The obesity paradox and ventriculoperitoneal shunting in aneurysmal subarachnoid hemorrhage patients undergoing microsurgical clipping.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) can be devastating. Identifying predisposing factors is paramount in reducing aSAH-related mortality. Obesity's negative impact on health is well-established. However, the controversial "obesity paradox" in neurosurgery suggests that obesity may confer a survival advantage in SAH. We hypothesized that obesity would have a negative impact on outcomes following surgical clipping in aSAH. METHODS: A single-institution retrospective review was performed of aSAH patients undergoing surgical clipping from 2017 to 2021. Demographics and clinically relevant variables were collected. Obesity was defined as body mass index >30. Primary outcome was death or severe disability (mRS 4-6) at last follow-up. Secondary outcome was VPS placement. Multivariable Cox proportional-hazards model identified predictors of poor outcome. Kaplan-Meier curves identified survivorship differences between obese and non-obese patients. RESULTS: Poor outcome occurred in 11 of 52 total patients (21.2 %). There were no differences in demographics or distribution of Hunt Hess (HH), modified Fisher Grade (mFG), or external ventricular drain (EVD) placement between obese and non-obese patients. On univariate analysis, hypertension, older age, and non-obesity were predictive of poor outcome. On multivariable analysis, only obesity remained significant, suggesting a protective effect from poor outcome (HR 0.45 [0.21-0.95], p = 0.037). VPS placement occurred in 6 (11.5 %) patients for which obesity was not a significant predictor. CONCLUSIONS: Obesity may have a protective effect against poor outcome following surgical clipping in aSAH. Additionally, obesity does not appear to increase rate of EVD conversion to VPS. Thus, our study suggests that obesity should not preclude patients from open surgical intervention when clinically appropriate.

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.

Prognosticators of Functional Outcome After Supratentorial Minimally Invasive Intracranial Hemorrhage Evacuation With Tubular Retractor Systems.

BACKGROUND AND OBJECTIVES: Prognosticators of good functional outcome after minimally invasive surgical (MIS) intracranial hemorrhage (ICH) evacuation are poorly defined. This study aims to investigate clinical and radiographic prognosticators of poor functional outcome after MIS evacuation of ICH with tubular retractor systems. METHODS: Single-center retrospective review of adult (age ≥18 years) patients who underwent surgical evacuation of a spontaneous supratentorial ICH evacuation using tubular retractors from 2013 to 2022 was performed. Clinical and radiographic factors, such as antiplatelet/anticoagulant use, initial NIH Stroke Scale, ICH score, premorbid modified Rankin Scale (mRS), intraventricular hemorrhage (IVH) severity according to the modified Graeb scale, and preoperative/postoperative ICH volume, were collected. The main outcome was poor functional outcome, defined as mRS score of 4-6 within 1 year postoperatively. RESULTS: Eighty-eight patients were included. Clinical follow-up data were available for 64 (73%) patients. Of those, 43 (67%) had a poor functional outcome. On multivariate Cox regression, postoperative ICH volume ≥15 mL (hazard ratio [HR] = 2.46 [95% CI: 1.25-4.87]; P = .010) and higher modified Graeb score (HR = 1.04 [95% CI: 1-1.1]; P = .035] significantly increased the risk of poor functional outcome. Elevated postoperative ICH volume was predicted by the presence of lobar ICH (vs nonlobar, OR = 3.32 [95% CI: 1.01-11.55]; P = .043) and higher preoperative ICH volume (OR = 1.05 [1.02-1.08]; P < .001). A minimum of 60% ICH evacuation yielded an improvement in mRS 4-6 rates (HR 0.3 [95% CI: 0.1-0.8], P = .013). In patients without IVH and with a >80% ICH evacuation, the rate of mRS 4-6 was 42% compared with 67% in the whole patient sample ( P = .017). CONCLUSION: Increased IVH volumes and residual postoperative ICH volumes are associated with poor functional outcome after MIS ICH evacuation. Postoperative ICH volume was associated with lobar ICH location as well as preoperative ICH volume. These factors may help to prognosticate patient outcomes and improve selection criteria for MIS ICH evacuation techniques.

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.

