Factors Associated With Extended Length of Stay and 90-Day Readmission Rates Following ACDF

The Association between Race and Extended Length of Stay in Low-energy Proximal Humerus Fractures in Elderly Patients

INTRODUCTION

Proximal humerus fractures (PHFs) are one of the most common fractures among patients aged 65 years and older, commonly due to low-energy mechanisms. It is essential to identify drivers of increased healthcare utilization in geriatric PHF patients and bring awareness to any disparities in care. Here, we identify factors associated with the likelihood of inpatient admission and prolonged hospital stay among patients aged 65 years and older who sustain PHF due to falls.

METHODS

A national database was used to identify patients aged 65 years and older who suffered proximal humeral fractures due to a fall. Patient factors were analyzed for association with the likelihood of admission and odds of prolonged stay (≥5 days).

RESULTS

In the study period, 75,385 PHF patients who met our inclusion criteria presented to the emergency department and 14,118 (18.7%) were admitted. Black race was significantly associated with decreased odds of admission ( P < 0.001) and increased likelihood of prolonged stay ( P = 0.007) compared with White patients. Patients aged 75 to 84 and 85+ were both more likely to be admitted ( P < 0.001) and experienced a prolonged hospital stay ( P = 0.015). Patients undergoing surgical intervention with reverse total shoulder arthroplasty were associated with admission and prolonged length of stay ( P < 0.001). Hospitals in Midwestern ( P < 0.001) and Western ( P < 0.001) regions exhibited lower rates of admission and Northeastern hospitals were associated with prolonged stays ( P = 0.001). Finally, trauma and nonmetropolitan ( P < 0.001) centers were associated with admission.

CONCLUSION

Our study highlights the notable influence of age and race on the likelihood of hospital admission and prolonged hospital stay. Specifically, Black patients exhibited prolonged hospital stay, which has been associated with lower-quality care, warranting additional exploration. Understanding these demographic and hospital-related factors is essential for optimizing resource allocation and reducing healthcare disparities in the care of PHF patients, especially as the population ages and the incidence of PHF continues to rise.

Clinicosocial determinants of hospital stay following cervical decompression: A public healthcare perspective and machine learning model

OBJECTIVE

Post-operative length of hospital stay (LOS) is a valuable measure for monitoring quality of care provision, patient recovery, and guiding hospital resource management. But the impact of patient ethnicity, socio-economic deprivation as measured by the indices of multiple deprivation (IMD), and pre-existing health conditions on LOS post-anterior cervical decompression and fusion (ACDF) is under-researched in public healthcare settings.

METHODS

From 2013 to 2023, a retrospective study at a single center reviewed all ACDF procedures. We analyzed 14 non-clinical predictors-including demographics, comorbidities, and socio-economic status-to forecast a categorized LOS: short (≤2 days), medium (2-3 days), or long (>3 days). Three machine learning (ML) models were developed and assessed for their prediction reliability.

RESULTS

2033 ACDF patients were analyzed; 79.44 % had a LOS ≤ 2 days. Significant predictors of LOS included patient sex (HR:0.81[0.74-0.88], p < 0.005), IMD decile (HR:1.38[1.24-1.53], p < 0.005), smoking (HR:1.24[1.12-1.38], p < 0.005), DM (HR:0.70[0.59-0.84], p < 0.005), and COPD (HR:0.66, p = 0.01). Asian patients had the highest mean LOS (p = 0.003). Testing on 407 patients, the XGBoost model achieved 80.95 % accuracy, 71.52 % sensitivity, 85.76 % specificity, 71.52 % positive predictive value, and a micro F1 score of 0.715. This model is available at: https://acdflos.streamlit.app.

CONCLUSIONS

Utilizing non-clinical pre-operative parameters such as patient ethnicity, socio-economic deprivation index, and baseline comorbidities, our ML model effectively predicts postoperative LOS for patient undergoing ACDF surgeries. Yet, as the healthcare landscape evolves, such tools will require further refinement to integrate peri and post-operative variables, ensuring a holistic decision support tool.

Late-week Multilevel Anterior Cervical Discectomy and Fusion Associated With Increased Length of Stay

STUDY DESIGN

Retrospective analysis of clinical data from a single institution.

OBJECTIVE

To assess the day of surgery during the week as a possible predictor of length of stay (LOS) following anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Surgeries later in the week may result in longer LOS and higher costs for joint arthroplasty, yet this is unclear following spine surgery. Procedures performed later in the week may lead to weekend admissions when there are limited services that may contribute to an extended LOS. We attempt to identify associations between day of surgery and LOS, readmission, and complications following single- and multilevel ACDF.

MATERIALS AND METHODS

Patients at a single institution undergoing ACDF by 7 primary surgeons in both orthopedic and neurosurgery spine departments between 2015 and 2019 were retrospectively reviewed. Patients were stratified by surgery day at either the beginning (Monday/Tuesday) or end (Thursday/Friday) of the week and by single- or multilevel ACDF. Surgery for trauma, infections, adjacent level disease, or revision were excluded. Patient demographics, Charlson Comorbidity Index (CCI), LOS, postoperative complications, and readmission rates were assessed.

RESULTS

Six hundred fifty-two patients underwent ACDF. For single-level ACDF, 222 were reviewed, with 112 having surgery at the beginning and 110 at the end of the week. For multilevel ACDF, 431 were reviewed, with 192 having surgery at the beginning and 239 at the end of the week. No differences in pre- or postoperative variables were determined for single-level ACDF. Despite no differences in pre-operative variables, CCI, operative duration, or number of levels, late-week multilevel ACDF had longer average LOS (2.8±3.0 days) compared to early-week surgery (2.0±2.0 days) ( P =0.018).

CONCLUSIONS

Late-week multilevel ACDF was associated with an increased LOS, as it may prove beneficial to surgical planning. This conflicts with previous reports that day of week was not associated with LOS following ACDF.

LEVEL OF EVIDENCE

III.

Social determinants of health and disparities in spine surgery: a 10-year analysis of 8,565 cases using ensemble machine learning and multilayer perceptron

BACKGROUND CONTEXT

The influence of SDOH on spine surgery is poorly understood. Historically, researchers commonly focused on the isolated influences of race, insurance status, or income on healthcare outcomes. However, analysis of SDOH is becoming increasingly more nuanced as viewing social factors in aggregate rather than individually may offer more precise estimates of the impact of SDOH on healthcare delivery.

PURPOSE

The aim of this study was to evaluate the effects of patient social history on length of stay (LOS) and readmission within 90 days following spine surgery using ensemble machine learning and multilayer perceptron.

STUDY DESIGN

Retrospective chart review.

PATIENT SAMPLE

8,565 elective and emergency spine surgery cases performed from 2013 to 2023 using our institution's database of longitudinally collected electronic medical record information.

OUTCOMES MEASURES

Patient LOS, discharge disposition, and rate of 90-day readmission.

METHODS

Ensemble machine learning and multilayer perceptron were employed to predict LOS and readmission within 90 days following spine surgery. All other subsequent statistical analysis was performed using SPSS version 28. To further assess correlations among variables, Pearson's correlation tests and multivariate linear regression models were constructed. Independent sample t-tests, paired sample t-tests, one-way analysis of variance (ANOVA) with post-hoc Bonferroni and Tukey corrections, and Pearson's chi-squared test were applied where appropriate for analysis of continuous and categorical variables.

RESULTS

Black patients demonstrated a greater LOS compared to white patients, but race and ethnicity were not significantly associated with 90-day readmission rates. Insured patients had a shorter LOS and lower readmission rates compared to non-insured patients, as did privately insured patients compared to publicly insured patients. Patients discharged home had lower LOS and lower readmission rates, compared to patients discharged to other facilities. Marriage decreased both LOS and readmission rates, underweight patients showcased increased LOS and readmission rates, and religion was shown to impact LOS and readmission rates. When utilizing patient social history, lab values, and medical history, machine learning determined the top 5 most-important variables for prediction of LOS -along with their respective feature importances-to be insurance status (0.166), religion (0.100), ICU status (0.093), antibiotic use (0.061), and case status: elective or urgent (0.055). The top 5 most-important variables for prediction of 90-day readmission-along with their respective feature importances-were insurance status (0.177), religion (0.123), discharge location (0.096), emergency case status (0.064), and history of diabetes (0.041).

CONCLUSIONS

This study highlights that SDOH is influential in determining patient length of stay, discharge disposition, and likelihood of readmission following spine surgery. Machine learning was utilized to accurately predict LOS and 90-day readmission with patient medical history, lab values, and social history, as well as social history alone.

Discharge within 1 day following elective single-level transforaminal lumbar interbody fusion: a propensityscore-matched analysis of predictors, complications, and readmission

STUDY DESIGN

This was a retrospective case-control study using 8 years of data from a nationwide database of surgical outcomes in the United States.

PURPOSE

This study aimed to improve our understanding of the risk factors associated with a length of stay (LOS) >1 day and aid in reducing postoperative hospitalization and complications.

OVERVIEW OF LITERATURE

Despite the proven safety of transforaminal lumbar interbody fusion (TLIF), some patients face prolonged postoperative hospitalization.

METHODS

Data were collected from the American College of Surgeons National Surgical Quality Improvement Program dataset from 2011 to 2018. The cohort was divided into patients with LOS up to 1 day (LOS ≤1 day), defined as same day or next-morning discharge, and patients with LOS >1 day (LOS >1 day). Univariable and multivariable regression analyses were performed to evaluate predictors of LOS >1 day. Propensity-score matching was performed to compare pre- and postdischarge complication rates.

