Low Household Income Increases Hospital Length of Stay and Decreases Home Discharge Rates in Lumbar Fusion

STUDY DESIGN

Retrospective Matched Cohort Study.

OBJECTIVES

Low median household income (MHI) has been correlated with worsened surgical outcomes, but few studies have rigorously controlled for demographic and medical factors at the patient level. This study isolates the relationship between MHI and surgical outcomes in a lumbar fusion cohort using coarsened exact matching.

METHODS

Patients undergoing single-level, posterior lumbar fusion at a single institution were consecutively enrolled and retrospectively analyzed (n = 4263). Zip code was cross-referenced to census data to derive MHI. Univariate regression correlated MHI to outcomes. Patients with low MHI were matched to those with high MHI based on demographic and medical factors. Outcomes evaluated included complications, length of stay, discharge disposition, 30- and 90 day readmissions, emergency department (ED) visits, reoperations, and mortality.

RESULTS

By univariate analysis, MHI was significantly associated with 30- and 90 day readmission, ED visits, reoperation, and non-home discharge, but not mortality. After exact matching (n = 270), low-income patients had higher odds of non-home discharge (OR = 2.5, P = .016) and higher length of stay (mean 100.2 vs 92.6, P = .02). There were no differences in surgical complications, ED visits, readmissions, or reoperations between matched groups.

CONCLUSIONS

Low MHI was significantly associated with adverse short-term outcomes from lumbar fusion. A matched analysis controlling for confounding variables uncovered longer lengths of stay and higher rates of discharge to post-acute care (vs home) in lower MHI patients. Socioeconomic disparities affect health beyond access to care, worsen surgical outcomes, and impose costs on healthcare systems. Targeted interventions must be implemented to mitigate these disparities.

Racial disparities in short-term spinal fusion outcomes across 4263 consecutive patients

OBJECTIVE

Race plays a salient role in access to surgical care. However, few investigations have assessed the impact of race within surgical populations after care has been delivered. The objective of this study was to employ an exact matching protocol to a homogenous population of spine surgery patients in order to isolate the relationships between race and short-term postoperative outcomes.

METHODS

In total, 4263 consecutive patients who underwent single-level, posterior-only lumbar fusion at a single multihospital academic medical center were retrospectively enrolled. Of these patients, 3406 patients self-identified as White and 857 patients self-identified as non-White. Outcomes were initially compared across all patients via logistic regression. Subsequently, White patients and non-White patients were exactly matched on the basis of key demographic and health characteristics (1520 matched patients). Outcome disparities were evaluated between the exact-matched cohorts. Primary outcomes were readmissions, emergency department (ED) visits, reoperations, mortality, intraoperative complications, and discharge disposition.

RESULTS

Before matching, non-White patients were less likely to be discharged home and more likely to be readmitted, evaluated in the ED, and undergo reoperation. After matching, non-White patients experienced higher rates of nonhome discharge, readmissions, and ED visits. Non-White patients did not have more surgical complications either before or after matching.

CONCLUSIONS

Between otherwise similar cohorts of spinal fusion cases, non-White patients experienced unfavorable discharge disposition and higher risk of multiple adverse postoperative outcomes. However, these findings were not accounted for by differences in surgical complications, suggesting that structural factors underlie the observed disparities.

Association Between Race and Short-Term Outcomes Across 3988 Consecutive Single-Level Spinal Fusions

BACKGROUND AND OBJECTIVES

Race has implications for access to medical care. However, the impact of race, after access to care has been attained, remains poorly understood. The objective of this study was to isolate the relationship between race and short-term outcomes across patients undergoing a single, common neurosurgical procedure.

METHODS

In this retrospective cohort study, 3988 consecutive patients undergoing single-level, posterior-only open lumbar fusion at a single, multihospital, academic medical center were enrolled over a 6-year period. Among them, 3406 patients self-identified as White, and 582 patients self-identified as Black. Outcome disparities between all White patients vs all Black patients were estimated using logistic regression. Subsequently, coarsened exact matching controlled for outcome-mitigating factors; White and Black patients were exact-matched 1:1 on key demographic and health characteristics (matched n = 1018). Primary outcomes included 30-day and 90-day hospital readmissions, emergency department (ED) visits, reoperations, mortality, discharge disposition, and intraoperative complication.

RESULTS

Before matching, Black patients experienced increased rate of nonhome discharge, readmissions, ED visits, and reoperations (all P < .001). After exact matching, Black patients were less likely to be discharged to home (odds ratio [OR] 2.68, P < .001) and had higher risk of 30-day and 90-day readmissions (OR 2.24, P < .001; OR 1.91, P < .001; respectively) and ED visits (OR 1.79, P = .017; OR 2.09, P < .001). Black patients did not experience greater risk of intraoperative complication (unintentional durotomy).

CONCLUSION

Between otherwise homogenous spinal fusion cohorts, Black patients experienced unfavorable short-term outcomes. These disparities were not explained by differences in intraoperative complications. Further investigation must characterize and mitigate institutional and societal factors that contribute to outcome disparities.

Quantifying a novel three-dimensional marker of scoliosis

BACKGROUND

Scoliosis causes abnormal spinal curvature and torsional rotation of the vertebrae and has implications for human suffering and societal cost. In differential geometry, Writhe describes three-dimensional curvature. Differential geometric quantities can inform better diagnostic metrics of scoliotic deformity. This evaluation could help physicians and researchers study scoliosis and determine treatments.

METHODS

Eight adult lumbar spine CT scans were analyzed in custom MATLAB programs to estimate Writhe and Cobb angle. Five patients exhibited scoliotic curvature, and three controls were asymptomatic. Vertebral centroids in three-dimensional space were determined, and Writhe was approximated. A T-test determined whether the affected spines had greater Writhe than the controls. Cohen's D test was used to determine effect size.

RESULTS

Writhe of scoliotic spines (5.4E-4 ± 2.7E-4) was significantly higher than non-scoliotic spines (8.2E-5 ± 1.1E-4; p = 0.008).

CONCLUSION

Writhe, a measure of curvature derived from 3D imaging, is significantly greater in scoliotic than in non-scoliotic spines. Future directions must include more subjects and examine writhe as a marker of scoliosis severity, progression, and response to treatment.

Single cell RNA sequencing reveals emergent notochord-derived cell subpopulations in the postnatal nucleus pulposus

Intervertebral disc degeneration is a leading cause of chronic low back pain. Cell-based strategies that seek to treat disc degeneration by regenerating the central nucleus pulposus (NP) hold significant promise, but key challenges remain. One of these is the inability of therapeutic cells to effectively mimic the performance of native NP cells, which are unique amongst skeletal cell types in that they arise from the embryonic notochord. In this study, we use single cell RNA sequencing to demonstrate emergent heterogeneity amongst notochord-derived NP cells in the postnatal mouse disc. Specifically, we established the existence of progenitor and mature NP cells, corresponding to notochordal and chondrocyte-like cells, respectively. Mature NP cells exhibited significantly higher expression levels of extracellular matrix (ECM) genes including aggrecan, and collagens II and VI, along with elevated transforming growth factor-beta and phosphoinositide 3 kinase-protein kinase B signaling. Additionally, we identified Cd9 as a novel surface marker of mature NP cells, and demonstrated that these cells were localized to the NP periphery, increased in numbers with increasing postnatal age, and co-localized with emerging glycosaminoglycan-rich matrix. Finally, we used a goat model to show that Cd9+ NP cell numbers decrease with moderate severity disc degeneration, suggesting that these cells are associated with maintenance of the healthy NP ECM. Improved understanding of the developmental mechanisms underlying regulation of ECM deposition in the postnatal NP may inform improved regenerative strategies for disc degeneration and associated low back pain.

Relationship Between Comorbidity Burden and Short-Term Outcomes Across 4680 Consecutive Spinal Fusions

OBJECTIVE

Preoperative management requires the identification and optimization of modifiable medical comorbidities, though few studies isolate comorbid status from related patient-level variables. This study evaluates Charlson Comorbidity Index (CCI)-an easily derived measure of aggregate medical comorbidity-to predict outcomes from spinal fusion surgery. Coarsened exact matching is employed to control for key patient characteristics and isolate CCI.

METHODS

We retrospectively assessed 4680 consecutive patients undergoing single-level, posterior-only lumbar fusion at a single academic center. Logistic regression evaluated the univariate relationship between CCI and patient outcomes. Coarsened exact matching generated exact demographic matches between patients with high comorbid status (CCI >6) or no medical comorbidities (matched n = 524). Patients were matched 1:1 on factors associated with surgical outcomes, and outcomes were compared between matched cohorts. Primary outcomes included surgical complications, discharge status, 30- and 90-day risk of readmission, emergency department (ED) visits, reoperation, and mortality.

RESULTS

Univariate regression of increasing CCI was significantly associated with non-home discharge, as well as 30- and 90-day readmission, ED visits, and mortality (all P < 0.05). Subsequent isolation of comorbidity between otherwise exact-matched cohorts found comorbid status did not affect readmissions, reoperations, or mortality; high CCI score was significantly associated with non-home discharge (OR = 2.50, P < 0.001) and 30-day (OR = 2.44, P = 0.02) and 90-day (OR = 2.29, P = 0.008) ED evaluation.

