 72 h before, during, or after principal surgery; n = 1992) and a control group (no transfusion; n = 1992) were formed. Following adjustment for between-group baseline features, adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) were calculated using a multivariate logistic regression model for any surgical site infection (SSI), superficial SSI, deep SSI, wound dehiscence, pneumonia, urinary tract infection, sepsis, any infection, mortality, and any AEs. RESULTS: Transfusion was associated with an increased risk of each specific infection, mortality, and any AEs. Statistically significant between-group differences were demonstrated with respect to any SSI (aOR: 1.48; 95% CI: 1.01-2.16), deep SSI (aOR: 1.66; 95% CI: 0.98-2.85), sepsis (aOR: 2.69; 95% CI: 1.43-5.03), wound dehiscence (aOR: 2.27; 95% CI: 0.86-6.01), any infection (aOR: 1.46; 95% CI: 1.13-1.88), any AEs (aOR: 1.80; 95% CI: 1.48-2.18), and mortality (aOR: 2.17; 95% CI: 0.77-6.36). CONCLUSION: We showed an association between transfusion and infection in lumbar spine surgery after adjustment for various applicable covariates. Sepsis had the highest association with transfusion. Our results reinforce a growing trend toward minimizing perioperative transfusions, which may lead to reduced infections following lumbar spine surgery.

National adverse event profile after lumbar spine surgery for lumbar degenerative disorders and comparison of complication rates between hospitals: a CSORN registry study.

OBJECTIVE: Previous works investigating rates of adverse events (AEs) in spine surgery have been retrospective, with data collection from administrative databases, and often from single centers. To date, there have been no prospective reports capturing AEs in spine surgery on a national level, with comparison among centers. METHODS: The Spine Adverse Events Severity system was used to define the incidence and severity of AEs after spine surgery by using data from the Canadian Spine Outcomes and Research Network (CSORN) prospective registry. Patient data were collected prospectively and during hospital admission for those undergoing elective spine surgery for degenerative conditions. The Spine Adverse Events Severity system defined minor and major AEs as grades 1-2 and 3-6, respectively. RESULTS: There were 3533 patients enrolled in this cohort. There were 85 (2.4%) individual patients with at least one major AE and 680 (19.2%) individual patients with at least one minor AE. There were 25 individual patients with 28 major intraoperative AEs and 260 patients with 275 minor intraoperative AEs. Postoperatively there were 61 patients with a total of 80 major AEs. Of the 487 patients with minor AEs postoperatively there were 698 total AEs. The average enrollment was 321 patients (range 47-1237 patients) per site. The rate of major AEs was consistent among sites (mean 2.9% ± 2.4%, range 0%-9.1%). However, the rate of minor AEs varied widely among sites-from 7.9% to 42.5%, with a mean of 18.8% ± 9.7%. The rate of minor AEs varied depending on how they were reported, with surgeon reporting associated with the lowest rates (p < 0.01). CONCLUSIONS: The rate of major AEs after lumbar spine surgery is consistent among different sites but the rate of minor AEs appears to vary substantially. The method by which AEs are reported impacts the rate of minor AEs. These data have implications for the detection and reporting of AEs and the design of strategies aimed at mitigating complications.

Factors associated with using an interbody fusion device for low-grade lumbar degenerative versus isthmic spondylolisthesis: a retrospective cohort study.

OBJECTIVE: Many studies have utilized a combined cohort of patients with degenerative spondylolisthesis (DS) and isthmic spondylolisthesis (IS) to evaluate indications and outcomes. Intuitively, these are very different populations, and rates, indications, and outcomes may differ. The goal of this study was to compare specific patient characteristics associated with the utilization of a posterior lumbar interbody device between cohorts of patients with DS and IS, as well as to compare rates of interbody device use and patient-rated outcomes at 1 year after surgical treatment. METHODS: The authors included patients who underwent posterior lumbar interbody fusion or instrumented posterolateral fusion for grade I or II DS or IS and had been enrolled in the Canadian Spine Outcomes and Research Network registry from 2009 to 2016. The outcome measures were score on the Oswestry Disability Index, scores for back pain and leg pain on the numeric rating scale, and mental component summary (MCS) score and physical component summary score on the 12-Item Short-Form Health Survey. Descriptive statistics were used to compare spondylolisthesis groups, logistic regression was used to compare interbody device use, and the chi-square test was used to compare the proportions of patients who achieved a minimal clinically important difference (MCID) at 1 year after surgery. RESULTS: In total, 119 patients had IS and 339 had DS. Patients with DS were more commonly women, older, less likely to smoke, and more likely to have neurogenic claudication and comorbidities, whereas patients with IS more commonly had radicular pain, neurological deficits, and worse back pain. Spondylolisthesis was more common at the L4-5 level in patients with DS and at the L5-S1 level in patients with IS. Similar proportions of patients had an interbody device (78.6% of patients with DS vs 82.4% of patients with IS, p = 0.429). Among patients with IS, factors associated with interbody device utilization were BMI ≥ 30 kg/m2 and increased baseline leg pain intensity. Factors associated with interbody device utilization in patients with DS were younger age, increased number of total comorbidities, and lower baseline MCS score. For each outcome measure, similar proportions of patients in the surgical treatment and spondylolisthesis groups achieved the MCID at 1 year after surgery. CONCLUSIONS: Although the demographic and patient characteristics associated with interbody device utilization differed between cohorts, similar proportions of patients attained clinically meaningful improvement at 1 year after surgery.