RESULTS

A total of 12,664 eligible patients with TLIF were identified, of which 14.8% had LOS ≤1 day and 85.2% had LOS >1 day. LOS >1 day was positively associated with female sex, Hispanic ethnicity, diagnosis of spondylolisthesis, American Society of Anesthesiologists classification 3, and operation length of >150 minutes. Patients with LOS >1 day were more likely to undergo intraoperative/postoperative blood transfusion (0.3% vs. 4.5%, p<0.001) and reoperation (0.1% vs. 0.6%, p=0.004). No significant differences in the rates of postdischarge complications were found between the matched groups.

CONCLUSIONS

Patients with worsened preoperative status, preoperative diagnosis of spondylolisthesis, and prolonged operative time are more likely to require prolonged hospitalization and blood transfusions and undergo unplanned reoperation. To reduce the risk of prolonged hospitalization and associated complications, patients indicated for TLIF should be carefully selected.

Development and Validation of Machine Learning-Based Predictive Model for Prolonged Hospital Stay after Decompression Surgery for Lumbar Spinal Canal Stenosis

Introduction

Precise prediction of hospital stay duration is essential for maximizing resource utilization during surgery. Existing lumbar spinal stenosis (LSS) surgery prediction models lack accuracy and generalizability. Machine learning can improve accuracy by considering preoperative factors. This study aimed to develop and validate a machine learning-based model for estimating hospital stay duration following decompression surgery for LSS.

Methods

Data from 848 patients who underwent decompression surgery for LSS at three hospitals were examined. Twelve prediction models, using 79 preoperative variables, were developed for postoperative hospital stay estimation. The top five models were chosen. Fourteen models predicted prolonged hospital stay (≥14 days), and the most accurate model was chosen. Models were validated using a randomly divided training sample (70%) and testing cohort (30%).

Results

The top five models showed moderate linear correlations (0.576-0.624) between predicted and measured values in the testing sample. The ensemble of these models had moderate prediction accuracy for final length of stay (linear correlation 0.626, absolute mean error 2.26 days, standard deviation 3.45 days). The c5.0 decision tree model was the top predictor for prolonged hospital stay, with accuracies of 89.63% (training) and 87.2% (testing). Key predictors for longer stay included JOABPEQ social life domain, facility, history of vertebral fracture, diagnosis, and Visual Analogue Scale (VAS) of low back pain.

Conclusions

A machine learning-based model was developed to predict postoperative hospital stay after LSS decompression surgery, using data from multiple hospital settings. Numerical prediction of length of stay was not very accurate, although favorable prediction of prolonged stay was accomplished using preoperative factors. The JOABPEQ social life domain score was the most important predictor.

Safety and efficacy of day anterior cervical discectomy and fusion procedure for degenerative cervical spondylosis: a retrospective analysis

OBJECTIVE

Our study aimed to develop a day anterior cervical discectomy and fusion (ACDF) procedure to treat degenerative cervical spondylosis (DCS). The goal was to analyze its clinical implications, safety, and early effects to provide a better surgical option for eligible DCS patients.

METHODS

A retrospective analysis was performed to identify DCS patients who underwent day ACDF from September 2022 to August 2023. The operative time, intraoperative blood loss, postoperative drainage, preoperative and postoperative visual analog scale (VAS) scores, neck disability index (NDI) scores, Japanese Orthopedic Association (JOA) scores, JOA recovery rate (RR), incidence of dysphagia-related symptoms, 30-day hospital readmission rate, and incidence of other complications were recorded to evaluate early clinical outcomes. Radiography was performed to assess the location of the implants, neurological decompression, and cervical physiological curvature.

RESULTS

All 33 patients (23 women and 10 men) underwent successful surgery and experienced significant symptomatic and neurological improvements. Among them, 26 patients underwent one-segment ACDF, 5 underwent two-segment ACDF, and 2 underwent three-segment ACDF. The average operative time was 71.1 ± 20.2 min, intraoperative blood loss was 19.1 ± 6.2 mL, and postoperative drainage was 9.6 ± 5.8 mL. The preoperative VAS and NDI scores improved postoperatively (7.1 ± 1.2 vs. 3.1 ± 1.3 and 66.7% ± 4.8% vs. 24.1% ± 2.5%, respectively), with a significant difference (P < 0.01). Moreover, the preoperative JOA scores improved significantly postoperatively (7.7 ± 1.3 vs. 14.2 ± 1.4; P < 0.01) with an RR of 93.9% in good or excellent. Postoperative dysphagia-related symptoms occurred in one patient (3.0%). During the follow-up period, no patient was readmitted within 30 days after discharge; however, an incisional hematoma was reported in one patient on the 6th day after discharge, which was cured by pressure dressing. The postoperative radiographs revealed perfect implant positions and sufficient nerve decompression in all patients. Furthermore, the preoperative cervical physiological curvature improved significantly after the operation (14.5° ± 4.0° vs. 26.3° ± 5.4°; P < 0.01).

CONCLUSIONS

Day ACDF has good safety and early clinical efficacy, and it could be an appropriate choice for eligible DCS patients.

Disparities in postoperative complications and perioperative events based on insurance status following elective spine surgery: A systematic review and meta-analysis

Background

Increasing evidence demonstrates disparities among patients with differing insurance statuses in the field of spine surgery. However, no pooled analyses have performed a robust review characterizing differences in postoperative outcomes among patients with varying insurance types.

Methods

A comprehensive literature search of the PUBMED, MEDLINE(R), ERIC, and EMBASE was performed for studies comparing postoperative outcomes in patients with private insurance versus government insurance. Pooled incidence rates and odds ratios were calculated for each outcome and meta-analyses were conducted for 3 perioperative events and 2 types of complications. In addition to pooled analysis, sub-analyses were performed for each outcome in specific government payer statuses.

Results

Thirty-eight studies (5,018,165 total patients) were included. Compared with patients with private insurance, patients with government insurance experienced greater risk of 90-day re-admission (OR 1.84, p<.0001), non-routine discharge (OR 4.40, p<.0001), extended LOS (OR 1.82, p<.0001), any postoperative complication (OR 1.61, p<.0001), and any medical complication (OR 1.93, p<.0001). These differences persisted across outcomes in sub-analyses comparing Medicare or Medicaid to private insurance. Similarly, across all examined outcomes, Medicare patients had a higher risk of experiencing an adverse event compared with non-Medicare patients. Compared with Medicaid patients, Medicare patients were only more likely to experience non-routine discharge (OR 2.68, p=.0007).

Conclusions

Patients with government insurance experience greater likelihood of morbidity across several perioperative outcomes. Additionally, Medicare patients fare worse than non-Medicare patients across outcomes, potentially due to age-based discrimination. Based on these results, it is clear that directed measures should be taken to ensure that underinsured patients receive equal access to resources and quality care.

Association Between Age-stratified Cohorts and Perioperative Complications and 30-day and 90-day Readmission in Patients Undergoing Single-level Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To assess perioperative complication rates and readmission rates after ACDF in a patient population of advanced age.

SUMMARY OF BACKGROUND DATA

Readmission rates after ACDF are important markers of surgical quality and, with recent shifts in reimbursement schedules, they are rapidly gaining weight in the determination of surgeon and hospital reimbursement.

METHODS

Patients 18 years of age and older who underwent elective single-level ACDF were identified in the National Readmissions Database (NRD) and stratified into 4 cohorts: 18-39 ("young"), 40-64 ("middle"), 65-74 ("senior"), and 75+ ("elderly") years of age. For each cohort, the perioperative complications, frequency of those complications, and number of patients with at least 1 readmission within 30 and 90 days of discharge were analyzed. χ 2 tests were used to calculate likelihood of complications and readmissions.

RESULTS

There were 1174 "elderly" patients in 2016, 1072 in 2017, and 1010 in 2018 who underwent ACDF. Their rate of any complication was 8.95%, 11.00%, and 13.47%, respectively ( P <0.0001), with dysphagia and acute posthemorrhagic anemia being the most common across all 3 years. They experienced complications at a greater frequency than their younger counterparts (15.80%, P <0.0001; 16.98%, P <0.0001; 21.68%, P <0.0001). They also required 30-day and 90-day readmission more frequently ( P <0.0001).

CONCLUSION

It has been well-established that advanced patient age brings greater risk of perioperative complications in ACDF surgery. What remains unsettled is the characterization of this age-complication relationship within specific age cohorts and how these complications inform patient hospital course. Our study provides an updated analysis of age-specific complications and readmission rates in ACDF patients. Orthopedic surgeons may account for the rise in complication and readmission rates in this population with the corresponding reduction in length and stay and consider this relationship before discharging elderly ACDF patients.

Indication as a predictor for outcomes in anterior cervical discectomy and fusion: The impact of myelopathy on disposition

BACKGROUND

While the indication for Anterior Cervical Discectomy and Fusion (ACDF) may influence the expected postoperative course, there is limited data comparing how length of stay (LOS) and disposition for patients with myelopathy differ from those with radiculopathy. This study aimed to compare LOS and discharge disposition, in patients undergoing ACDF for cervical radiculopathy versus those for myelopathy.

METHODS

A retrospective review of all adult ACDF cases between 2013 and 2019 was conducted analyzing sex, age, race, comorbidities, level of surgery, myelopathy measures when applicable, complications, dysphagia, hospital LOS, and discharge disposition.