CONCLUSIONS

Comorbidity, measured by CCI, did not increase the risk of readmission, reoperation, or mortality. Single-level, posterior lumbar fusions may be safe in appropriately selected patients regardless of comorbid status. Future studies should determine whether CCI can guide discharge planning and postoperative optimization.

The Impact of Neighborhood Socioeconomic Disadvantage on Operative Outcomes after Single-Level Lumbar Fusion

INTRODUCTION

The relationship between socioeconomic status and neurosurgical outcomes has been investigated with respect to insurance status or median household income, but few studies have considered more comprehensive measures of socioeconomic status. This study examines the relationship between Area Deprivation Index (ADI), a comprehensive measure of neighborhood socioeconomic disadvantage, and short-term postoperative outcomes after lumbar fusion surgery.

METHODS

1861 adult patients undergoing single-level, posterior-only lumbar fusion at a single, multihospital academic medical center were retrospectively enrolled. An ADI matching protocol was used to identify each patient's 9-digit zip code and the zip code-associated ADI data. Primary outcomes included 30- and 90-day readmission, emergency department visits, reoperation, and surgical complication. Coarsened exact matching was used to match patients on key demographic and baseline characteristics known to independently affect neurosurgical outcomes. Odds ratios (ORs) were computed to compare patients in the top 10% of ADI versus lowest 40% of ADI.

RESULTS

After matching (n = 212), patients in the highest 10% of ADI (compared to the lowest 40% of ADI) had significantly increased odds of 30- and 90-day readmission (OR = 5.00, P < 0.001 and OR = 4.50, P < 0.001), ED visits (OR = 3.00, P = 0.027 and OR = 2.88, P = 0.007), and reoperation (OR = 4.50, P = 0.039 and OR = 5.50, P = 0.013). There was no significant association with surgical complication (OR = 0.50, P = 0.63).

CONCLUSIONS

Among otherwise similar patients, neighborhood socioeconomic disadvantage (measured by ADI) was associated with worse short-term outcomes after single-level, posterior-only lumbar fusion. There was no significant association between ADI and surgical complications, suggesting that perioperative complications do not explain the socioeconomic disparities in outcomes.

Varying Degree of Overlap Following the Critical Steps of Lumbar Fusion and Short-term Outcomes

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The present study analyzes the impact of end-overlap on short-term outcomes after single-level, posterior lumbar fusions.

SUMMARY OF BACKGROUND DATA

Few studies have evaluated how "end-overlap" (i.e., surgical overlap after the critical elements of spinal procedures, such as during wound closure) influences surgical outcomes.

METHODS

Retrospective analysis was performed on 3563 consecutive adult patients undergoing single-level, posterior-only lumbar fusion over a 6-year period at a multi-hospital university health system. Exclusion criteria included revision surgery, missing key health information, significantly elevated body mass index (>70), non-elective operations, non-general anesthesia, and unclean wounds. Outcomes included 30-day emergency department visit, readmission, reoperation, morbidity, and mortality. Univariate analysis was carried out on the sample population, then limited to patients with end-overlap. Subsequently, patients with the least end-overlap were exact-matched to patients with the most. Matching was performed based on key demographic variables-including sex and comorbid status-and attending surgeon, and then outcomes were compared between exact-matched cohorts.

RESULTS

Among the entire sample population, no significant associations were found between the degree of end-overlap and short-term adverse events. Limited to cases with any end-overlap, increasing overlap was associated with increased 30-day emergency department visits ( P =0.049) but no other adverse outcomes. After controlling for confounding variables in the demographic-matched and demographic/surgeon-matched analyses, no differences in outcomes were observed between exact-matched cohorts.

CONCLUSIONS

The degree of overlap after the critical steps of single-level lumbar fusion did not predict adverse short-term outcomes. This suggests that end-overlap is a safe practice within this surgical population.

A Randomized Controlled Trial to Assess the Impact of Enhanced Recovery After Surgery on Patients Undergoing Elective Spine Surgery

OBJECTIVE

To conduct a prospective, randomized controlled trial (RCT) of an enhanced recovery after surgery (ERAS) protocol in an elective spine surgery population.

BACKGROUND

Surgical outcomes such as length of stay (LOS), discharge disposition, and opioid utilization greatly contribute to patient satisfaction and societal healthcare costs. ERAS protocols are multimodal, patient-centered care pathways shown to reduce postoperative opioid use, reduced LOS, and improved ambulation; however, prospective ERAS data are limited in spine surgery.

METHODS

This single-center, institutional review board-approved, prospective RCT-enrolled adult patients undergoing elective spine surgery between March 2019 and October 2020. Primary outcomes were perioperative and 1-month postoperative opioid use. Patients were randomized to ERAS (n=142) or standard-of-care (SOC; n=142) based on power analyses to detect a difference in postoperative opioid use.

RESULTS

Opioid use during hospitalization and the first postoperative month was not significantly different between groups (ERAS 112.2 vs SOC 117.6 morphine milligram equivalent, P =0.76; ERAS 38.7% vs SOC 39.4%, P =1.00, respectively). However, patients randomized to ERAS were less likely to use opioids at 6 months postoperatively (ERAS 11.4% vs SOC 20.6%, P =0.046) and more likely to be discharged to home after surgery (ERAS 91.5% vs SOC 81.0%, P =0.015).

CONCLUSION

Here, we present a novel ERAS prospective RCT in the elective spine surgery population. Although we do not detect a difference in the primary outcome of short-term opioid use, we observe significantly reduced opioid use at 6-month follow-up as well as an increased likelihood of home disposition after surgery in the ERAS group.

Single Cell RNA Sequencing Reveals Emergent Notochord-Derived Cell Subpopulations in the Postnatal Nucleus Pulposus

Intervertebral disc degeneration is a leading cause of chronic low back pain. Cell-based strategies that seek to treat disc degeneration by regenerating the central nucleus pulposus hold significant promise, but key challenges remain. One of these is the inability of therapeutic cells to effectively mimic the performance of native nucleus pulposus cells, which are unique amongst skeletal cell types in that they arise from the embryonic notochord. In this study we use single cell RNA sequencing to demonstrate emergent heterogeneity amongst notochord-derived nucleus pulposus cells in the postnatal mouse disc. Specifically, we established the existence of early and late stage nucleus pulposus cells, corresponding to notochordal progenitor and mature cells, respectively. Late stage cells exhibited significantly higher expression levels of extracellular matrix genes including aggrecan, and collagens II and VI, along with elevated TGF-β and PI3K-Akt signaling. Additionally, we identified Cd9 as a novel surface marker of late stage nucleus pulposus cells, and demonstrated that these cells were localized to the nucleus pulposus periphery, increased in numbers with increasing postnatal age, and co-localized with emerging glycosaminoglycan-rich matrix. Finally, we used a goat model to show the Cd9+ nucleus pulposus cell numbers decrease with moderate severity disc degeneration, suggesting that these cells are associated with maintenance of the healthy nucleus pulposus extracellular matrix. Improved understanding of the developmental mechanisms underlying regulation of ECM deposition in the postnatal NP may inform improved regenerative strategies for disc degeneration and associated low back pain.

Comparison of Single-Level Posterior Cervical Foraminotomy to Anterior Cervical Discectomy and Fusion for Radiculopathy

BACKGROUND

Posterior cervical foraminotomy (PCF) and anterior cervical discectomy and fusion (ACDF) are 2 commonly used surgical approaches to address cervical radiculopathy. Demonstrating superiority in clinical outcomes and durability of one of the approaches could change clinical practice on a large scale. This is the largest reported single-institutional retrospective cohort of single-level PCFs compared with single-level ACDFs for cervical radiculopathy.

METHODS

Patients undergoing either ACDF or PCF between 2014 and 2021 were identified using Current Procedural Terminology codes. Medical records were reviewed for demographics, surgical characteristics, and reoperations. Statistical analysis included t tests for continuous characteristics and c2 testing for categorical characteristics.

RESULTS

In total, 236 single-level ACDFs and 138 single-level PCFs were included. There was no significant difference in age (51.0 vs 51.3 years), body mass index (BMI; 28.6 vs 28.1), or Charlson Comorbidity Index (1.89 vs 1.68) between patients who underwent ACDF and those who underwent PCF. There was no difference in the rate of reoperation (5.1% vs 5.1%), time to reoperation (247 vs 319 days), or reoperation for recurrent symptoms (1.7% vs 2.9%) for ACDF vs PCF. Hospital length of stay (LOS) was longer for ACDF compared with PCF (1.65 vs 1.35 days, P = 0.041), and the overall readmission rate after ACDF was 20.8% vs 10.9% after PCF (P = 0.014).

CONCLUSIONS

Overall reoperation rates or reoperation for recurrent symptoms between ACDF and PCF were not significantly different, demonstrating that either procedure effectively addresses the indication for surgery. There was a significantly longer LOS after ACDF than PCF, and readmission rates at 90 days and 1 year were higher after ACDF.