Using a national surgical database to predict complications following posterior lumbar surgery and comparing the area under the curve and F1-score for the assessment of prognostic capability.

BACKGROUND: With spinal surgery rates increasing in North America, models that are able to accurately predict which patients are at greater risk of developing complications are highly warranted. However, the previously published methods which have used large, multi-centre databases to develop their prediction models have relied on the receiver operator characteristics curve with the associated area under the curve (AUC) to assess their model's performance. Recently, it has been found that a precision-recall curve with the associated F1-score could provide a more realistic analysis for these models. PURPOSE: To develop a logistic regression (LR) model for the prediction of complications following posterior lumbar spine surgery and to then assess for any difference in performance of the model when using the AUC versus the F1-score. STUDY DESIGN: Retrospective review of a prospective cohort. PATIENT SAMPLE: The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) registry was used. All patients that underwent posterior lumbar spine surgery between 2005 to 2016 with appropriate data were included. OUTCOME MEASURES: Both the AUC and F1-score were utilized to assess the prognostic performance of the prediction model. METHODS: In order to develop the LR model used to predict a complication during or following spine surgery, 19 variables were selected by three orthopedic spine surgeons from the NSQIP registry. Two datasets were developed for this analysis: (1) an imbalanced dataset, which was taken directly from the NSQIP registry, and (2) a down-sampled set. The purpose of the down-sampled set was to balance the data in order to evaluate whether balancing the data had an effect on model performance. The AUC and F1-score were applied to both of these datasets. RESULTS: Within the NSQIP database, 52,787 spine surgery cases were identified of which only 10% of these cases had complications during surgery. Applying the LR model showed a large difference between the AUC (0.69) and the F1 score (0.075) on the imbalanced dataset. However, no major differences existed between the AUC and F1-score when the data was balanced and the LR model was reapplied (0.69 and 0.62, AUC and F1-score, respectively). CONCLUSIONS: The F1-score detected a drastically lower performance for the prediction of complications when using the imbalanced data, but detected a performance similar to the AUC level when balancing techniques were utilized for the dataset. This difference is due to a low precision score when many false positive classifications are present, which is not identified when using the AUC value. This lowers the utility of the AUC score, as many of the datasets used in medicine are imbalanced. Therefore, we recommend using the F1-score on large, prospective databases when the data is imbalanced with a large amount of true negative classifications.

Comparison of Clinical Outcomes Between Posterior Instrumented Fusion With and Without Interbody Fusion for Isthmic Spondylolisthesis.

STUDY DESIGN: A multicenter ambispective study using the Canadian Spine Outcomes and Research Network to compare clinical outcomes in adult patients with isthmic spondylolisthesis who received surgery. OBJECTIVE: The purpose of this study is to compare 1-year postoperative clinical outcomes between posterior instrumented fusion with and without interbody fusion in patients with isthmic spondylolisthesis. SUMMARY OF BACKGROUND DATA: Despite the increased use of interbody fusion in patients with isthmic spondylolisthesis, clinical superiority has not been demonstrated. It remains unclear what the optimal surgical approach is for this population. MATERIALS AND METHODS: The primary outcome was changed in leg pain at 1 year. Secondary outcomes were changed in Oswestry Disability Index, Short Form-12 Physical Component Score, and back pain at 1-year postoperative follow-up, estimated intraoperative blood loss, length of surgery, length of stay, number of transfusions, and adverse events. Descriptive statistics, Student t test, χ2 test, and stepwise multivariable regression were used for analysis. RESULTS: In total, 300 patients were included in this study. Of the 300 patients, 252 received posterolateral instrumented fusion with interbody fusion and 48 received posterolateral instrumented fusion alone. There were no significant differences in primary and secondary clinical outcomes at 1-year postoperative follow-up between the 2 groups. There were no significant differences in estimated blood loss (441 vs. 356 mL), length of surgery (210 vs. 224 min), length of stay (4 vs. 4 d), rate of transfusions (5.6% vs. 8.3%), and number of adverse events (33% vs. 23%) between patients who received interbody fusion and patients who did not. The addition of interbody fusion was not a significant variable for primary and secondary clinical outcomes in the stepwise multivariable regression analysis. CONCLUSIONS: There were no significant differences in clinical outcomes at 1 year or in the number of early complications between patients who received posterolateral fusion or posterior/transformational lumbar interbody fusion. LEVEL OF EVIDENCE: Level III.