RESULTS

A total of 157 patients were included in the study with 73 patients undergoing an ACDF for radiculopathy and 84 for myelopathy. Univariate analysis determined older age (p < 0.01), male sex (p = 0.03), presence of CKD (p < 0.01) or COPD (p = 0.01), surgery at C3/4 level (p = 0.01), and indication (p < 0.01) as predictors for a discharge to either acute rehabilitation or a skilled nursing facility rather than to home. Multivariate logistic regression demonstrated age and indication as the only independent predictors of disposition, with home disposition being more likely with decreased age (OR 0.92, 95 % CI 0.86-0.98) and radiculopathy as the diagnosis (OR 6.72, 95 % CI 1.22- 37.02).

CONCLUSIONS

Myelopathic patients, as compared to those with radiculopathy at presentation, had significantly longer LOS, increased dysphagia, and were more often discharged to a facility. Understanding these two distinct populations as separate entities will streamline the pre and post-surgical care as the current DRG codes and ICD 10 PCS do not differentiate the expected post-operative course in patients undergoing ACDF for myelopathy versus radiculopathy.

Public health insurance, frailty, and lack of home support predict rehab discharge following elective anterior cervical discectomy and fusion

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) is a commonly-performed and generally well-tolerated procedure used to treat cervical disc herniation. Rarely, patients require discharge to inpatient rehab, leading to inconvenience for the patient and increased healthcare expenditure for the medical system.

PURPOSE

The objective of this study was to create an accurate and practical predictive model for, as well as delineate associated factors with, rehab discharge following elective ACDF.

STUDY DESIGN

This was a retrospective, single-center, cohort study.

PATIENT SAMPLE

Patients who underwent ACDF between 2012 and 2022 were included. Those with confounding diagnoses or who underwent concurrent, staged, or nonelective procedures were excluded.

OUTCOME MEASURES

Primary outcomes for this study included measurements of accuracy for predicting rehab discharge. Secondary outcomes included associations of variables with rehab discharge.

METHODS

Current Procedural Terminology codes identified patients. Charts were reviewed to obtain additional demographic and clinical characteristics on which an initial univariate analysis was performed. Two logistic regression and two machine learning models were trained and evaluated on the data using cross-validation. A multimodel logistic regression was implemented to analyze independent variable associations with rehab discharge.

RESULTS

A total of 466 patients were included in the study. The logistic regression model with minimum corrected Akaike information criterion score performed best overall, with the highest values for area under the receiver operating characteristic curve (0.83), Youden's J statistic (0.71), balanced accuracy (85.7%), sensitivity (90.3%), and positive predictive value (38.5%). Rehab discharge was associated with a modified frailty index of 2 (p=.007), lack of home support (p=.002), and having Medicare or Medicaid insurance (p=.007) after correction for multiple hypotheses.

CONCLUSIONS

Nonmedical social determinants of health, such as having public insurance or a lack of support at home, may play a role in rehab discharge following elective ACDF. In combination with the modified frailty index and other variables, these factors can be used to predict rehab discharge with high accuracy, improving the patient experience and reducing healthcare costs.

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.

An 11-Year-Long Analysis of the Risks Associated With Age in Patients Undergoing Anterior Cervical Discectomy and Fusion in a Large, Urban Academic Hospital

STUDY DESIGN

A retrospective database study of patients at an urban academic medical center undergoing an Anterior Cervical Discectomy and Fusion (ACDF) surgery between 2008 and 2019.

OBJECTIVE

ACDF is one of the most common spinal procedures. Old age has been found to be a common risk factor for postoperative complications across a plethora of spine procedures. Little is known about how this risk changes among elderly cohorts such as the difference between elderly (60+) and octogenarian (80+) patients. This study seeks to analyze the disparate rates of complications following elective ACDF between patients aged 60-69 or 70-79 and 80+ at an urban academic medical center.

METHODS

We identified patients who had undergone ACDF procedures using CPT codes 22,551, 22,552, and 22,554. Emergent procedures were excluded, and patients were subdivided on the basis of age. Then each cohort was propensity matched for univariate and univariate logistic regression analysis.

RESULTS

The propensity matching resulted in 25 pairs in both the 70-79 and 80+ y.o. cohort comparison and 60-69 and 80+ y.o. cohort comparison. None of the cohorts differed significantly in demographic variables. Differences between elderly cohorts were less pronounced: the 80+ y.o. cohort experienced only significantly higher total direct cost (P = .03) compared to the 70-79 y.o. cohort and significantly longer operative time (P = .04) compared to the 60-69 y.o. cohort.

CONCLUSIONS

Octogenarian patients do not face much riskier outcomes following elective ACDF procedures than do younger elderly patients. Age alone should not be used to screen patients for ACDF.

Preoperative predictors of prolonged hospitalization in patients undergoing lateral lumbar interbody fusion

PURPOSE

We aim to examine the preoperative factors associated with increased postoperative length of stay in patients undergoing LLIF in the hospital setting.

METHODS

Patient demographics, perioperative characteristics, and patient-reported outcome measures (PROMs) were collected from a single-surgeon database. Patients undergoing LLIF in the hospital setting were separated into postoperative LOS <48 h (H) and LOS ≥ 48H. Univariate analysis for preoperative characteristics was utilized to determine covariates for multivariable logistic regression. Multivariable logistic regression was then utilized to determine significant predictors of extended postoperative length of stay. Secondary univariate analysis of inpatient complications, operative, and postoperative characteristics were calculated to determine postoperative factors associated with prolonged hospitalization.

RESULTS

Two-hundred and forty patients were identified with 115 patients' LOS ≥ 48H. Univariate analysis identified age/Charlson Comorbidity Index (CCI) score/gender/insurance type/number of contiguous fused levels/preoperative PROMs of Visual Analog Scale (VAS) back/VAS leg/Patient-Reported Outcomes Measurement Information System (PROMIS-PF)/Oswestry Disability Index (ODI)/degenerative spondylolisthesis diagnoses/foraminal stenosis/central stenosis for multivariable logistic regression. Multivariable logistic regression calculated significant positive predictors of LOS ≥ 48H to be age/3-level fusion/preoperative ODI scores. Negative predictors of LOS ≥ 48H were the diagnosis of foraminal stenosis/preoperative PROMIS-PF/male gender. The secondary analysis determined that patients with longer operative time/estimated blood loss/transfusion/postoperative day 0 and 1 pain and narcotic consumption/complications of altered mental status/postoperative anemia/fever/ileus/urinary retention were associated with prolonged hospitalization.

CONCLUSION

Older patients undergoing LLIF with greater preoperative disability and 3-level fusion were more likely to require prolonged hospitalization. Male patients with higher preoperative physical function and who were diagnosed with foraminal stenosis were less likely to require prolonged hospitalization.

Comparison of Perioperative Complications After Anterior-Posterior Versus Posterior-Anterior-Posterior Cervical Fusion: A Retrospective Review of 153 Consecutive Cases

BACKGROUND

Although published data support the utilization of circumferential fusion to treat select cervical spine pathologies, it is unclear whether the posterior-anterior-posterior (PAP) fusion has increased risks compared with the anterior-posterior fusion.

OBJECTIVE

To evaluate the differences in perioperative complications between the 2 circumferential cervical fusion approaches.

METHODS

One hundred fifty-three consecutive adult patients who underwent single-staged circumferential cervical fusion for degenerative pathologies from 2010 to 2021 were retrospectively reviewed. Patients were stratified into the anterior-posterior ( n = 116) and PAP ( n = 37) groups. The primary outcomes assessed were major complications, reoperation, and readmission.

RESULTS

Although the PAP group was older ( P = .024), predominantly female ( P = .024), with higher baseline neck disability index ( P = .026), cervical sagittal vertical axis ( P = .001), and previous cervical operation rate ( P < .00001), the major complication, reoperation, and readmission rates were not significantly different from the 360° group. Although the PAP group had higher urinary tract infection ( P = .043) and transfusion ( P = .007) rates, higher estimated blood loss ( P = .034), and longer operative times ( P < .00001), these differences were insignificant after the multivariable analysis. Overall, operative time was associated with older age (odds ratio [OR] 17.72, P = .042), atrial fibrillation (OR 158.30, P = .045), previous cervical operation (OR 5.05, P = .051), and lower baseline C1 - 7 lordosis (OR 0.93, P = .007). Higher estimated blood loss was associated with older age (OR 1.13, P = .005), male gender (OR 323.31, P = .047), and higher baseline cervical sagittal vertical axis (OR 9.65, P = .022).

CONCLUSION

Despite some differences in preoperative and intraoperative variables, this study suggests both circumferential approaches have comparable reoperation, readmission, and complication profiles, all of which are high.

Innovative design of minimal invasive biodegradable poly(glycerol-dodecanoate) nucleus pulposus scaffold with function regeneration

Minimally invasive biodegradable implants with regeneration have been a frontier trend in clinic. Degeneration of nucleus pulposus (NP) is irreversible in most of spine diseases, and traditional spinal fusion or discectomy usually injure adjacent segments. Here, an innovative minimally invasive biodegradable NP scaffold with function regeneration inspired by cucumber tendril is developed using shape memory polymer poly(glycerol-dodecanoate) (PGD), whose mechanical property is controlled to the similar with human NP by adjusting synthetic parameters. The chemokine stromal cell-derived factor-1α (SDF-1α) is immobilized to the scaffold recruiting autologous stem cells from peripheral tissue, which has better ability of maintaining disc height, recruiting autologous stem cells, and inducing regeneration of NP in vivo compared to PGD without chemokine group and hydrogel groups significantly. It provides an innovative way to design minimally invasive implants with biodegradation and functional recovery, especially for irreversible tissue injury, including NP, cartilage and so on.

Neurosurgeons Deliver Similar Quality Care Regardless of First Assistant Type: Resident Physician versus Nonphysician 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 vs. nonphysician surgical assistant [NPSA]), among otherwise exact-matched patients.