LEVEL OF EVIDENCE: 3

Neurosurgeons Deliver Similar Quality Care Regardless of First Assistant Type: Resident Physician Versus Non-Physician Surgical Assistant

OBJECTIVE

There are limited data evaluating the outcomes of attending neurosurgeons with different types of first assistants. This study considers a common neurosurgical procedure (single-level, posterior-only lumbar fusion surgery) and examines whether attending surgeons deliver equal patient outcomes, regardless of the type of first assistant (resident physician versus non-physician surgical assistant), among otherwise exact-matched patients.

METHODS

The authors retrospectively analyzed 3,395 adult patients undergoing single-level, posterior-only lumbar fusion at a single academic medical center. Primary outcomes included readmissions, emergency department (ED) visits, reoperation, and mortality within 30 and 90 days after surgery. Secondary outcome measures included discharge disposition, length of stay, and length of surgery. Coarsened exact matching was used to match patients on key demographics and baseline characteristics known to independently affect neurosurgical outcomes.

RESULTS

Among exact-matched patients (n = 1402) there was no significant difference in adverse postsurgical events (readmission, ED visits, reoperation, or mortality) within 30 days or 90 days of the index operation between patients who had resident physicians versus NPSAs as first assistants. Patients who had resident physicians as first assistants demonstrated a longer length of stay (mean 100.0 vs. 87.4 hours, p < 0.001) and a shorter duration of surgery (mean 187.4 vs. 213.8 minutes, p < 0.001). There was no significant difference between the two groups in the percentage of patients discharged home.

CONCLUSIONS

For single-level posterior spinal fusion, in the setting described, there are no differences in short-term patient outcomes delivered by attending surgeons assisted by resident physicians versus NPSAs.

Postoperative Outcomes and Resource Utilization Following Open vs Endoscopic Far Lateral Lumbar Discectomy

BACKGROUND

Operative approaches for far lateral disc herniation (FLDH) repair may be classified as open or minimally invasive. The present study aims to compare postoperative outcomes and resource utilization between patients undergoing open and endoscopic (one such minimally invasive approach) FLDH surgeries.

METHODS

A total of 144 consecutive adult patients undergoing FLDH repair at a single, university health system over an 8-year period (2013-2020) were retrospectively reviewed. Patients were divided into 2 cohorts: "open" (n = 92) and "endoscopic" (n = 52). Logistic regression was performed to evaluate the impact of procedural type on postoperative outcomes, and resource utilization metrics were compared between cohorts using χ ² test (for categorical variables) or t test (for continuous variables). Primary postsurgical outcomes included readmissions, reoperations, emergency department visits, and neurosurgery outpatient office visits within 90 days of the index operation. Primary resource utilization outcomes included total direct cost of the procedure and length of stay. Secondary measures included discharge disposition, operative length, and duration of follow-up.

RESULTS

No differences were observed in adverse postoperative events. Patients undergoing open FLDH surgery were more likely to attend outpatient visits within 30 days (P = 0.016). Although direct operating room cost was lower (P < 0.001) for open procedures, length of hospital stay was longer (P < 0.001). Patients undergoing open surgery also demonstrated less favorable discharge dispositions, longer operative length, and greater duration of follow-up.

CONCLUSIONS

While both procedure types represent viable options for FLDH, endoscopic surgeries appear to achieve comparable clinical outcomes with decreased perioperative resource utilization.

CLINICAL RELEVANCE

The present study suggests that endoscopic FLDH repairs do not lead to inferior outcomes but may decrease utilization of perioperative resources.

LEVEL OF EVIDENCE: 3

"July Effect" in Spinal Fusions: A Coarsened Exact-Matched Analysis

BACKGROUND

Few neurosurgical studies examine the July Effect within elective spinal procedures, and none uses an exact-matched protocol to rigorously account for confounders.

OBJECTIVE

To evaluate the July Effect in single-level spinal fusions, after coarsened exact matching of the patient cohort on key patient characteristics (including race and comorbid status) known to independently affect neurosurgical outcomes.

METHODS

Two thousand three hundred thirty-eight adult patients who underwent single-level, posterior-only lumbar fusion at a single, multicenter university hospital system were retrospectively enrolled. Primary outcomes included readmissions, emergency department visits, reoperation, surgical complications, and mortality within 30 days of surgery. Logistic regression was used to analyze month as an ordinal variable. Subsequently, outcomes were compared between patients with surgery at the beginning vs end of the academic year (ie, July vs April-June), before and after coarsened exact matching on key characteristics. After exact matching, 99 exactly matched pairs of patients (total n = 198) were included for analysis.

RESULTS

Among all patients, operative month was not associated with adverse postoperative events within 30 days of the index operation. Furthermore, patients with surgeries in July had no significant difference in adverse outcomes. Similarly, between exact-matched cohorts, patients in July were observed to have noninferior adverse postoperative events.

CONCLUSION

There was no evidence suggestive of a July Effect after single-level, posterior approach spinal fusions in our cohort. These findings align with the previous literature to imply that teaching hospitals provide adequate patient care throughout the academic year, regardless of how long individual resident physician assistants have been in their particular role.

Prone Zone 3 REBOA Rescue for Postoperative Hemorrhagic After Sacrococcygeal Tumor Resection

In this report, we describe a 41-year-old man who underwent resection of a large chordoma. During his post-operative recovery, he experienced delayed-onset non-compressive pelvic hemorrhage in the surgical resection bed resulting in nerve root compression. Zone 3 REBOA was prepositioned intra-operatively prior to placing the patient in the prone position for hematoma evacuation and exploration for surgical hemostasis. The balloon was completely inflated to facilitate exposure to the site of hemorrhage in this patient with a high risk for neurologic injury during this operative re-exploration.

Simple and actionable preoperative prediction of postoperative healthcare needs of single-level lumbar fusion patients

OBJECTIVE

Preoperative prediction of a patient's postoperative healthcare utilization is challenging, and limited guidance currently exists. The objective of the present study was to assess the capability of individual risk-related patient characteristics, which are available preoperatively, that may predict discharge disposition prior to lumbar fusion.

METHODS

In total, 1066 consecutive patients who underwent single-level, posterior-only lumbar fusion at a university health system were enrolled. Patients were prospectively asked 4 nondemographic questions from the Risk Assessment and Prediction Tool during preoperative office visits to evaluate key risk-related characteristics: baseline walking ability, use of a gait assistive device, reliance on community supports (e.g., Meals on Wheels), and availability of a postoperative home caretaker. The primary outcome was discharge disposition (home vs skilled nursing facility/acute rehabilitation). Logistic regression was performed to analyze the ability of each risk-related characteristic to predict likelihood of home discharge.

RESULTS

Regression analysis demonstrated that improved baseline walking ability (OR 3.17), ambulation without a gait assistive device (OR 3.13), and availability of a postoperative home caretaker (OR 1.99) each significantly predicted an increased likelihood of home discharge (all p < 0.0001). However, reliance on community supports did not significantly predict discharge disposition (p = 0.94).

CONCLUSIONS

Patient mobility and the availability of a postoperative caretaker, when determined preoperatively, strongly predict a patient's healthcare utilization in the setting of single-level, posterior lumbar fusion. These findings may help surgeons to streamline preoperative clinic workflow and support the patients at highest risk in a targeted fashion.

Effect of Household Income on Short-Term Outcomes Following Cerebellopontine Angle Tumor Resection

Objectives  The objective of this study is to elucidate the impact of income on short-term outcomes in a cerebellopontine angle (CPA) tumor resection population. Design  This is a retrospective regression analysis. Setting  This study was done at a single, multihospital, urban academic medical center. Participants  Over 6 years (from June 7, 2013, to April 24, 2019), 277 consecutive CPA tumor cases were reviewed. Main Outcome Measures  Outcomes studied included readmission, emergency department evaluation, unplanned return to surgery, return to surgery after index admission, and mortality. Univariate analysis was conducted among the entire population with significance set at a p -value <0.05. The population was divided into quartiles based on median household income and univariate analysis conducted between the lowest (quartile 1 [Q1]) and highest (quartile 4 [Q4]) socioeconomic quartiles, with significance set at a p -value <0.05. Stepwise regression was conducted to determine the correlations among study variables and to identify confounding factors. Results  Regression analysis of 273 patients demonstrated decreased rates of unplanned reoperation ( p  = 0.015) and reoperation after index admission ( p  = 0.035) at 30 days with higher standardized income. Logistic regression between the lowest (Q1) and highest (Q4) socioeconomic quartiles demonstrated decreased unplanned reoperation ( p  = 0.045) and decreasing but not significant reoperation after index admission ( p  = 0.15) for Q4 patients. No significant difference was observed for other metrics of morbidity and mortality. Conclusion  Higher socioeconomic status is associated with decreased risk of unplanned reoperation following CPA tumor resection.

Increasing Nonconcurrent Overlapping Surgery Is Not Associated With Outcome Changes in Lumbar Fusion

BACKGROUND

There remains a paucity of literature on the impact of overlap on neurosurgical patient outcomes. The purpose of the present study was to correlate increasing duration of surgical overlap with short-term patient outcomes following lumbar fusion.