A Comparison of Patient and Surgeon Expectations of Spine Surgical Outcomes.

STUDY DESIGN: Ambispective cohort study. OBJECTIVE: Limited data exists comparing surgeon and patient expectations of outcome following spine surgery. The objective of this study was to elicit whether any differences exist between patient and surgeon expectations for common spine surgeries. METHODS: Ten common age-appropriate clinical scenarios were generated and sent to Canadian spine surgeons to determine surgeon expectations for standard spine surgeries. Patients in the Canadian Spine Outcomes and Research Network (CSORN) registry matching the clinical scenarios were identified. Aggregated patient expectations were compared with surgeon responses for each scenario. A χ2 analysis was then completed to determine discrepancies between surgeon and patient expectations for each scenario. RESULTS: A total of 51 Canadian spine surgeons completed the survey on surgical expectations. A total of 919 patients from multiple centers were identified within the CSORN database that matched the clinical scenarios. Our results demonstrated that patients tend to be more optimistic about the expected outcomes of surgery compared with the treating surgeon. The majority of patients in all clinical scenarios anticipated improvement in back or neck pain after surgery, which differed from surgeon expectations. Results also highlighted the effect of patient age on both patient and surgeon expectations. Discrepancies between patient and surgeon expectations were higher for older patients. CONCLUSION: We present data on patient and surgeon expectations for spine surgeries and show that differences exist particularly concerning the improvement of neck or back pain. Patient age plays a role in the agreement between the treating physicians and patients in regard to surgical expectations. The reasons for the discrepancies remain unclear.

Preoperative Factors Predict Postoperative Trajectories of Pain and Disability Following Surgery for Degenerative Lumbar Spinal Stenosis.

STUDY DESIGN: Longitudinal analysis of prospectively collected data. OBJECTIVE: Investigate potential predictors of poor outcome following surgery for degenerative lumbar spinal stenosis (LSS). SUMMARY OF BACKGROUND DATA: LSS is the most common reason for an older person to undergo spinal surgery, yet little information is available to inform patient selection. METHODS: We recruited LSS surgical candidates from 13 orthopedic and neurological surgery centers. Potential outcome predictors included demographic, health, clinical, and surgery-related variables. Outcome measures were leg and back numeric pain rating scales and Oswestry disability index scores obtained before surgery and after 3, 12, and 24 postoperative months. We classified surgical outcomes based on trajectories of leg pain and a composite measure of overall outcome (leg pain, back pain, and disability). RESULTS: Data from 529 patients (mean [SD] age = 66.5 [9.1] yrs; 46% female) were included. In total, 36.1% and 27.6% of patients were classified as experiencing a poor leg pain outcome and overall outcome, respectively. For both outcomes, patients receiving compensation or with depression/depression risk were more likely, and patients participating in regular exercise were less likely to have poor outcomes. Lower health-related quality of life, previous spine surgery, and preoperative anticonvulsant medication use were associated with poor leg pain outcome. Patients with ASA scores more than two, greater preoperative disability, and longer pain duration or surgical waits were more likely to have a poor overall outcome. Patients who received preoperative chiropractic or physiotherapy treatment were less likely to report a poor overall outcome. Multivariable models demonstrated poor-to acceptable (leg pain) and excellent (overall outcome) discrimination. CONCLUSION: Approximately one in three patients with LSS experience a poor clinical outcome consistent with surgical non-response. Demographic, health, and clinical factors were more predictive of clinical outcome than surgery-related factors. These predictors may assist surgeons with patient selection and inform shared decision-making for patients with symptomatic LSS. LEVEL OF EVIDENCE: 2.