METHODS

The authors retrospectively analyzed 3395 adult patients undergoing single-level, posterior-only lumbar fusion at a single academic medical center. Primary outcomes included readmissions, emergency department 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, emergency department visits, reoperation, or mortality) within 30 days or 90 days of the index operation between patients who had resident physicians and those who had 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.

Clinical Outcomes and Cost Differences Between Patients Undergoing Primary Anterior Cervical Discectomy and Fusion Procedures with Private or Medicare Insurance: A Propensity Score-Matched Study

OBJECTIVE

We assessed whether the insurance type reflects a patient's quality of care after an anterior discectomy and fusion (ACDF) procedure by comparing differences in the postoperative complications, readmission rates, reoperation rates, lengths of hospital stay, and cost of treatment between patients with Medicare versus private insurance.

METHODS

Propensity score matching was used to match patient cohorts insured by Medicare and private insurance in the MarketScan Commercial Claims and Encounters Database (2007-2016). Age, sex, year of operation, geographic region, comorbidities, and operative factors were used to match cohorts of patients who had undergone an ACDF procedure.

RESULTS

A total of 110,911 patients met the inclusion criteria. Of these patients, 97,543 patients (87.9%) were privately insured and 13,368 patients (12.1%) were insured by Medicare. The propensity score matching algorithm matched 7026 privately insured patients to 7026 Medicare patients. After matching, no significant differences were found in the 90-day postoperative complication rates, lengths of stay, or reoperation rates between the Medicare and privately insured cohorts. The Medicare group had had lower postoperative readmission rates for all time points: 30 days (1.8% vs. 4.6%; P < 0.001), 60 days (2.5% vs. 6.3%; P < 0.001), and 90 days (4.2% vs. 7.7%; P < 0.001). The median payment to physicians was significantly lower for the Medicare group ($3885 vs. $5601; P < 0.001).

CONCLUSIONS

In the present study, propensity score matched patients covered by Medicare and private insurance who had undergone an ACDF procedure had had similar treatment outcomes.

Using Machine Learning and Deep Learning Algorithms to Predict Postoperative Outcomes Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A retrospective cohort study from a multisite academic medical center.

OBJECTIVE

To construct, evaluate, and interpret a series of machine learning models to predict outcomes related to inpatient health care resource utilization for patients undergoing anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Reducing postoperative health care utilization is an important goal for improving the delivery of surgical care and serves as a metric for quality assessment. Recent data has shown marked hospital resource utilization after ACDF surgery, including readmissions, and ED visits. The burden of postoperative health care use presents a potential application of machine learning techniques, which may be capable of accurately identifying at-risk patients using patient-specific predictors.

METHODS

Patients 18-88 years old who underwent ACDF from 2011 to 2021 at a multisite academic center and had preoperative lab values within 3 months of surgery were included. Outcomes analyzed included 90-day readmissions, postoperative length of stay, and nonhome discharge. Four machine learning models-Extreme Gradient Boosted Trees, Balanced Random Forest, Elastic-Net Penalized Logistic Regression, and a Neural Network-were trained and evaluated through the Area Under the Curve estimates. Feature importance scores were computed for the highest-performing model per outcome through model-specific metrics.

RESULTS

A total of 1026 cases were included in the analysis cohort. All machine learning models were predictive for outcomes of interest, with the Random Forest algorithm consistently demonstrating the strongest average area under the curve performance, with a peak performance of 0.84 for nonhome discharge. Important features varied per outcome, though age, body mass index, American Society of Anesthesiologists classification >2, and medical comorbidities were highly weighted in the studied outcomes.

CONCLUSIONS

Machine learning models were successfully applied and predictive of postoperative health utilization after ACDF. Deployment of these tools can assist clinicians in determining high-risk patients.

LEVEL OF EVIDENCE

III.

Disparities in Elective Spine Surgery for Medicaid Beneficiaries: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

We sought to synthesize the literature investigating the disparities that Medicaid patients sustain with regards to 2 types of elective spine surgery, lumbar fusion (LF) and anterior cervical discectomy and fusion (ACDF).

METHODS

Our review was constructed in accordance with Preferred Reporting Items and Meta-analyses (PRISMA) guidelines and protocol. We systematically searched PubMed, Embase, Scopus, CINAHL, and Web of Science databases. We included studies comparing Medicaid beneficiaries to other payer categories with regards to rates of LF and ACDF, costs/reimbursement, and health outcomes.

RESULTS

A total of 573 articles were assessed. Twenty-five articles were included in the analysis. We found that the literature is consistent with regards to Medicaid disparities. Medicaid was strongly associated with decreased access to LF and ACDF, lower reimbursement rates, and worse health outcomes (such as higher rates of readmission and emergency department utilization) compared to other insurance categories.

CONCLUSIONS

In adult patients undergoing elective spine surgery, Medicaid insurance is associated with wide disparities with regards to access to care and health outcomes. Efforts should focus on identifying causes and interventions for such disparities in this vulnerable population.

Robust prediction of nonhome discharge following elective anterior cervical discectomy and fusion using explainable machine learning

PURPOSE

Predict nonhome discharge (NHD) following elective anterior cervical discectomy and fusion (ACDF) using an explainable machine learning model.

METHODS

2227 patients undergoing elective ACDF from 2008 to 2019 were identified from a single institutional database. A machine learning model was trained on preoperative variables, including demographics, comorbidity indices, and levels fused. The validation technique was repeated stratified K-Fold cross validation with the area under the receiver operating curve (AUROC) statistic as the performance metric. Shapley Additive Explanation (SHAP) values were calculated to provide further explainability regarding the model's decision making.

RESULTS

The preoperative model performed with an AUROC of 0.83 ± 0.05. SHAP scores revealed the most pertinent risk factors to be age, medicare insurance, and American Society of Anesthesiology (ASA) score. Interaction analysis demonstrated that female patients over 65 with greater fusion levels were more likely to undergo NHD. Likewise, ASA demonstrated positive interaction effects with female sex, levels fused and BMI.

CONCLUSION

We validated an explainable machine learning model for the prediction of NHD using common preoperative variables. Adding transparency is a key step towards clinical application because it demonstrates that our model's "thinking" aligns with clinical reasoning. Interactive analysis demonstrated that those of age over 65, female sex, higher ASA score, and greater fusion levels were more predisposed to NHD. Age and ASA score were similar in their predictive ability. Machine learning may be used to predict NHD, and can assist surgeons with patient counseling or early discharge planning.

Patients with radiculopathy have worse baseline disability and greater improvements following anterior cervical discectomy and fusion compared to patients with myelopathy

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) is commonly performed in patients with radiculopathy and myelopathy. Although the goal of surgery in patients with radiculopathy is to improve function and reduce pain, patients with myelopathy undergo surgery to halt disease progression. Although the expectations between these preoperative diagnoses are generally understood to be disparate by spine surgeons, there is limited literature demonstrating their discordant outcomes.

PURPOSE

To compare improvements in patient reported outcome measures (PROMs) for patients undergoing ACDF for myelopathy or radiculopathy. Secondarily, we analyzed the proportion of patients who attain the minimum clinically important difference (MCID) postoperatively using thresholds derived from radiculopathy, myelopathy, and mixed cohort studies.

STUDY DESIGN/SETTING

Single institution retrospective cohort study PATIENT SAMPLE: Patients undergoing primary, elective ACDF with a preoperative diagnosis of radiculopathy or myelopathy and a complete set of preoperative and one-year postoperative PROMs.

OUTCOME MEASURES

Outcome measures included the following PROMs: Short-Form 12 Physical Component (PCS-12) and Mental Component (MCS-12) scores, the Visual Analog Scale (VAS) Arm score, and the Neck Disability Index (NDI). Hospital readmissions and revision surgery were also collected and evaluated.

METHODS

Patients undergoing an ACDF from 2014 to 2020 were identified and grouped based on preoperative diagnosis (radiculopathy or myelopathy). We utilized "general MCID" thresholds from a cohort of patients with degenerative spine conditions, and "specific MCID" thresholds generated from cohorts of patients with myelopathy or radiculopathy, respectively. Multivariate linear regressions were performed for delta (∆) PROMs and multivariate logistic regressions were performed for both general and specific MCID improvements.

RESULTS

A total of 798 patients met inclusion criteria. Patients with myelopathy had better baseline function and arm pain (MCS-12: 49.6 vs 47.6, p=.018; VAS Arm: 3.94 vs 6.02, p<.001; and NDI: 34.1 vs 41.9, p<.001), were older (p<.001), had more comorbidities (p=.014), more levels fused (p<.001), and had decreased improvement in PROMs following surgery compared to patients with radiculopathy (∆PCS-12: 4.76 vs 7.21, p=.006; ∆VAS Arm: -1.69 vs -3.70, p<.001; and ∆NDI: -11.94 vs -18.61, p<.001). On multivariate analysis, radiculopathy was an independent predictor of increased improvement in PCS-12 (β=2.10, p=.019), ∆NDI (β=-5.36, p<.001), and ∆VAS Arm (β=-1.93, p<.001). Radiculopathy patients were more likely to achieve general MCID improvements following surgery (NDI: Odds ratio (OR): 1.42, p=.035 and VAS Arm: OR: 2.98, p<.001), but there was no difference between patients with radiculopathy or myelopathy when using radiculopathy and myelopathy specific MCID thresholds (MCS-12: p=.113, PCS-12: p=.675, NDI: p=.108, and VAS Arm: p=.314).

CONCLUSIONS

Patients undergoing ACDF with myelopathy or radiculopathy represent two distinct patient populations with differing treatment indications and clinical outcomes. Compared to radiculopathy, patients with myelopathy have better baseline function, decreased improvement in PROMs, and are less likely to reach MCID using general threshold values, but there is no difference in the proportion reaching MCID when using specific threshold values.