METHODS

The present study retrospectively analyzed 1302 adult patients undergoing overlapping, single-level, posterior-only lumbar fusion within a single, multicenter, academic health system. Recorded outcomes included 30-day emergency department visits, readmission, reoperation, mortality, overall morbidity, and overall morbidity/surgical complications. The amount of overlap was calculated as a percentage of total overlap time. Comparison was made between patients with the most (top 10%) and least (bottom 40%) amount of overlap. Patients were then exact matched on key demographic factors but not by the attending surgeons. Subsequently, patients were exact matched by both demographic data and the attending surgeons. Univariate analysis was first carried out prior to matching and then on both the demographic-matched and surgeon-matched cohorts. Significance for all analyses was set at a P value of <0.05.

RESULTS

Within the whole population, increasing duration of overlap was not correlated with any short-term outcome (P = 0.41-0.91). After exact matching, patients with the most and least durations of overlap did not have significant differences with respect to any short-term outcomes (P = 0.34-1.00).

CONCLUSION

Increased amount of overlap is not associated with adverse short-term outcomes for single-level, posterior-only lumbar fusions.

CLINICAL RELEVANCE

The present results suggest that increasing the duration of overlap during lumbar fusion surgery does not lead to inferior outcomes.

LEVEL OF EVIDENCE: 3

Matched analysis of patient gender and meningioma resection outcomes

PURPOSE

Gender is a known social determinant of health (SDOH) that has been linked to neurosurgical outcome disparities. To improve quality of care, there exists a need to investigate the impact of gender on procedure-specific outcomes. The objective of this study was to assess the role of gender on short- and long-term outcomes following resection of meningiomas - the most common benign brain neoplasm of adulthood - between exact matched patient cohorts.

MATERIAL AND METHODS

All consecutive patients undergoing supratentorial meningioma resection (n = 349) at a single, university-wide health system over a 6-year period were analyzed retrospectively. Coarsened exact matching was employed to match patients on numerous key characteristics related to outcomes. Primary outcomes included readmission, ED visit, reoperation, and mortality within 30 and 90 days of surgery. Mortality and reoperation were also assessed during the entire follow-up period. Outcomes were compared between matched female and male cohorts.

RESULTS

Between matched cohorts, no significant difference was observed in morbidity or mortality at 30 days (p = 0.42-0.75), 90-days (p = 0.23-0.69), or throughout the follow-up period (p = 0.22-0.45). Differences in short-term mortality could not be assessed due to the low number of mortality events.

CONCLUSIONS

After matching on characteristics known to impact outcomes and when isolated from other SDOHs, gender does not independently affect morbidity and mortality following meningioma resection. Further research on the role of other SDOHs in this population is merited to better understand underlying drivers of disparity.

Socioeconomic Status Predicts Short-Term Emergency Department Utilization Following Supratentorial Meningioma Resection

Introduction By identifying drivers of healthcare disparities, providers can better support high-risk patients and develop risk-mitigation strategies. Household income is a social determinant of health known to contribute to healthcare disparities. The present study evaluates the impact of household income on short-term morbidity and mortality following supratentorial meningioma resection. Methods A total of 349 consecutive patients undergoing supratentorial meningioma resection over a six-year period (2013-2019) were analyzed retrospectively. Primary outcomes were unplanned hospital readmission, reoperations, emergency department (ED) visits, return to the operating room, and all-cause mortality within 30 days of the index operation. Standardized univariate regression was performed across the entire sample to assess the impact of household income on outcomes. Subsequently, outcomes were compared between the lowest (household income ≤ $51,780) and highest (household income ≥ $87,958) income quartiles. Finally, stepwise regression was executed to identify potential confounding variables. Results Across all supratentorial meningioma resection patients, lower household income was correlated with a significantly increased rate of 30-day ED visits (p = 0.002). Comparing the lowest and highest income quartiles, the lowest quartile was similarly observed to have a significantly higher rate of 30-day ED evaluation (p = 0.033). Stepwise regression revealed that the observed association between household income and 30-day ED visits was not affected by confounding variables. Conclusion This study suggests that household income plays a role in short-term ED evaluation following supratentorial meningioma resection.

Use of the LACE+ index to predict readmissions after single-level lumbar fusion

OBJECTIVE

Spinal fusion is one of the most common neurosurgical procedures. The LACE (length of stay, acuity of admission, Charlson Comorbidity Index [CCI] score, and emergency department [ED] visits within the previous 6 months) index was developed to predict readmission but has not been tested in a large, homogeneous spinal fusion population. The present study evaluated use of the LACE+ score for outcome prediction after lumbar fusion.

METHODS

LACE+ scores were calculated for all patients (n = 1598) with complete information who underwent single-level, posterior-only lumbar fusion at a single university medical system. Logistic regression was performed to assess the ability of the LACE+ score as a continuous variable to predict hospital readmissions within 30 days (30D), 30-90 days (30-90D), and 90 days (90D) of the index operation. Secondary outcome measures included ED visits and reoperations. Subsequently, patients with LACE+ scores in the bottom decile were exact matched to the patients with scores in the top 4 deciles to control for sociodemographic and procedural variables.

RESULTS

Among all patients, increased LACE+ score significantly predicted higher rates of readmissions in the 30D (p < 0.001), 30-90D (p = 0.001), and 90D (p < 0.001) postoperative windows. LACE+ score also predicted risk of ED visits at all 3 time points and reoperations at 30-90D and 90D. When patients with LACE+ scores in the bottom decile were compared with patients with scores in the top 4 deciles, higher LACE+ score predicted higher risk of readmissions at 30D (p = 0.009) and 90D (p = 0.005). No significant difference in hospital readmissions was observed between the exact-matched cohorts.

CONCLUSIONS

The present results suggest that the LACE+ score demonstrates utility in predicting readmissions within 30 and 90 days after single-level lumbar fusion. Future research is warranted that utilizes the LACE+ index to identify strategies to support high-risk patients in a prospective population.

Assessment of Gender Disparities in Short-Term and Long-Term Outcomes Following Posterior Fossa Tumor Resection

Introduction

The analysis of social determinants of health (SDOH) across different surgical populations is critical for the identification of health disparities and the development risk mitigation strategies among vulnerable patients. Research into the impact of gender on neurosurgical outcomes remains limited. The aim of the present study was to assess the effect of gender on outcomes, in a matched sample, following posterior fossa tumor resection, a high-risk neurosurgical procedure.

Methods

Two hundred seventy-eight consecutive patients undergoing posterior fossa tumor resection over a six-year period (June 07, 2013, to April 29, 2019) at a single academic medical system were retrospectively evaluated. Short-term outcomes included 30- and 90-day rates of emergency department (ED) visit, readmission, reoperation, and mortality. Long-term outcomes included mortality and reoperation for the duration of follow-up. Firstly, male and female patients in the entire pre-match sample were compared. Thereafter, coarsened exact matching was employed to control for confounding variables, matching male and female patients on key demographic factors - including history of prior surgery, median household income, and race, amongst others - and outcome comparison was repeated.

Results

In both the entire pre-match sample and matched cohort analyses, no significant differences in adverse postsurgical events were discerned between the female and male patients when evaluating 30-day or 90-day rates of ED visit, readmission, reoperation, and mortality. There were also no differences in reoperation or mortality for the duration of follow-up.

Conclusion

Gender does not appear to impact short- or long-term outcomes following posterior fossa tumor resection. As such, risk assessment and mitigation strategies in this population should focus on other SDOH. Further studies should assess the role of other SDOH within this population.

Overlap Before the Critical Step of Lumbar Fusion Does Not Lead to Increased Short-Term Morbidity

BACKGROUND

Few studies have assessed the impact of overlapping surgery during different timepoints of neurosurgical procedures.

OBJECTIVE

To evaluate the impact of overlap before the critical portion of surgery on short-term patient outcomes following lumbar fusion.

METHODS

In total, 3799 consecutive patients who underwent single-level, posterior-only lumbar fusion over 6 yr (2013-2019) at an academic hospital system were retrospectively studied. Outcomes included 30-d emergency department (ED) visit, readmission, reoperation, mortality, overall morbidity, and overall morbidity/surgical complications. Duration of overlap that occurred before the critical portion of surgery was calculated as a percentage of total beginning operative time. Univariate logistic regression was used to assess the impact of incremental 1% increases in the duration of overlap within the whole population and patients with beginning overlap. Subsequently, univariate analysis was used to compare exact matched patients with the least (bottom 40%) and most amounts of overlap (100% beginning overlap). Coarsened exact matching was used to match patients on key demographic factors, as well as attending surgeon. Significance was set at a P-value < .05.

RESULTS

Increased duration of beginning overlap was associated with a decrease in 30-d ED visit (P = .03) within all patients with beginning overlap, but not within the whole population undergoing lumbar fusion. Duration of beginning overlap was not associated with any other short-term morbidity or mortality outcome in either the whole population or patients with beginning overlap.