Flow diversion for the treatment of intracranial bifurcation aneurysms: a systematic review and meta-analysis.

BACKGROUND: Flow diversion (FD: flow diversion, flow diverter) is an endovascular treatment for many intracranial aneurysm types; however, limited reports have explored the use of FDs in bifurcation aneurysm management. We analyzed the safety and efficacy of FD for the management of intracranial bifurcation aneurysms. METHODS: A systematic review identified original research articles that used FD for treating intracranial bifurcation aneurysms. Articles with >4 patients that reported outcomes on the use of FDs for the management of bifurcation aneurysms along the anterior communicating artery (AComA), internal carotid artery terminus (ICAt), basilar apex (BA), or middle cerebral artery bifurcation (MCAb) were included. Meta-analysis was performed using a random effects model. RESULTS: 19 studies were included with 522 patients harboring 534 bifurcation aneurysms (mean size 9 mm, 78% unruptured). Complete aneurysmal occlusion rate was 68% (95% CI 58.7% to 76.1%, I2=67%) at mean angiographic follow-up of 16 months. Subgroup analysis of FD as a standalone treatment estimated a complete occlusion rate of 69% (95% CI 50% to 83%, I2=38%). The total complication rate was 22% (95% CI 16.7% to 28.6%, I2=51%), largely due to an ischemic complication rate of 16% (95% CI 10.8% to 21.9%, I2=55%). The etiologies of ischemic complications were largely due to jailed artery hypoperfusion (47%) and in-stent thrombosis (38%). 7% of patients suffered permanent symptomatic complications (95% CI 4.5% to 9.8%, I2=6%). CONCLUSION: FD treatment of bifurcation aneurysms has a modest efficacy and relatively unfavorable safety profile. Proceduralists may consider reserving FD as a treatment option if no other surgical or endovascular therapy is deemed feasible.

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.

Characterizing the Next Generation of Neurosurgeons: A Descriptive Analysis and Publicly Available Web Application of Neurosurgery Residency Programs' Website Data.

OBJECTIVE: Neurosurgery program websites serve as a valuable resource for applicants. However, each website exists in isolation, and it can be difficult to understand the general trends in U.S. neurosurgery resident demographics. In the present study, we collected data from program websites and analyzed the trends in the demographics of the current U.S. neurosurgery residents. METHODS: We used a program list obtained from the American Association of Medical Colleges Electronic Residency Application System to extract data from the current resident complement listed in each program's website, including program, year in program, medical school, sex (male vs. female), graduate and/or PhD degrees, and assessed the trends during 7 years of resident data using linear regression. RESULTS: We identified 116 neurosurgery residency programs in the United States, with 111 providing information on their current resident complement, yielding a dataset of 1599 residents. Of these 1599 residents, 348 (22%) were female, 301 (19%) had a graduate degree in addition to an MD or DO degree, 151 (9.4%) had a PhD degree, 300 (19%) had matched at the program affiliated with their medical school, and 121 (7.6%) had graduated from a foreign medical school. The proportion of matriculating female residents had increased an average of 2.1% annually (95% confidence interval, 0.6%-3.7%) from 2015 to 2021. The other demographic data had not changed significantly during the same period. CONCLUSIONS: In addition to summarizing the current resident demographics, our analysis identified a significant increase in the proportion of female residents between 2015 (15.1%) and 2021 (25.6%). This publicly available dataset should enable additional analyses of the evolution of neurosurgery resident demographics.

Interhemispheric gravity-assisted approach for microsurgical resection of a splenium arteriovenous malformation.

The parietal interhemispheric approach employing gravity retraction with skeletonization of bridging veins provides an excellent operative window for safe, curative resection of splenial arteriovenous malformations.

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 postsurgery. 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.

Impact of the 2016 American College of Surgeons Guideline Revision on Overlapping Lumbar Fusion Cases at a Large Academic Medical Center.