LEVEL OF EVIDENCE

IRB.

Preadmission assessment of extended length of hospital stay with RFECV-ETC and hospital-specific data

Background

Patients who exceed their expected length of stay in the hospital come at a cost to stakeholders in the healthcare sector as bed spaces are limited for new patients, nosocomial infections increase and the outcome for many patients is hampered due to multimorbidity after hospitalization.

Objectives

This paper develops a technique for predicting Extended Length of Hospital Stay (ELOHS) at preadmission and their risk factors using hospital data.

Methods

A total of 91,468 records of patient’s hospital information from a private acute teaching hospital were used for developing a machine learning algorithm relaying on Recursive Feature Elimination with Cross-Validation and Extra Tree Classifier (RFECV-ETC). The study implemented Synthetic Minority Oversampling Technique (SMOTE) and tenfold cross-validation to determine the optimal features for predicting ELOHS while relying on multivariate Logistic Regression (LR) for computing the risk factors and the Relative Risk (RR) of ELOHS at a 95% confidence level.

Results

An estimated 11.54% of the patients have ELOHS, which increases with patient age as patients < 18 years, 18–40 years, 40–65 years and ≥ 65 years, respectively, have 2.57%, 4.33%, 8.1%, and 15.18% ELOHS rates. The RFECV-ETC algorithm predicted preadmission ELOHS to an accuracy of 89.3%. Age is a predominant risk factors of ELOHS with patients who are > 90 years—PAG (> 90) {RR: 1.85 (1.34–2.56), P:  < 0.001} having 6.23% and 23.3%, respectively, higher likelihood of ELOHS than patient 80–90 years old—PAG (80–90) {RR: 1.74 (1.34–2.38), P:  < 0.001} and those 70–80 years old—PAG (70–80) {RR: 1.5 (1.1–2.05), P: 0.011}. Those from admission category—ADC (US1) {RR: 3.64 (3.09–4.28, P:  < 0.001} are 14.8% and 70.5%, respectively, more prone to ELOHS compared to ADC (UC1) {RR: 3.17 (2.82–3.55), P:  < 0.001} and ADC (EMG) {RR: 2.11 (1.93–2.31), P:  < 0.001}. Patients from SES (low) {RR: 1.45 (1.24–1.71), P:  < 0.001)} are 13.3% and 45% more susceptible to those from SES (middle) and SES (high). Admission type (ADT) such as AS2, M2, NEWS, S2 and others {RR: 1.37–2.77 (1.25–6.19), P:  < 0.001} also have a high likelihood of contributing to ELOHS while the distance to hospital (DTH) {RR: 0.64–0.75 (0.56–0.82), P:  < 0.001}, Charlson Score (CCI) {RR: 0.31–0.68 (0.22–0.99), P:  < 0.001–0.043} and some VMO specialties {RR: 0.08–0.69 (0.03–0.98), P:  < 0.001–0.035} have limited influence on ELOHS.

Conclusions

Relying on the preadmission assessment of ELOHS helps identify those patients who are susceptible to exceeding their expected length of stay on admission, thus, making it possible to improve patients’ management and outcomes.

Prediction of Admission Costs Following Anterior Cervical Discectomy and Fusion Utilizing Machine Learning

STUDY DESIGN

Retrospective case series.

OBJECTIVE

Predict cost following anterior cervical discectomy and fusion (ACDF) within the 90-day global period using machine learning models.

BACKGROUND

The incidence of ACDF has been increasing with a disproportionate decrease in reimbursement. As bundled payment models become common, it is imperative to identify factors that impact the cost of care.

MATERIALS AND METHODS

The Nationwide Readmissions Database (NRD) was accessed in 2018 for all primary ACDFs by the International Classification of Diseases 10th Revision (ICD-10) procedure codes. Costs were calculated by utilizing the total hospital charge and each hospital's cost-to-charge ratio. Hospital characteristics, such as volume of procedures performed and wage index, were also queried. Readmissions within 90 days were identified, and cost of readmissions was added to the total admission cost to represent the 90-day healthcare cost. Machine learning algorithms were used to predict patients with 90-day admission costs >1 SD from the mean.

RESULTS

There were 42,485 procedures included in this investigation with an average age of 57.7±12.3 years with 50.6% males. The average cost of the operative admission was $24,874±25,610, the average cost of readmission was $25,371±11,476, and the average total cost was $26,977±28,947 including readmissions costs. There were 10,624 patients who were categorized as high cost. Wage index, hospital volume, age, and diagnosis-related group severity were most correlated with the total cost of care. Gradient boosting trees algorithm was most predictive of the total cost of care (area under the curve=0.86).

CONCLUSIONS

Bundled payment models utilize wage index and diagnosis-related groups to determine reimbursement of ACDF. However, machine learning algorithms identified additional variables, such as hospital volume, readmission, and patient age, that are also important for determining the cost of care. Machine learning can improve cost-effectiveness and reduce the financial burden placed upon physicians and hospitals by implementing patient-specific reimbursement.

Marijuana Use and its Effect on Clinical Outcomes and Revision Rates in Patients Undergoing Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

To determine if (1) preoperative marijuana use increased complications, readmission, or reoperation rates following anterior cervical discectomy and fusion (ACDF), (2) identify if preoperative marijuana use resulted in worse patient-reported outcome measures (PROMs), and (3) investigate if preoperative marijuana use affects the quantity of opioid prescriptions in the perioperative period.

SUMMARY OF BACKGROUND DATA

A growing number of states have legalized recreational and/or medical marijuana, thus increasing the number of patients who report preoperative marijuana use. The effects of marijuana on clinical outcomes and PROMs in the postoperative period are unknown.

METHODS

All patients 18 years of age and older who underwent primary one- to four-level ACDF with preoperative marijuana use at our academic institution were retrospectively identified. A 3:1 propensity match was conducted to compare patients who used marijuana versus those who did not. Patient demographics, surgical characteristics, clinical outcomes, and PROMs were compared between groups. Multivariate regression models measured the effect of marijuana use on the likelihood of requiring a reoperation and whether marijuana use predicted inferior PROM improvements at the one-year postoperative period.

RESULTS

Of the 240 patients included, 60 (25.0%) used marijuana preoperatively. Multivariate logistic regression analysis identified marijuana use (odds ratio=5.62, P <0.001) as a predictor of a cervical spine reoperation after ACDF. Patients who used marijuana preoperatively had worse one-year postoperative Physical Component Scores of the Short-Form 12 (PCS-12) ( P =0.001), Neck Disability Index ( P =0.003), Visual Analogue Scale (VAS) Arm ( P =0.044) and VAS Neck ( P =0.012). Multivariate linear regression found preoperative marijuana use did not independently predict improvement in PCS-12 (β=-4.62, P =0.096), Neck Disability Index (β=9.51, P =0.062), Mental Component Scores of the Short-Form 12 (MCS-12) (β=-1.16, P =0.694), VAS Arm (β=0.06, P =0.944), or VAS Neck (β=-0.44, P =0.617).

CONCLUSION

Preoperative marijuana use increased the risk of a cervical spine reoperation after ACDF, but it did not significantly change the amount of postoperative opioids used or the magnitude of improvement in PROMs.

LEVEL OF EVIDENCE

Levwl III.

Risk factors for ninety-day readmission following cervical surgery: a meta-analysis

Background

As an important evaluation index after cervical surgery, ninety-day readmission is gradually being valued. Our study collected the latest published relevant studies, analyzed the risk factors of ninety-day readmission after cervical surgery, and continuously improved the postoperative rehabilitation plan. This study focuses on two research hotspots: (1) What is the rate of ninety-day readmission after cervical surgery? (2) What are the risk factors affecting the ninety-day readmission?

Methods

Based on the Cochrane Library, PubMed, Web of Science, and Embase databases, this study searched for studies about ninety-day readmission after cervical surgery, from the establishment of the database to August 1, 2022. The evaluation indicators are as follows: age, American Society of Anesthesiology physical status (ASA) class, diabetes, hypertension, chronic heart diseases, chronic lung diseases, income, and payments for hospitalization. The meta-analysis was performed using Review Manager 5.4.

Results

Seven studies with 222,490 participants were eligible for our meta-analysis. The analysis displayed that there were statistically significant differences in the age (MD = − 4.60, 95%CI − 4.89–4.31, p < 0.001), diabetes (OR = 0.60, 95%CI 0.56–0.64, p < 0.00001), hypertension (OR = 0.40, 95%CI 0.30–0.54, p < 0.00001), chronic heart diseases (OR = 0.05, 95%CI 0.01–0.19, p < 0.00001), chronic lung diseases (OR = 0.46, 95%CI 0.43–0.49, p < 0.00001), income (OR = 2.85, 95%CI 1.82–4.46, p < 0.00001), and payments for hospitalization (OR = 2.29, 95%CI 1.14–4.59, p = 0.02) between readmission and no readmission groups. In terms of the ASA, there was no difference on the ninety-day readmission (p = 0.78).

Conclusion

Age, diabetes, hypertension, chronic heart diseases, chronic lung diseases, income, and payments for hospitalization are the risk factors of ninety‐day readmission following cervical surgery.

Emergency Department Visits Within 90 Days of Total Ankle Replacement

Background

Total ankle replacement (TAR) utilization in the United States has steeply increased in recent decades. Emergency department (ED) visits following TAR impacts patient satisfaction and health care costs and warrant exploration.