CONCLUSION

Increased duration of overlap before the critical step of surgery does not predict adverse short-term outcomes after single-level, posterior-only lumbar fusion.

Quality Initiative for the Administration of Vancomycin Prophylaxis in Penicillin-Allergic Neurosurgery Patients

Introduction

Vancomycin may be used as an alternative perioperative antibiotic for penicillin-allergic patients but follows a different infusion timing. At the institution presented herein, noncompliance with recommended vancomycin infusion timing has been hypothesized to contribute toward increased risk of surgical site infections and avoidable expenditures. The objective of this project was to utilize the Performance Improvement In Action methodology to identify, address, and solve the problem of vancomycin administration timing.

Methodology

This study took place at a multi-hospital, urban academic medical center. The protocol was developed by neurosurgery and anesthesia faculty, advanced practice providers, nursing, and pharmacy. Timing of the following points was recorded: initial order, order release, pharmacy verification, vancomycin infusion, and surgical incision. Fifty consecutive penicillin-allergic patients undergoing neurosurgical intervention were prospectively enrolled. Data comparison was made between the pilot and retrospective review cohorts.

Results

The pilot cohort achieved correct administration of vancomycin in 100% of cases. Average infusion start time prior to incision increased by 257% (p<0.0001).

Conclusions

This study demonstrates a departmental capacity for optimized timing of vancomycin infusions, in a budget- and workflow-neutral process, while reducing inappropriate administration. In the future, this protocol may be scaled to additional departments and institutions to appropriately and efficiently administer perioperative vancomycin and mitigate the risk for surgical site infections.

A Scoping Review of the Literature on the Relationship Between Social and Structural Determinants of Health and Neurosurgical Outcomes

In the present study, we performed a scoping review of the social and structural determinant of health (SSDOH)-related academic literature from neurosurgery. To identify the studies to include or consider for our systematic review, we worked with a medical librarian to develop detailed search strategies for each database. The search was limited to studies reported from January 1, 1990 to December 3, 2020. All reports retrieved from the database searches were exported and stored in EndNote X.9 bibliographic and reference manager (Clarivate, Philadelphia, Pennsylvania, USA). The reports were screened by title and abstract independently by two of the co-authors (G.G. and A.O.). Any disagreements between the 2 reviewers were resolved by a third reviewer, who was unaware of the decisions of the primary reviewers. The search resulted in 5940 studies. After exclusions during data extraction, 99 studies remained for the final analysis. From the 99 included studies, 6 social determinants were analyzed, with 3 studies evaluating the highest level of educational attainment, 14 studies evaluating gender, 52 studies evaluating race, and 41 studies evaluating economic stability. Studies referencing SSDOH were found in 8 subspecialties, with 40 studies in spine surgery, 4 studies in functional neurosurgery, 14 studies in vascular neurosurgery, 27 studies in cranial oncology, 5 studies in spinal oncology, 5 studies in pediatric neurosurgery, 1 study in trauma, and 3 studies in general/unspecified subspecialties. Research gaps included the remaining neurosurgical subspecialties and numerous other SSDOHs. These gaps should be areas of future study, with the goal of aligning research with new healthcare initiatives and ensuring consideration of SSDOHs.

Postoperative outcomes and the association with overlap before or after the critical step of lumbar fusion

OBJECTIVE

This study assesses how degree of overlap, either before or after the critical operative portion, affects lumbar fusion outcomes.

METHODS

The authors retrospectively studied 3799 consecutive patients undergoing single-level, posterior-only lumbar fusion over 6 years (2013-2019) at a university health system. Outcomes recorded within 30-90 and 0-90 postoperative days included emergency department (ED) visit, readmission, reoperation, overall morbidity, and mortality. Furthermore, morbidity and mortality were recorded for the duration of follow-up. The amount of overlap that occurred before or after the critical portion of surgery was calculated as a percentage of total beginning or end operative time. Subsequent to initial whole-population analysis, coarsened exact-matched cohorts of patients were created with the least and most amounts of either beginning or end overlap. Univariate analysis was performed on both beginning and end overlap exact-matched cohorts, with significance set at p < 0.05.

RESULTS

Equivalent outcomes were observed when comparing exact-matched patients. Among the whole population, the degree of beginning overlap was correlated with reduced ED visits within 30-90 and 0-90 days (p = 0.007, p = 0.009; respectively), and less 0-90 day morbidity (p = 0.037). Degree of end overlap was correlated with fewer 30-90 day ED visits (p = 0.015). When comparing only patients with overlap, degree of beginning overlap was correlated with fewer 0-90 day reoperations (p = 0.022), and no outcomes were correlated with degree of end overlap.

CONCLUSIONS

The degree of overlap before or after the critical step of surgery does not lead to worse outcomes after lumbar fusion.

Hypoxic Preconditioning Enhances Bone Marrow-Derived Mesenchymal Stem Cell Survival in a Low Oxygen and Nutrient-Limited 3D Microenvironment

OBJECTIVE

Skeletal tissues such as intervertebral disc and articular cartilage possess limited innate potential to regenerate, in part due to their avascularity and low cell density. Despite recent advances in mesenchymal stem cell (MSC)-based disc and cartilage regeneration, key challenges remain, including the sensitivity of these cells to in vivo microenvironmental stress such as low oxygen and limited nutrition. The objective of this study was to investigate whether preconditioning with hypoxia and/or transforming growth factor-β 3 (TGF-β3) can enhance MSC survival and extracellular matrix production in a low oxygen and nutrient-limited microenvironment.

DESIGN

MSCs from multiple bovine donors were preconditioned in monolayer in normoxia or hypoxia, with or without TGF-β3, and the global effects on gene expression were examined using microarrays. Subsequently, the effects of preconditioning on MSC survival and extracellular matrix production were examined using low oxygen and nutrient-limited pellet culture experiments.

RESULTS

Hypoxic preconditioning resulted in upregulation of genes associated with growth, cell-cell signaling, metabolism, and cell stress response pathways, and significantly enhanced MSC survival for all donors in low oxygen and nutrient-limited pellet culture. In contrast, TGF-β3 preconditioning diminished survival. The nature and magnitude of the effects of preconditioning with either hypoxia or TGF-β3 on glycosaminoglycan production were donor dependent.

CONCLUSIONS

These results strongly support the use of hypoxic preconditioning to improve postimplantation MSC survival in avascular tissues such as disc and cartilage.

Short-Term Impact of Bracing in Multi-Level Posterior Lumbar Spinal Fusion

BACKGROUND

Clinical practice in postoperative bracing after posterior lumbar spine fusion (PLF) is inconsistent between providers. This paper attempts to assess the effect of bracing on short-term outcomes related to safety, quality of care, and direct costs.

METHODS

Retrospective cohort analysis of consecutive patients undergoing multilevel PLF with or without bracing (2013-2017) was undertaken (n = 980). Patient demographics and comorbidities were analyzed. Outcomes assessed included length of stay (LOS), discharge disposition, quality-adjusted life years (QALY), surgical-site infection (SSI), total cost, readmission within 30 days, and emergency department (ED) evaluation within 30 days.

RESULTS

Amongst the study population, 936 were braced and 44 were not braced. There was no difference between the braced and unbraced cohorts regarding LOS (P = .106), discharge disposition (P = .898), 30-day readmission (P = .434), and 30-day ED evaluation (P = 1.000). There was also no difference in total cost (P = .230) or QALY gain (P = .740). The results indicate a significantly lower likelihood of SSI in the braced population (1.50% versus 6.82%, odds ratio = 0.208, 95% confidence interval = 0.057-0.751, P = .037). There was no difference in relevant comorbidities (P = .259-1.000), although the braced cohort was older than the unbraced cohort (63 versus 56 y, P = .003).

CONCLUSION

Bracing following multilevel posterior lumbar fixation does not alter short-term postoperative course or reduce the risk for early adverse events. Cost analysis show no difference in direct costs between the 2 treatment approaches. Short-term data suggest that removal of bracing from the postoperative regimen for PLF will not result in increased adverse outcomes.

Role of Race in Short-Term Outcomes for 1700 Consecutive Patients Undergoing Brain Tumor Resection

BACKGROUND

Access to medical care seems to be impacted by race. However, the effect of race on outcomes, once care has been established, is poorly understood.

PURPOSE

This study seeks to assess the influence of race on patient outcomes in a brain tumor surgery population.

IMPORTANCE AND RELEVANCE TO HEALTHCARE QUALITY

This study offers insights to if or how quality is impacted based on patient race, after care has been established. Knowledge of disparities may serve as a valuable first step toward risk factor mitigation.

METHODS

Patients differing in race, but matched on other outcomes affecting characteristics, were assessed for differences in outcomes subsequent to brain tumor resection. Coarsened exact matching was used to match 1700 supratentorial brain tumor procedures performed over a 6-year period at a single, multihospital academic medical center. Patient outcomes assessed included unplanned readmission, mortality, emergency department (ED) visits, and unanticipated return to surgery.

RESULTS

There was no significant difference in readmissions, mortality, ED visits, return to surgery after index admission, or return to surgery within 30 days between the two races.