OBJECTIVE: The American College of Surgeons (ACS) updated its guidelines on overlapping surgery in 2016. The objective was to examine differences in postoperative outcomes after overlapping surgery either pre-ACS guideline revision or post-guideline revision, in a coarsened exact matching sample. METHODS: A total of 3327 consecutive adult patients undergoing single-level posterior lumbar fusion from 2013 to 2019 were retrospectively analyzed. Patients were separated into a pre-ACS guideline revision cohort (surgery before April 2016) or a post-guideline revision cohort (surgery after October 2016) for comparison. The primary outcomes were proportion of cases performed with any degree of overlap, and adverse events including 30-day and 90-day rates of readmission, reoperation, emergency department visit, morbidity, and mortality. Subsequently, coarsened exact matching was used among overlapping surgery patients only to assess the impact of the ACS guideline revision on overlapping outcomes, and controlling for attending surgeon and key patient characteristics known to affect surgical outcomes. RESULTS: After the implementation of the ACS guidelines, fewer cases were performed with overlap (22.0% vs. 53.7%; P < 0.001). Patients in the post-ACS guideline revision cohort experienced improved rates of readmission and reoperation within 30 and 90 days. However, when limited to overlapping cases only, no differences were observed in overlap outcomes pre-ACS versus post-ACS guideline revision. Similarly, when exact matched on risk-associated patient characteristics and attending surgeon, overlapping surgery patients pre-ACS and post-ACS guideline revision experienced similar rates of 30-day and 90-day outcomes. CONCLUSIONS: After the ACS guideline revision, no discernable impact was observed on postoperative outcomes after lumbar fusion performed with overlap.

Causalgia: a military pain syndrome.

Causalgia, officially known as complex regional pain syndrome type II, is a pain syndrome characterized by severe burning pain, motor and sensory dysfunction, and changes in skin color and temperature sensation distal to an injured peripheral nerve. The pain syndrome primarily tends to affect combat soldiers after they sustain wartime injuries from blasts and gunshots. Here, the authors provide a historical narrative that showcases the critical contributions of military physicians to our understanding of causalgia and to the field of peripheral nerve neurosurgery as a whole.

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.

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.

Matched Analysis of the Risk Assessment and Prediction Tool for Discharge Planning Following Single-Level Posterior Lumbar Fusion.

OBJECTIVES: Predicting patient needs for extended care after spinal fusion remains challenging. The Risk Assessment and Prediction Tool (RAPT) was externally developed to predict discharge disposition after nonspine orthopedic surgery but remains scarcely used in neurosurgery. The present study is the first to use coarsened exact matching-which incorporated patient characteristics known to independently affect outcomes-for 1:1 matching across a large population of single-level, posterior lumbar fusions, to isolate the predictive value of preoperative RAPT score on postoperative discharge disposition. METHODS: Preoperative RAPT scores were prospectively calculated for 1066 patients undergoing consecutive single-level, posterior-only lumbar fusion within a single, university healthcare system. The primary outcome was discharge disposition. Logistic regression was executed across all patients, evaluating the RAPT score as a continuous variable to predict home discharge. Subsequently, patients were retrospectively clustered into predicted risk cohorts-validated within prior orthopedic joint research-based on the RAPT score (Lowest, Intermediate, and Highest Risk). Coarsened exact matching was performed among predicted risk cohorts, and outcomes were compared between exact-matched groups. RESULTS: Among all patients, single-point increases in the RAPT score (i.e., decrease in predicted risk) were associated a 75% increased odds of home discharge (P < 0.001). Exact-matched analysis demonstrated increased odds of home discharge by 400% when comparing the Lowest versus Highest Risk cohorts (P = 0.004), by 750% when comparing the Intermediate versus Highest Risk cohorts (P < 0.001), and by 200% when comparing the Lowest versus Intermediate Risk cohorts (P < 0.001). CONCLUSIONS: The RAPT score, captured in preoperative evaluations, can be highly predictive of discharge disposition following single-level, posterior lumbar fusion.

Endoscopic fenestration of a giant frontal arachnoid cyst: Operative technique and anatomical nuances.

Endoscopic fenestration is best as it is minimally invasive and does not require hardware in the surgical site (Figure 1). This case shows the safety of endoscopic fenestration and the utility of operative adjuncts (J Korean Med Sci. 1999;14:443; Neurosurg Focus. 2005;19:E7).

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.

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.

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.

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.

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.