Methods

This retrospective cohort study utilized the 2010 to 2019 M91Ortho PearlDiver data set to identify TAR patients with at least 90 days of follow-up. PearlDiver contains billing claims data across all sites of care throughout the United States for all indications for care. Patient factors extracted included age, sex, Elixhauser Comorbidity Index (ECI), region of the country in which surgery was performed, insurance plan, and postoperative hospital length of stay. Ninety-day postoperative ED visit incidence, timing, frequency, and primary diagnoses were identified and compared to 1-year postoperative ED visit baseline data. Univariate and multivariate logistic regression analyses were used to determine risk factors for ED visits.

Results

Of 5930 TAR patients identified, ED visits within 90 days were noted for 497 (8.4%) patients. Of all ED visits, 32.0% occurred within 2 weeks following surgery. Multivariate analysis revealed several predictors of ED utilization: younger age (odds ratio [OR] 1.35 per decade decrease), female sex (OR 1.20), higher ECI (OR 1.32 per 2-point increase), TAR performed in the western US (OR 1.34), and Medicaid coverage (OR 2.70; 1.71-4.22 relative to Medicare) (P < .05 each). Surgical site issues comprised 78.0% of ED visits, with surgical site pain (57.0%) as the most common problem.

Conclusion

Of 5930 TAR patients, 8.4% returned to the ED within 90 days of surgery, with predisposing demographic factors identified. The highest incidence of ED visits was in the first 2 postoperative weeks, and surgical site pain was the most common reason. Pain management pathways following TAR should be able to be adjusted to minimize the occurrence of postoperative ED visits, thereby improving patient experiences and decreasing health care utilization/costs.

Level of Evidence

Level III, retrospective cohort study.

Geographic Proximity of Family Members and Healthcare Utilization After Complex Surgical Procedures

OBJECTIVE

We sought to determine the relationship between a patient's proximal familial social support, defined as the geographic proximity of family members, and healthcare utilization after complex cardiovascular and oncologic procedures.

BACKGROUND

Social support mechanisms are increasingly identified as modifiable risk factors for healthcare utilization.

METHODS

We performed a retrospective cohort study of 60,895 patients undergoing complex cardiovascular procedures or oncologic procedures. We defined healthcare utilization outcomes as 30-day all-cause readmission unplanned readmission, nonindex hospital readmission, index hospital length of stay, and home discharge disposition. For each patient, we aggregated the number of first-degree relatives (FDR) living within 30 miles of the patient's home address at the time of the surgical procedure into the following categories: 0 to 1, 2 to 3, 4 to 5, 6+ FDRs. We developed hierarchical multivariable regression models to determine the relationship between the number of FDR living within 30 miles of the patient and the healthcare utilization outcomes.

RESULTS

Compared with patients with 0 to 1 FDRs, patients with 6+ FDRs living in close proximity had significantly lower rates of all-cause readmission (12.1% vs 13.5%, P <0.001), unplanned readmission (10.9% vs 12.0%, P =0.001), nonindex readmission (2.6% vs 3.2%, P =0.003); higher rates of home discharge (88.0% vs 85.3%, P <0.001); and shorter length of stay (7.3 vs 7.5 days, P =0.02). After multivariable adjustment, a larger number of FDRs living within 30 miles of the patient was significantly associated with a lower likelihood of all-cause readmission ( P <0.001 for trend), 30-day unplanned readmission ( P <0.001), nonindex readmission ( P <0.001); higher likelihood of home discharge ( P <0.001); and shorter index length of stay ( P <0.001).

CONCLUSIONS

The geographic proximity of family members is significantly associated with decreased healthcare utilization after complex cardiovascular and oncologic surgical procedures.

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 following overlapping cases either pre-ACS guideline revision or post-guideline revision, in a coarsened exact matching (CEM) sample.

METHODS

3,327 consecutive adult patients undergoing single-level, posterior lumbar fusion from 2013-2019 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, CEM was employed among overlapping surgery patients only to assess the impact of the ACS guideline revision on overlapping outcomes, while 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- vs. post-ACS guideline revision. Similarly, when exact matched on risk-associated patient characteristics and attending surgeon, overlapping surgery patients pre- and post-ACS guideline revision experienced similar rates of 30- and 90-day outcomes.

CONCLUSION

After the ACS guideline revision, no discernable impact was observed on postoperative outcomes following lumbar fusion cases performed with overlap.

Risk Factors of Unplanned Readmission after Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-Analysis

PURPOSE

With an increasing number of anterior cervical discectomy and fusion (ACDF) being conducted for degenerative cervical disc disease, there is a rising interest in the related quality of management and healthcare costs. Unplanned readmission after ACDF affects both the quality of management and medical expenses. This meta-analysis was performed to evaluate the risk factors of unplanned readmission after ACDF to improve the quality of management and prevent increase in healthcare costs.

MATERIALS AND METHODS

We searched the databases of PubMed, EMBASE, Web of Science, and Cochrane Library to identify eligible studies using the searching terms, "readmission" and "ACDF." A total of 10 studies were included.

RESULTS

Among the demographic risk factors, older age [weighted mean difference (WMD), 3.93; 95% confidence interval (CI), 2.30-5.56; p<0.001], male [odds ratio (OR), 1.23; 95% CI, 1.10-1.36; p<0.001], and private insurance (OR, 0.34; 95% CI, 0.17-0.69; p<0.001) were significantly associated with unplanned readmission. Among patient characteristics, hypertension (HTN) (OR, 2.14; 95% CI, 1.41-3.25; p<0.001), diabetes mellitus (DM) (OR, 1.59; 95% CI, 1.20-2.11; p=0.001), coronary artery disease (CAD) (OR, 2.87; 95% CI, 2.13-3.86; p<0.001), American Society of Anesthesiologists (ASA) physical status grade >2 (OR, 2.13; 95% CI, 1.68-2.72; p<0.001), and anxiety and depression (OR, 1.39; 95% CI, 1.29-1.51; p<0.001) were significantly associated with unplanned readmission. Among the perioperative factors, pulmonary complications (OR, 22.52; 95% CI, 7.21-70.41; p<0.001) was significantly associated with unplanned readmission.

CONCLUSION

Male, older age, HTN, DM, CAD, ASA grade >2, anxiety and depression, pulmonary complications were significantly associated with an increased occurrence of unplanned readmission after ACDF.

Gender, Racial, and Ethnic Differences in the Utilization of Cervical Disk Replacement for Cervical Radiculopathy

INTRODUCTION

Cervical radiculopathy (CR) is commonly treated by spine surgeons, with surgical options including anterior cervical diskectomy and fusion (ACDF) and cervical disk replacement (CDR). CDR is a motion-sparing alternative to ACDF and was approved by the US FDA in 2007. CDR utilization has increased because evidence has emerged demonstrating its long-term efficacy. Despite CDR's efficacy, studies have suggested that socioeconomic factors may influence which patients undergo CDR versus ACDF. Our objective was to determine whether gender, racial, and ethnic disparities exist in the utilization of CDR versus ACDF for CR.

METHODS

Patients age ≥18 years undergoing elective CDR or ACDF for CR between 2017 and 2020 were identified in the Vizient Clinical Database. Proportions of patients undergoing CDR and ACDF, as well as their comorbidities, complications, and outcomes, were compared by sex, race, and ethnicity. Bonferroni correction was done for multiple comparisons.

RESULTS

A total of 7,384 patients, including 1,427 undergoing CDR and 5,957 undergoing ACDF, were reviewed. Black patients undergoing surgical treatment of CR were less likely to undergo CDR than ACDF, had a longer length of stay, and had higher readmission rates, while Hispanic patients had higher complication rates than non-Hispanic patients.

DISCUSSION

Important racial and ethnic disparities exist in CR treatment. Interventions are necessary to ensure equal access to spine care by reducing barriers, such as underinsurance and implicit bias.

LEVEL OF EVIDENCE

IV (Case Series).

Emergency department visits within 90 days of single-level anterior cervical discectomy and fusion

Background

Postoperative readmissions are a commonly used metric for quality-of-care initiatives, but emergency department (ED) visits have received far less attention despite their substantial impact on patient satisfaction and healthcare spending. The current study described the incidence and timing of ED visits following single-level ACDF, determined predictive factors and reasons for ED utilization, and compared reimbursement for patients with and without ED use.

Methods

Single-level ACDF procedures from 2010-2020 were identified in PearlDiver using CPT codes. Patients' age, sex, Elixhauser comorbidity index (ECI) score, region of the country, and insurance coverage were extracted. The incidence, timing, and primary diagnoses for 90-day ED visits and readmissions were determined, as well as total 90-day reimbursement. Variables were compared using univariate analysis and multivariate logistic regression.

Results

Out of 90,298 patients, 90-day ED visits were identified for 10,701 (11.9%), with the greatest incidence in postoperative weeks 1-2. Readmissions were identified for 3,325 (3.7%) patients. Independent predictors of ED utilization included younger age (OR 1.25 per 10-year decrease, p<0.001), greater ECI score (OR 1.40 per 2-point increase, p<0.001), and insurance type (relative to Medicare, Medicaid [OR 2.15, p<0.001] and commercial plans [OR 1.14, p=0.004]). In postoperative weeks 1-2, 51% of primary ED diagnoses involved the surgical site, while 23% involved the surgical site in weeks 3-13. Compared to patients without ED visits, those who visited the ED had 65% greater mean 90-day reimbursement (p<0.001).

Conclusions

More than three times as many patients in the current study were found to present to the ED than be readmitted within ninety days of surgery. The identified predictive factors and reasons for ED visits can direct attention to high-risk patients and common postoperative issues. Additional postoperative counseling and integrated care pathways may reduce ED visits, thereby improving patient care and reducing healthcare spending.