CONCLUSION

This study suggests that race does not independently influence postsurgical outcomes but may instead serve as a proxy for other closely related demographics.

Overlapping single-level lumbar fusion and adverse short-term outcomes

OBJECTIVE

There is a paucity of research on the safety of overlapping surgery. The purpose of this study was to evaluate the impact of overlapping surgery on a homogenous population of exactly matched patients undergoing single-level, posterior-only lumbar fusion.

METHODS

The authors retrospectively analyzed case data of 3799 consecutive adult patients who underwent single-level, posterior-only lumbar fusion during a 6-year period (June 7, 2013, to April 29, 2019) at a multihospital university health system. Outcomes included 30-day emergency department (ED) visit, readmission, reoperation, and morbidity and mortality following surgery. Thereafter, coarsened exact matching was used to match patients with and without overlap on key demographic factors, including American Society of Anesthesiologists (ASA) class, Charlson Comorbidity Index (CCI) score, sex, and body mass index (BMI), among others. Patients were subsequently matched by both demographic data and by the specific surgeon performing the operation. Univariate analysis was carried out on the whole population, the demographically matched cohort, and the surgeon-matched cohort, with significance set at a p value < 0.05.

RESULTS

There was no significant difference in morbidity or any short-term outcome, including readmission, reoperation, ED evaluation, and mortality. Among the demographically matched cohort and surgeon-matched cohort, there was no significant difference in age, sex, history of prior surgery, ASA class, or CCI score. Overlapping surgery patients in both the demographically matched cohort and the matched cohort limited by surgeon had longer durations of surgery (p < 0.01), but no increased morbidity or mortality was noted. Patients selected for overlap had fewer prior surgeries and lower ASA class and CCI score (p < 0.01). Patients with overlap also had a longer duration of surgery (p < 0.01) but not duration of closure.

CONCLUSIONS

Exactly matched patients undergoing overlapping single-level lumbar fusion procedures had no increased short-term morbidity or mortality; however, duration of surgery was 20 minutes longer on average for overlapping operations. Further studies should assess long-term patient outcomes and the impact of overlap in this and other surgical procedures.

Household income is associated with return to surgery following discectomy for far lateral disc herniation

BACKGROUND

Numerous studies have demonstrated that household income is independently predictive of postsurgical morbidity and mortality, but few studies have elucidated this relationship in a purely spine surgery population. This study aims to correlate household income with adverse events after discectomy for far lateral disc herniation (FLDH).

METHODS

All adult patients (n = 144) who underwent FLDH surgery at a single, multihospital, 1659-bed university health system (2013-2020) were retrospectively analyzed. Univariate logistic regression was used to evaluate the relationship between household income and adverse postsurgical events, including unplanned hospital readmissions, ED visits, and reoperations.

RESULTS

Mean age of the population was 61.72 ± 11.55 years. Mean household income was $78,283 ± 26,996; 69 (47.9%) were female; and 126 (87.5%) were non-Hispanic white. Ninety-two patients underwent open and fifty-two underwent endoscopic FLDH surgery. Each additional dollar decrease in household income was significantly associated with increased risk of reoperation of any kind within 90-days, but not 30-days, after the index admission. However, household income did not predict risk of readmission or ED visit within either 30-days or 30-90-days post-surgery.

CONCLUSIONS

These findings suggest that household income may predict reoperation following FLDH surgery. Additional research is warranted into the relationship between household income and adverse neurosurgical outcomes.

Do-It-Yourself Augmented Reality Heads-Up Display (DIY AR-HUD): A Technical Note

BACKGROUND

We present a "Do-It-Yourself" method to build an affordable augmented reality heads-up display system (AR-HUD) capable of displaying intraoperative images. All components are commercially available products, which the surgeons may use in their own practice for educational and research purposes.

METHODS

Moverio BT 35-E smart glasses were connected to operating room imaging modalities (ie, fluoroscopy and 3D navigation platforms) via a high-definition multimedia interface (HDMI) converter, allowing for continuous high-definition video transmission. The addition of an HDMI transmitter-receiver makes the AR-HUD system wireless.

RESULTS

We used our AR-HUD system in 3 patients undergoing instrumented spinal fusion. AR-HUD projected fluoroscopy images onto the surgical field, eliminating shift of surgeon focus and procedure interruption, with only a 40- to 100-ms delay in transmission, which was not clinically impactful.

CONCLUSIONS

An affordable AR-HUD capable of displaying real-time information into the surgeon's view can be easily designed, built, and tested in surgical practice. As wearable heads-up display technology continues to evolve rapidly, individual components presented here may be substituted to improve its functionality and usability. Surgeons are in a unique position to conduct clinical testing in the operating room environment to optimize the augmented reality system for surgical use.

Social Determinants of Health and Neurosurgical Outcomes: Current State and Future Directions

The relationship between social determinants of health (SDOH) and neurosurgical outcomes has become increasingly relevant. To date, results of prior work evaluating the impact of social determinants in neurosurgery have been mixed, and the need for robust data on this subject remains. The present review evaluates how gender, race, and socioeconomic status (SES) influence outcomes following various brain tumor resection procedures. Results from a number of prior studies from the senior author's lab are summarized, with all data acquired using the EpiLog tool (Epilog Laser). Separate analyses were performed for each procedure, evaluating the unique, isolated impact of gender, race, and SES on outcomes. A comprehensive literature review identified any prior studies evaluating the influence of these SDOH on neurosurgical outcomes. The review presented herein suggests that the effect of gender and race on outcomes is largely mitigated when equal access to care is attained, and socioeconomic factors and comorbidities are controlled for. Furthermore, when patients are matched upon for a number of clinically relevant covariates, SES impacts postoperative mortality. Elucidation of this disparity empowers surgeons to initiate actionable change to equilibrate future outcomes.

Prediction of Adverse Outcomes Within 90 Days of Surgery in a Heterogeneous Orthopedic Surgery Population

INTRODUCTION

The LACE+ index has been shown to predict readmissions; however, LACE+ has not been validated for extended postoperative outcomes in an orthopedic surgery population. The purpose of this study is to examine whether LACE+ scores predict unplanned readmissions and adverse outcomes following orthopedic surgery. Use of the LACE1 index to proactively identify at-risk patients may enable actions to reduce preventable readmissions.

METHODS

LACE+ scores were retrospectively calculated at the time of discharge for all consecutive orthopedic surgery patients (n = 18,893) at a multicenter health system over 3 years (2016-2018). Coarsened exact matching was used to match patients based on characteristics not assessed in the LACE+ index. Outcome differences between matched patients in different LACE quartiles (i.e. Q4 vs. Q3, Q2, and Q1) were analyzed.

RESULTS

Higher LACE+ scores significantly predicted readmission and emergency department visits within 90 days of discharge and for 30-90 days after discharge for all studied quartiles. Higher LACE+ scores also significantly predicted reoperations, but only between Q4 and Q3 quartiles.

CONCLUSIONS

The results suggest that the LACE+ risk-prediction tool may accurately predict patients with a high likelihood of adverse outcomes after a broad array of orthopedic procedures.

Charlson Comorbidity Index score predicts adverse post-operative outcomes after far lateral lumbar discectomy

INTRODUCTION

The Charlson Comorbidity Index (CCI) score has been shown to predict 10-year all-cause mortality and post-neurosurgical complications but has never been examined in a far lateral disc herniation (FLDH) population. This study aims to correlate CCI score with adverse outcomes following FLDH repair.

PATIENTS AND METHODS

All patients (n = 144) undergoing discectomy for FLDH at a single, multihospital academic medical system (2013-2020) were retrospectively analyzed. CCI scores were determined for all patients. Univariate logistic regression was used to determine the ability of CCI score to predict adverse outcomes.

RESULTS

Mean age of the population was 61.72 ± 11.55 years, 69 (47.9%) were female, and 126 (87.5%) were non-Hispanic white. Patients underwent either open (n = 92) or endoscopic (n = 52) FLDH repair. Average CCI score among the patient population was 2.87 ± 2.42. Each additional point in CCI score was significantly associated with higher rates of readmission (p = 0.022, p = 0.014) in the 30-day and 30-90-day post-surgery window, respectively, and emergency department visits (p = 0.011) within 30-days. CCI score also predicted risk of reoperation of any kind (p = 0.013) within 30 days of the index operation. In addition, CCI score was predictive of risk of reoperation of any kind (p = 0.008, p < 0.001; respectively) and repeat neurosurgical intervention (p = 0.027, p = 0.027) within 30-days and 90-days of the index admission (either during the same admission or after discharge).

CONCLUSIONS

This study suggests that CCI score is a useful metric to predict of numerous adverse postoperative outcomes following discectomy for FLDH.

Reduction of Postoperative Opioid Use After Elective Spine and Peripheral Nerve Surgery Using an Enhanced Recovery After Surgery Program

OBJECTIVE

Enhanced recovery after surgery (ERAS) pathways have previously been shown to be feasible and safe in elective spinal procedures. As publications on ERAS pathways have recently emerged in elective neurosurgery, long-term outcomes are limited. We report on our 18-month experience with an ERAS pathway in elective spinal surgery.