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

Racial Differences in Patients Undergoing Anterior Cervical Discectomy and Fusion: A Multi-Site Study

STUDY DESIGN

This was a retrospective chart review.

OBJECTIVE

The objective of this study was to examine disparities within patients undergoing anterior cervical discectomy and fusion (ACDF) at a multi-site tertiary referral center with specific focus on factors related to length of stay (LOS).

SUMMARY OF BACKGROUND DATA

There are previously described racial disparities in spinal surgery outcomes and quality metrics.

METHODS

A total of 278 consecutive patients undergoing ACDF by 8 different surgeons over a 5-year period were identified retrospectively. Demographic data, including age at time of surgery, sex, smoking status, and self-identified race [White or African American (AA)], as well as surgical data and postoperative course were recorded. Preoperative health status was recorded, and comorbidities were scored by the Charlson Comorbidity Index. Univariable and multivariable linear regression models were employed to quantify the degree to which a patient's LOS was related to their self-identified race, demographics, and perioperative clinical data.

RESULTS

Of the 278 patients who received an ACDF, 71.6% (199) self-identified as White and 28.4% (79) identified as AA. AA patients were more likely to have an ACDF due to myelopathy, while White patients were more likely to have an ACDF due to radiculopathy (P=0.001). AA patients had longer LOS by an average of half a day (P=0.001) and experienced a larger percentage of extended stays (P=0.002). AA patients experienced longer overall operation times on average (P=0.001) across all different levels of fusion. AA race was not an independent driver of LOS (β=0.186; P=0.246).

CONCLUSIONS

As hypothesized, and consistent with previous literature on racial surgical disparities, AA race was associated with increased LOS, increased operative times, and increased indication of myelopathy in this study. Additional research is necessary to evaluate the underlying social determinants of health and other factors that may contribute to this study's results.

LEVEL OF EVIDENCE

Level III.

Influence of Time of Discharge and Length of Stay on 30-Day Outcomes After Elective Anterior Cervical Spine Surgery

BACKGROUND

Encouraging early time of discharge (TOD) for medical inpatients is commonplace and may potentially improve patient throughput. It is unclear, however, whether early TOD after elective spine surgery achieves this goal without a consequent increase in re-presentations to the hospital.

OBJECTIVE

To evaluate whether early TOD results in increased rates of hospital readmission or return to the emergency department after elective anterior cervical spine surgery.

METHODS

We analyzed 686 patients who underwent elective uncomplicated anterior cervical spine surgery at a single institution. Logistic regression was used to evaluate the relationship between sociodemographic, procedural, and discharge characteristics, and the outcomes of readmission or return to the emergency department and TOD.

RESULTS

In multiple logistic regression, TOD was not associated with increased risk of readmission or return to the emergency department within 30 days of surgery. Weekend discharge (odds ratio [OR] 0.33, 95% CI 0.21-0.53), physical therapy evaluation (OR 0.44, 95% CI 0.28-0.71), and occupational therapy evaluation (OR 0.32, 95% CI 0.17-0.63) were all significantly associated with decreased odds of discharge before noon. Disadvantaged status, as measured by area of deprivation index, was associated with increased odds of readmission or re-presentation (OR 1.86, 95% CI 0.95-3.66), although this result did not achieve statistical significance.

CONCLUSION

There does not appear to be an association between readmission or return to the emergency department and early TOD after elective spine surgery. Overuse of inpatient physical and occupational therapy consultations may contribute to decreased patient throughput in surgical admissions.

Neighborhood-level Socioeconomic Status Predicts Extended Length of Stay Following Elective Anterior Cervical Spine Surgery

BACKGROUND

A significant portion of healthcare spending is driven by a small percentage of the overall population. Understanding risk factors predisposing patients to disproportionate utilization of healthcare resources is critical. Our objective was to identify risk factors leading to a prolonged length of stay (LOS) following cervical spine surgery.

METHODS

A single center cohort analysis was performed on patients who underwent elective anterior spine surgery from 2015-2021. Multivariate logistic regression evaluated the effects of sociodemographic factors including Area of Deprivation Index (quantifies income, education, employment, and housing quality), procedural, and discharge characteristics on postoperative LOS. Extended LOS was defined as greater than the 90^th percentile in midnights for the study population (greater than or equal to three midnights).

RESULTS

There were 686 patients included in the study, with a mean age of 57 years (range 26-92), median of 1 level (1-4) fused, and median LOS of 1 midnight (IQR 1,2). After adjusting for confounders, patients had increased odds of extended LOS if they were highly disadvantaged on the Area of Deprivation Index (ADI, OR=2.24, 95% CI=1.04 - 4.82; p=.039); had surgery on Thursday or Friday (OR=1.94; 1.01 - 3.72; p=.046); had a corpectomy performed (OR=2.81; 1.26 - 6.28; p=.012); or discharged not to home (OR=8.24; 2.88 - 23.56; p<.001). Patients with extended LOS were more likely to present to the emergency department or be re-admitted within 30 days after discharge (p=.024).

CONCLUSION

After adjusting for potential cofounders, patients most disadvantaged on ADI were more likely to have an extended LOS.

Clinical outcomes following one-, two-, three-, and four-level anterior cervical discectomy and fusion: a national database study

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) is a common surgical procedure. There is markedly less data on outcomes after three- and four-level cases than one- and two-level cases.

PURPOSE

To compare perioperative 90-day adverse events and 5-year reoperation rates between isolated one-, two-, three-, and four-level ACDF cases.

STUDY DESIGN/SETTING

Retrospective review of a large national database.

PATIENT SAMPLE

Overall, 97,081 patients undergoing ACDF were identified, of which one-level cases were 42,382 (43.7%), two-level cases were 24,055 (24.8%), three-level cases were 28,293 (29.1%), and four-level cases were 2,361 (2.4%).

OUTCOME MEASURES

Ninety-day adverse events and 5-year reoperation rates.

METHODS

The 2010 to Q1 2020 PearlDiver database was queried to identify patients who underwent elective ACDF for degenerative pathology without corpectomy or concomitant posterior procedures. Univariate and multivariate analyses were performed to compare outcomes of subcohorts with varying number of levels addressed by ACDF.

RESULTS

Of the 97,081 cases identified, patient characteristics and complication rates differed between the cohorts defined by levels treated. Univariate analyses revealed statistically different rates of 90-day any, serious, and minor adverse event rates between the groups, but the differences were all less than 2.5%. Readmission rates were statistically different by 2.9%, dysphagia by 3.2%, and prolonged length of stay by 6.3%.By multivariate analyses, three-level ACDF cases were not found to have greater 90-day adverse outcomes than two-level cases. Four-level ACDF cases were found to have significantly greater odds ratios of readmission, dysphagia, and prolonged length of stay (relative to one-level cases, OR 1.28, 1.63, and 1.97, respectively) but not other 90-day adverse events. Reoperation rates at five years for one-, two-, three-, and four-level cases were 13.0%, 13.5%, 15.0%, and 22.1%, respectively (log-rank p<.001).

CONCLUSIONS

The current study represents one of the largest comparative studies of patients undergoing one-, two-, three-, and four-level ACDF. While odds of 90-day adverse events were not greater for three- versus two-level cases, four-level cases had several that were higher odds than one-level cases. Reoperation and dysphagia rates were higher for four-level cases than lesser levels. While these outcomes were found to be acceptable, they should help guide hospital planning and patient counseling.

Clinical outcomes after 4- and 5-level Anterior Cervical Discectomy and Fusion for treatment of symptomatic multilevel cervical spondylosis

OBJECTIVE

There are limited patient-reported outcome measure (PROM) data on 4- and 5-level ACDF. The largest series to date solely focused on complications. This retrospective series evaluates PROMs after 4- and 5-level ACDF.

METHODS

Pertinent data from adult patients treated with a 4- or 5-level ACDF in 2011-2019 were analyzed. PROMs and minimal clinically important differences (MCID) were assessed. Factors associated with favorable and unfavorable outcomes were identified.

RESULTS

There were thirty-four patients (thirty underwent 4-level and four underwent 5-level ACDFs) with mean age of 59.6; 55.9% were women. At 3 months, there were significant improvements in PROMs except SF-12 MCS with modest improvement. At 12 months, there were significant improvements in PROMs except SF-12 PCS with moderate improvement. The proportions of patients that met the MCID cut-offs ranged from 35.3% (NRS-neck) to 75% (VR-12 PCS) at 3 months and 38.2% (NRS-arm) to 65.5% (VR-12 MCS) at 12 months. Shorter symptom duration was associated with significantly reduced postoperative pain and NDI scores. Shorter length of stay was associated with significantly improved postoperative functional outcomes. 4-level compared 5-level ACDF patients achieved better postoperative PROMs. Shorter procedure duration was associated with improved PROMs at 3 months. No patients returned to the operating room within 30 days. Patients that required reoperation achieved significantly inferior NDI, NRS-neck, and SF-12 PCS at 3 months.

CONCLUSIONS

This study demonstrated satisfactory PROMs up to 12 months after 4- and 5-level ACDF despite the complication rate. With thorough preoperative planning and meticulous technique, performing this procedure in carefully selected patients may be associated with acceptable PROM.

Variations in LOS and its main determinants overtime at an academic spinal care center from 2006-2019

Objectives

Efforts to safely reduce hospital LOS while maintaining quality outcomes and patient satisfaction are paramount. The primary goal of this study was to assess trends in LOS at a high-volume quaternary care spine center. Secondary goals were to assess trends in factors most associated with prolonged LOS.

Methods

This is a prospective study of all consecutive patients admitted from January 2006 to December 2019. Data included demographics, diagnostic category (degenerative, oncology, deformity, trauma, other), LOS (mean, median, interquartile range, standard deviation, defined as days from admission to discharge), and in-hospital adverse events.

Results

A total of 13,493 patients were included. Overall LOS has not changed over time with an overall median of 6.3 days (p = 0.451). Median LOS significantly increased for patients treated for degenerative pathology from 2.2 days in 2006 to 3.2 days in 2019 (p = 0.019). LOS has not changed for patients treated for deformity (overall median 6.8 days, p = 0.411), oncology (overall median 11.0 days, p = 0.051), or trauma (overall median 11.8 days, p = 0.582). Emergency admissions increased 3.2%/year for degenerative pathologies (p =  < 0.001). Mean age has increased from 48.4 years in 2006 to 58.1 years in 2019 (p =  < 0.001). This trend was observed in the deformity, degenerative and trauma group, not for patients treated for oncological disease. More adverse events were significantly associated with increasing age.

Conclusion

This is the first North American study to comprehensively analyze trends in LOS for spinal surgery overtime in an academic center. Overall, LOS has not changed from 2006–2019. Various factors that influence LOS appear to have balanced each other. It may also be explained by the changing epidemiology of both elective and emergency surgeries. These findings provide opportunities for intervention and improvement, targeted at the geriatric population, to reduce length of hospitalization.

Allograft Versus Autograft in Anterior Cervical Discectomy and Fusion: A Propensity-Matched Analysis

Objective

To compare the 30-day complication rate associated with allograft versus autograft in anterior cervical discectomy and fusion (ACDF) and to determine preoperative factors that may influence complication rate.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was retrospectively queried from 2014 to 2017 for all procedures with CPT codes for ACDF (22551). Patients undergoing ACDF with either autograft or allograft were matched by propensity scores based on age, sex, body mass index, and comorbidities. The incidence of adverse events in the 30-day postoperative period was compared.

Results

A total of 21,588 patients met the inclusion and exclusion criteria. Following the 10:1 propensity match, 17,061 remained in the study (1,551 autograft and 15,510 allograft). The overall adverse event rate was 3.18%; 3.48% for autograft and 3.15% for allograft (P=0.494). Autograft had a significantly greater incidence of extended length of stay (>2 d) (LOS) (48.9% vs 34.8%; P<0.001). Multivariate analysis suggested that autograft selection was associated with extended LOS (OR 1.4; 95% CI 1.3-1.5).

Conclusion

The results of this study provide information regarding how graft selection can relate to extended hospital LOS and influence postoperative complications. Extended LOS may be associated with worse patient outcomes and increase the overall cost of care. Further study should be performed to determine which patients would benefit from autograft versus allograft with regards to long-term outcomes, in consideration of these increased short-term complications.

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.

The Influence of Household Income on Survival following Posterior Fossa Tumor Resection at a Large Academic Medical Center

Objectives  The present study examines the effect of median household income on mid- and long-term outcomes in a posterior fossa brain tumor resection population. Design  This is a retrospective regression analysis. Setting  The study conducted at a single, multihospital, urban academic medical center. Participants  A total of 283 consecutive posterior fossa brain tumor cases, excluding cerebellar pontine angle tumors, over a 6-year period (June 09, 2013-April 26, 2019) was included in this analysis. Main Outcome Measures  Outcomes studied included 90-day readmission, 90-day emergency department evaluation, 90-day return to surgery, reoperation within 90 days after index admission, reoperation throughout the entire follow-up period, mortality within 90 days, and mortality throughout the entire follow-up period. Univariate analysis was conducted for the whole population and between the lowest (Q1) and highest (Q4) socioeconomic quartiles. Stepwise regression was conducted to identify confounding variables. Results  Lower socioeconomic status was found to be correlated with increased mortality within 90 postoperative days and throughout the entire follow-up period. Similarly, analysis between the lowest and highest household income quartiles (Q1 vs. Q4) demonstrated Q4 to have significantly decreased mortality during total follow-up and a decreasing but not significant difference in 90-day mortality. No significant difference in morbidity was observed. Conclusion  This study suggests that lower household income is associated with increased mortality in both the 90-day window and total follow-up period. It is possible that there is an opportunity for health care providers to use socioeconomic status to proactively identify high-risk patients and provide additional resources in the postoperative setting.

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.

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.

Significance of Hospital Size in Outcomes of Single-Level Elective Anterior Cervical Discectomy and Fusion: A Nationwide Readmissions Database Analysis

OBJECTIVE

To elucidate risk factors for 90-day readmission in anterior cervical discectomy and fusion (ACDF) for small, medium, and large hospitals. To assess differences in length of stay, charges, and complication rates across hospitals of different size.

METHODS

A retrospective analysis was performed using elective, single-level ACDF data from 2016 to 2018 in the Healthcare Cost and Utilization Project Nationwide Readmissions Database. Elective single-level ACDF cases were stratified into 3 groups by hospital bed size (small, medium, and large). All-cause complication rates, mean charges, length of stay, and 90-day readmission rates were compared across hospital size. Frequencies of specific comorbidities were compared between readmitted and nonreadmitted patients for each hospital size. Comorbidities significant on univariate analysis were evaluated as independent risk factors for 90-day readmission for each hospital size using multivariate regression.

RESULTS

The overall 90-day readmission rate was 6.43% in 36,794 patients, and the rates for small, medium, and large hospitals were 6.25%, 6.28%, and 6.56%, respectively (P = 0.537). Length of stay increased significantly with hospital size (P < 0.001), and small hospitals had the lowest charges (P < 0.001). Although different independent predictors of 90-day readmission were identified for each hospital size, cardiac arrhythmia, chronic pulmonary disease, neurologic disorders, and rheumatic disease were identified as risk factors for hospitals of all sizes.

CONCLUSIONS

Hospital size is a determining factor for charges and length of stay associated with elective single-level ACDF. Variation in risk factors for readmission exists across hospital size in context of similar 90-day readmission rates.

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.

A Novel Scoring System to Predict Length of Stay After Anterior Cervical Discectomy and Fusion

INTRODUCTION

The movement toward reducing healthcare expenditures has led to an increased volume of outpatient anterior cervical diskectomy and fusions (ACDFs). Appropriateness for outpatient surgery can be gauged based on the duration of recovery each patient will likely need.

METHODS

Patients undergoing 1- or 2-level ACDFs were retrospectively identified at a single Level I spine surgery referral institution. Length of stay (LOS) was categorized binarily as either less than two midnights or two or more midnights. The data were split into training (80%) and test (20%) sets. Two multivariate regressions and three machine learning models were developed to predict a probability of LOS ≥ 2 based on preoperative patient characteristics. Using each model, coefficients were computed for each risk factor based on the training data set and used to create a calculatable ACDF Predictive Scoring System (APSS). Performance of each APSS was then evaluated on a subsample of the data set withheld from training. Decision curve analysis was done to evaluate benefit across probability thresholds for the best performing model.

RESULTS

In the final analysis, 1,516 patients had a LOS <2 and 643 had a LOS ≥2. Patient characteristics used for predictive modeling were American Society of Anesthesiologists score, age, body mass index, sex, procedure type, history of chronic pulmonary disease, depression, diabetes, hypertension, and hypothyroidism. The best performing APSS was modeled after a lasso regression. When applied to the withheld test data set, the APSS-lasso had an area under the curve from the receiver operating characteristic curve of 0.68, with a specificity of 0.78 and a sensitivity of 0.49. The calculated APSS scores ranged between 0 and 45 and corresponded to a probability of LOS ≥2 between 4% and 97%.

CONCLUSION

Using classic statistics and machine learning, this scoring system provides a platform for stratifying patients undergoing ACDF into an inpatient or outpatient surgical setting.

Safety profile of outpatient vs inpatient ACDF: An analysis of 33,807 outpatient ACDFs

INTRODUCTION

Anterior cervical discectomy and fusion (ACDF) is commonly performed to treat symptomatic cervical spondylolysis. Recently, many spine surgeons have begun performing ACDF in the outpatient setting. However, as this is a relatively new trend, many studies are either outdated or have small sample populations. The aim of this study was to evaluate outcomes following elective outpatient ACDF in comparison to those performed in the inpatient setting.

METHODS

Patients in Mariner Claims Database (2011-2017) undergoing outpatient elective ACDF were propensity score matched using age, gender and comorbidity burden. Chronic and peri-operative complications were assigned based on medical claims codes. All outcomes of interest were analyzed using multivariate logistic regression and compared to those undergoing inpatient ACDF. Significance was defined as p < 0.05 and adjusted with Bonferroni correction.

RESULTS

Outpatient surgery had significantly lower risk of dysphagia within 24 h in both single (OR 0.44, p < 0.001) and multilevel ACDF (OR 0.48, p < 0.001). Patients undergoing outpatient procedures also have lower risk of 90-day minor (Single OR 0.64, p < 0.001; Multilevel OR 0.52, p < 0.001) and major (Single OR 0.48, p < 0.001; Multilevel OR 0.57, p < 0.001) medical complications. Outpatient procedures were also associated with decreased hospital resource utilization with a noted lower risk of subsequent hospital readmission (Single OR 0.71, p < 0.001; Multilevel OR 0.60, p < 0.001) and ER visits (Single OR 0.84, p < 0.001; Multilevel OR 0.87, p < 0.001).

CONCLUSION

Outpatient single and multilevel ACDF may be performed safely in properly selected patients. Since there are relatively low rates of readmission and significant complications within the days following outpatient ACDF, many surgeons should consider transitioning carefully selected patients to an outpatient setting.