METHODS

A historical cohort of 149 consecutive patients was identified as the control group, and 1,141 patients were prospectively enrolled in an ERAS protocol. The primary outcome was the need for opioid use one month postoperation. Secondary outcomes were opioid and nonopioid consumption on postoperative day (POD) 1, opioid use at three and six months postoperation, inpatient pain scores, patient satisfaction scores, postoperative Foley catheter use, mobilization/ambulation on POD0-1, length of stay, complications, and intensive care unit admissions.

RESULTS

There was significant reduction in use of opioids at one, three, and six months postoperation (38.6% vs 70.5%, P < 0.001, 36.5% vs 70.9%, P < 0.001, and 23.6% vs 51.9%, P = 0.008) respectively. Both groups had similar surgical procedures and demographics. PCA use was nearly eliminated in the ERAS group (1.4% vs 61.6%, P < 0.001). ERAS patients mobilized faster on POD0 compared with control (63.5% vs 20.7%, P < 0.001). Fewer patients in the ERAS group required postoperative catheterization (40.7% vs 32.7%, P < 0.001). The ERAS group also had decreased length of stay (3.4 vs 3.9 days, P = 0.020).

CONCLUSIONS

ERAS protocols for all elective spine and peripheral nerve procedures are both possible and effective. This standardized approach to patient care decreases opioid usage, eliminates the use of PCAs, mobilizes patients faster, and reduces length of stay.

Outcomes Following Discectomy for Far Lateral Disc Herniation Are Not Predicted by Obstructive Sleep Apnea

Introduction

Previous studies have demonstrated that obstructive sleep apnea (OSA) is associated with adverse postoperative outcomes, but few studies have examined OSA in a purely spine surgery population. This study investigates the association of the STOP-Bang questionnaire, a screening tool for undiagnosed OSA, with adverse events following discectomy for far lateral disc herniation (FLDH).

Methods

All adult patients (n = 144) who underwent FLDH surgery at a single, multihospital, academic medical center (2013-2020) were retrospectively enrolled. Univariate logistic regression was performed to evaluate the relationship between risk of OSA (low- or high-risk) according to STOP-Bang score and postsurgical outcomes, including unplanned hospital readmissions, ED visits, and reoperations.

Results

Ninety-two patients underwent open FLDH surgery, while 52 underwent endoscopic procedures. High risk of OSA according to STOP-Bang score did not predict risk of readmission, ED visit, outpatient office visit, or reoperation of any kind within either 30 days or 30-90 days of surgery. High risk of OSA also did not predict risk of reoperation of any kind or repeat neurosurgical intervention within 30 days or 90 days of the index admission (either during the same admission or after discharge).

Conclusion

The STOP-Bang questionnaire is not a reliable tool for predicting post-operative morbidity and mortality for FLDH patients undergoing discectomy. Additional studies are needed to assess the impact of OSA on morbidity and mortality in other spine surgery populations.

Composite Score for Outcome Prediction in Gynecologic Surgery Patients

BACKGROUND

The LACE+ index is a well-studied metric that compacts patient data in an effort to assess readmission risk.

PURPOSE

Assess the capacity of LACE+ scores for predicting short-term undesirable outcomes in an entire single-center population of patients undergoing gynecologic surgery.

IMPORTANCE AND RELEVANCE TO HEALTHCARE QUALITY

Proactive identification of high-risk patients, with tools such as the LACE+ index, may serve as the first step toward appropriately engaging resources for reducing readmissions.

METHODS

This study was a retrospective analysis that used coarsened exact matching. All gynecologic surgery cases over 2 years within a single health system (n = 12,225) were included for analysis. Outcomes of interest were unplanned readmission, emergency room (ER) evaluation, and return to surgery. Composite LACE+ scores were separated into quartiles and matched. For outcome comparison, matched patients were assessed by LACE+ quartile, using Q4 as the reference group.

RESULTS

Increasing LACE+ score reflected a higher rate of readmission (p = .003, p = .001) and visits to the ER at 30 postoperative days (p < .001).

CONCLUSION

The data presented here suggest that LACE+ index is a viable metric for patient outcome prediction following gynecologic surgery.

The impact of gender on long-term outcomes following supratentorial brain tumor resection

PURPOSE

Gender is a known social determinant of health which has been linked disparities in medical care. This study intends to assess the impact of gender on 90-day and long-term morbidity and mortality outcomes following supratentorial brain tumor resection in a coarsened-exact matched population.

MATERIALS AND METHODS

A total of 1970 consecutive patients at a single, university-wide health system undergoing supratentorial brain tumor resection over a six-year period (09 June 2013 to 26 April 2019) were analyzed retrospectively. Coarsened Exact Matching was employed to match patients on key demographic factors including history of prior surgery, smoking status, median household income, American Society of Anesthesiologists (ASA) grade, and Charlson Comorbidity Index (CCI), amongst others. Primary outcomes assessed included readmission, ED visit, unplanned reoperation, and mortality within 90 days of surgery. Long-term outcomes such as mortality and unplanned return to surgery during the entire follow-up period were also recorded.

RESULTS

Whole-population regression demonstrated significantly increased mortality throughout the entire follow-up period for the male cohort (p = 0.004, OR = 1.32, 95% CI = 1.09 - 1.59); however, no significant difference was found after coarsened exact matching was performed (p = 0.08). In both the whole-population regression and matched-cohort analysis, no significant difference was observed between gender and readmission, ED visit, unplanned reoperation, or mortality in the 90-day post-operative window, in addition to return to surgery after throughout the entire follow-up period.

CONCLUSION

After controlling for confounding variables, female birth gender did not significantly predict any difference in morbidity and mortality outcomes following supratentorial brain tumor resection. Difference between mortality outcomes in the pre-matched population versus the matched cohort suggests the need to better manage the underlying health conditions of male patients in order to prevent future disparities.

Duration of overlap during lumbar fusion does not predict outcomes

INTRODUCTION

The relationship between degree of surgical overlap and adverse postoperative outcomes remains poorly defined. This study aims to evaluate the impact of increasing duration of overlap on lumbar fusion outcomes.

PATIENTS AND METHODS

1302 adult patients undergoing overlapping surgery during single-level, posterior-only lumbar fusion at a multi-hospital, university health system were retrospectively assessed. Amount of overlap was calculated as a percentage of total overlap time. Patients were separated into groups with the most (top 10% of patients) and least amounts of overlap (bottom 40% of patients). Using Coarsened Exact Matching, patients with the most and least amounts of overlap were matched on demographics alone, then on both demographics and attending surgeon. Univariate analysis was performed for the whole population and both matched cohorts to compare amount of overlap to risk of adverse postsurgical events. Significance for all analyses was p-value < 0.05.

RESULTS

Duration of overlap was not associated with outcomes in the whole population, demographic-matched, or surgeon-matched analyses. Before exact matching, patients with the most amount of overlap had a significantly higher CCI score (p = 0.031) and shorter length of surgery (p = 0.006). In the demographic matched cohort, patients with increased overlap had a significantly shorter length of surgery (p = 0.001) only. In the surgeon matched cohort, there were no differences in length of surgery or CCI score.

CONCLUSIONS

Duration of surgical overlap does not predict adverse outcomes following lumbar fusion. These results suggest that overlapping surgery is a safe practice within this common neurosurgical indication.

Case Series of Ultrasonic Navigated Osteotomy for the Treatment of Spinal Chordomas

BACKGROUND

Chordomas present challenges for en bloc surgical resection, which optimally reduces local recurrence and increases patient survival. Navigated ultrasonic osteotomy, also known as piezosurgery, provides a distinct advantage for achieving negative margins after en bloc resection.

METHODS

Eight consecutive patients with chordomas (2 cervical, 3 lumbar, and 3 sacral) treated with navigated ultrasonic osteotomy to achieve en bloc resection were identified from our institutional spine tumor database (2016-2019) and retrospectively reviewed.

RESULTS

En bloc resection, with negative margins, was achieved in all cases. Two patients (25%) were women, and mean age at surgery was 44 ± 11 years. Median estimated blood loss was 1000 mL (interquartile range: 263-1500 mL). Median length of hospital stay was 10 days (interquartile range: 3-19.5 days). Two patients required a revision procedure. Two patients had complications requiring readmission within the 30-day postoperative window. Mean duration of follow-up for the cohort was 900 ± 554 days.

CONCLUSIONS

Navigated ultrasonic osteotomy is an effective surgical technique to achieve en bloc resection of chordomas with negative margins and disease-free survival. To date, this represents the first reported cohort of patients undergoing the procedure as described here. Future studies should include larger sample sizes for more robust clinical outcome data to further elucidate the benefits of piezosurgery for obtaining en bloc chordoma resection.

Predicting patient outcomes after far lateral lumbar discectomy

INTRODUCTION

The LACE+ (Length of Stay, Acuity of Admission, Charlson Comorbidity Index (CCI) Score, Emergency Department (ED) visits within the previous 6 months) index has never been tested in a purely spine surgery population. This study assesses the ability of LACE + to predict adverse patient outcomes following discectomy for far lateral disc herniation (FLDH).

PATIENTS AND METHODS

Data were obtained for patients (n = 144) who underwent far lateral lumbar discectomy at a single, multi-hospital academic medical center (2013-2020). LACE + scores were calculated for all patients with complete information (n = 100). The influence of confounding variables was assessed and controlled with stepwise regression. Logistic regression was used to test the ability of LACE + to predict risk of unplanned hospital readmission, ED visits, outpatient office visits, and reoperation after surgery.

RESULTS

Mean age of the population was 61.72 ± 11.55 years, 69 (47.9 %) were female, and 126 (87.5 %) were non-Hispanic white. Patients underwent either open (n = 92) or endoscopic (n = 52) surgery. Each point increase in LACE + score significantly predicted, in the 30-day (30D) and 30-90-day (30-90D) post-discharge window, higher risk of readmission (p = 0.005, p = 0.009; respectively) and ED visits (p = 0.045). Increasing LACE + also predicted, in the 30D and 90-day (90D) post-discharge window, risk of reoperation (p = 0.022, p = 0.016; respectively), and repeat neurosurgical intervention (p = 0.026, p = 0.026; respectively). Increasing LACE + score also predicted risk of reoperation (p = 0.011) within 30 days of initial surgery.

CONCLUSIONS

LACE + may be suitable for characterizing risk of adverse perioperative events for patients undergoing far lateral discectomy.

Patients undergoing overlapping posterior single-level lumbar fusion are not at greater risk for adverse 90-day outcomes

OBJECTIVE

This study evaluated overlapping surgery on long-term outcomes following elective, single-level lumbar fusion on exact matched patients undergoing surgery with or without overlap.

PATIENTS AND METHODS

3799 consecutive adult patients undergoing single-level, posterior-only lumbar fusion over a six-year period at a multi-hospital university health system were retrospectively followed. Reported outcomes included reoperation, emergency department (ED) visit, readmission, overall morbidity and mortality in the 90 days following surgery. Coarsened Exact Matching was used to match patients with and without overlap on key demographic factors. Patients were subsequently matched by both demographic data and by the attending surgeon performing the operation. Univariate analysis was carried out on the whole population, the demographic matched cohort, and demographic and surgeon matched cohort, with significance set at a p-value < 0.05.

RESULTS

Patients with overlap had a longer duration of surgery and were less likely to have an ED visit within 90 days of surgery (p < 0.03) but had no other significant differences. Within the demographic matched cohort and demographic/surgeon matched cohort, there was no significant difference in age, gender, history of prior surgery, ASA score, or CCI score, but patients with overlap had a longer duration of surgery (p < 0.01). Patients did not have significant differences with respect to any morbidity or mortality outcome in either the demographic or surgeon matched cohort.

CONCLUSIONS

Patients undergoing overlapping, single-level lumbar fusion were not at greater risk of long-term morbidity or mortality, despite having a significantly longer duration of surgery.

The influence of race on outcomes following pituitary tumor resection

OBJECTIVE

To assess the influence of race on short-term patient outcomes in a pituitary tumor surgery population.

PATIENTS AND METHODS

Coarsened exact matching was used to retrospectively analyze consecutive patients (n = 567) undergoing pituitary tumor resection over a six-year period (June 07, 2013 to April 29, 2019) at a single, multi-hospital academic medical center. Black/African American and white patients were exact matched based on twenty-nine (29) patient, procedure, and hospital characteristics. Matching characteristics included surgical costs, American Society of Anesthesiologists grade, duration of surgery, and Charlson Comorbidity Index, amongst others. Outcomes studied included unplanned 90-day readmission, emergency room (ER) evaluation, and unplanned reoperation.

RESULTS

Ninety-two (n = 92) patients were exact matched and analyzed. There was no significant difference in 90-day readmission (p = 0.267, OR (black/AA vs white) = 0.500, 95% CI = 0.131-1.653) or ER evaluation within 90 days (p = 0.092, OR = 3.000, 95% CI = 0.848-13.737) between the two cohorts. Furthermore, there was no significant difference in the rate of unplanned reoperation throughout the duration of the follow up period between matched black/African American and white patients (p = 0.607, OR = 0.750, 95% CI = 0.243-2.211).

CONCLUSION

This study suggests that the effect of race on post-operative outcomes is largely mitigated when equal access is attained, and when race is effectively isolated from socioeconomic factors and comorbidities in a population undergoing pituitary tumor resection.

The role of socioeconomic status on outcomes following cerebellopontine angle tumor resection

PURPOSE

It is well documented that the interaction between many social factors can affect clinical outcomes. However, the independent effects of economics on outcomes following surgery are not well understood. The goal of this study is to investigate the role socioeconomic status has on postoperative outcomes in a cerebellopontine angle (CPA) tumor resection population.

MATERIALS AND METHODS

Over 6 years (07 June 2013 to 24 April 2019), 277 consecutive CPA tumor cases were reviewed at a single, multihospital academic medical center. Patient characteristics obtained included median household income, Charlson Comorbidity Index (CCI), race, BMI, tobacco use, amongst 23 others. Outcomes studied included readmission, ED evaluation, unplanned return to surgery (during and after index admission), return to surgery after index admission, and mortality within 90 days, in addition to reoperation and mortality throughout the entire follow-up period. Univariate analysis was conducted amongst the entire population with significance set at a p value <0.05. The population was divided into quartiles based on median household income and univariate analysis conducted between the lowest (Q1) and highest (Q4) socioeconomic quartiles, with significance set at a p value <0.05. Stepwise regression was conducted to determine the correlations amongst study variables and identify confounding factors.

RESULTS

Regression analysis of 273 patients did not find household income to be associated with any of the long-term outcomes assessed. Similarly, a Q1 vs Q4 comparison did not yield significantly different odds of outcomes assessed.

CONCLUSION

Although not statistically significant, the odds ratios suggest socioeconomic status may have a clinically significant effect on postsurgical outcomes. Further studies in larger, matched populations are necessary to validate these findings.

Association of Police Transport With Survival Among Patients With Penetrating Trauma in Philadelphia, Pennsylvania

IMPORTANCE

Police in Philadelphia, Pennsylvania, routinely transport patients with penetrating trauma to nearby trauma centers. During the past decade, this practice has gained increased acceptance, but outcomes resulting from police transport of these patients have not been recently evaluated.

OBJECTIVE

To assess mortality among patients with penetrating trauma who are transported to trauma centers by police vs by emergency medical services (EMS).

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used the Pennsylvania Trauma Outcomes Study registry and included 3313 adult patients with penetrating trauma from January 1, 2014, to December 31, 2018. Outcomes were compared between patients transported by police (n = 1970) and patients transported by EMS (n = 1343) to adult level I and II trauma centers in Philadelphia.

EXPOSURES

Police vs EMS transport.

MAIN OUTCOMES AND MEASURES

The primary end point was 24-hour mortality. Secondary end points included death at multiple other time points. After whole-cohort regression analysis, coarsened exact matching was used to control for confounding differences between groups. Matching criteria included patient age, injury mechanism and location, Injury Severity Score (ISS), presenting systolic blood pressure, and Glasgow Coma Scale score. Subgroup analysis was performed among patients with low, moderate, or high ISS.

RESULTS

Of the 3313 patients (median age, 29 years [interquartile range, 23-40 years]) in the study, 3013 (90.9%) were men. During the course of the study, the number of police transports increased significantly (from 328 patients in 2014 to 489 patients in 2018; P = .04), while EMS transport remained unchanged (from 246 patients in 2014 to 281 patients in 2018; P = .44). On unadjusted analysis, compared with patients transported by EMS, patients transported by police were younger (median age, 27 years [interquartile range, 22-36 years] vs 32 years [interquartile range, 24-46 years]), more often injured by a firearm (1741 of 1970 [88.4%] vs 681 of 1343 [50.7%]), and had a higher median ISS (14 [interquartile range, 9-26] vs 10 [interquartile range, 5-17]). Patients transported by police had higher mortality at 24 hours than those transported by EMS (560 of 1970 [28.4%] vs 246 of 1343 [18.3%]; odds ratio, 1.86; 95% CI, 1.57-2.21; P < .001) and at all other time points. After coarsened exact matching (870 patients in each transport cohort), there was no difference in mortality at 24 hours (210 [24.1%] vs 212 [24.4%]; odds ratio, 0.95; 95% CI, 0.59-1.52; P = .91) or at any other time point. On subgroup analysis, patients with severe injuries transported by police were less likely to be dead on arrival compared with matched patients transported by EMS (64 of 194 [33.0%] vs 79 of 194 [40.7%]; odds ratio, 0.48; 95% CI, 0.24-0.94; P = .03).

CONCLUSIONS AND RELEVANCE

For patients with penetrating trauma in an urban setting, 24-hour mortality was not different for those transported by police vs EMS to a trauma center. Timely transport to definitive trauma care should be emphasized over medical capability in the prehospital management of patients with penetrating trauma.