Costs Associated With a 90-Day Episode of Care After Single-Level Anterior Lumbar Interbody Fusion

Primary Cervical Disc Arthroplasty Among Medicare Beneficiaries Versus Alternative Payers: Is It Time to Consider Nationwide Coverage?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

As of 2022, the Centers for Medicare and Medicaid Services does not provide nationwide coverage for cervical disc arthroplasty (CDA). The aim was to determine whether Medicare beneficiaries have differences in: (1) lengths of stay (LOS); (2) complications; (3) readmissions; and (4) costs of care.

METHODS

Using the 2010 to 2020 PearlDiver database, we queried patients undergoing primary CDA for degenerative disc pathology. Study groups patients were those undergoing CDA with Medicare coverage (n = 1467); patients without Medicare coverage were the comparison cohort (n = 15,389). Endpoints were to compare demographics and comorbidities within the Elixhauser comorbidity index (ECI), LOS, 90-day complications, 90-day readmissions, and 90-day reimbursements. A multivariate logistic regression was used to calculate odds (OR) of medical complications and readmissions within 90-days. A P-value less than .003 was significant.

RESULTS

Patients with Medicare coverage undergoing CDA had higher mean ECI compared to alternative payers (5.24 vs 3.26; P < .0001). Mean LOS was significantly higher for Medicare beneficiaries (2.20 vs 1.76 days; P < .010). There was no significant differences in odds of all medical complications (OR: 1.19, 95% CI: .98-1.44; P = .069) or readmission rates (1.77% vs 1.33%, OR:0.82, 95% CI: .50-1.29; P = .417) within 90-days following the index procedure among Medicare beneficiaries vs alternative payers. Non-Medicare beneficiaries had higher 90-day reimbursements compared to Medicare beneficiaries ($6,700 vs $7,086,P < .001).

CONCLUSIONS

Medicare beneficiaries despite having slightly longer lengths of stay did not have higher rates of medical complications or readmissions. Surgeons and policy makers may use this data to consider alternative treatments in Medicare patients.

The Effect of Diabetes on Complications after Spinal Fusion: A Systematic Review and Meta-Analysis

OBJECTIVE

Spinal fusion procedures are used to treat a wide variety of spinal pathologies. Diabetes mellitus (DM) has been shown to be a significant risk factor for several complications following these procedures in previous studies. To the authors' knowledge, this is the first systematic review and meta-analysis elucidating the relationship between DM and complications occurring after spinal fusion procedures.

METHODS

Systematic literature searches of PubMed and EMBASE were performed from their inception to October 1, 2022, to identify studies that directly compared postfusion complications in patients with and without DM. Studies met the prespecified inclusion criteria if they reported the following data for patients with and without DM: (1) demographics; (2) postspinal fusion complication rates; and (3) postoperative clinical outcomes. The included studies were then pooled and analyzed.

RESULTS

Twenty-eight studies, with a cumulative total of 18,853 patients (2695 diabetic patients), were identified that met the inclusion criteria. Analysis showed that diabetic patients had significantly higher rates of total number of postoperative complications (odds ratio [OR] = 1.33; 95% confidence interval [CI] = 1.12-1.58; P = 0.001), postoperative pulmonary complications (OR=2.01; 95%CI=1.31-3.08; P = 0.001), postoperative renal complications (OR=2.20; 95%CI=1.27-3.80; P = 0.005), surgical site infection (OR=2.65; 95%CI=2.19-3.20; P < 0.001), and prolonged hospital stay (OR=1.67; 95%CI=1.47-1.90; P < 0.001).

CONCLUSIONS

Patients with DM had a significantly higher risk of developing complications after spinal fusion, particularly pulmonary and renal complications, in addition to surgical site infections and had a longer length of stay. These findings are important for informed discussions of surgical risks with patients and families before surgery.

Projections of Single-level and Multilevel Spinal Instrumentation Procedure Volume and Associated Costs for Medicare Patients to 2050

BACKGROUND

Instrumented spinal fusions can be used in the treatment of vertebral fractures, spinal instability, and scoliosis or kyphosis. Construct-level selection has notable implications on postoperative recovery, alignment, and mobility. This study sought to project future trends in the implementation rates and associated costs of single-level versus multilevel instrumentation procedures in US Medicare patients aged older than 65 years in the United States.

METHODS

Data were acquired from the Centers for Medicare & Medicaid Services from January 1, 2000, to December 31, 2019. Procedure costs and counts were abstracted using Current Procedural Terminology codes to identify spinal level involvement. The Prophet machine learning algorithm was used, using a Bayesian Inference framework, to generate point forecasts for 2020 to 2050 and 95% forecast intervals (FIs). Sensitivity analyses were done by comparing projections from linear, log-linear, Poisson and negative-binomial, and autoregressive integrated moving average models. Costs were adjusted for inflation using the 2019 US Bureau of Labor Statistics' Consumer Price Index.

RESULTS

Between 2000 and 2019, the annual spinal instrumentation volume increased by 776% (from 7,342 to 64,350 cases) for single level, by 329% (from 20,319 to 87,253 cases) for two-four levels, by 1049% (from 1,218 to 14,000 cases) for five-seven levels, and by 739% (from 193 to 1,620 cases) for eight-twelve levels (P < 0.0001). The inflation-adjusted reimbursement for single-level instrumentation procedures decreased 45.6% from $1,148.15 to $788.62 between 2000 and 2019, which is markedly lower than for other prevalent orthopaedic procedures: total shoulder arthroplasty (-23.1%), total hip arthroplasty (-39.2%), and total knee arthroplasty (-42.4%). By 2050, the number of single-level spinal instrumentation procedures performed yearly is projected to be 124,061 (95% FI, 87,027 to 142,907), with associated costs of $93,900,672 (95% FI, $80,281,788 to $108,220,932).

CONCLUSIONS

The number of single-level instrumentation procedures is projected to double by 2050, while the number of two-four level procedures will double by 2040. These projections offer a measurable basis for resource allocation and procedural distribution.

Correction of Spinal Sagittal Alignment after Posterior Lumbar Decompression: Does Severity of Central Canal Stenosis Matter?

STUDY DESIGN

This study adopted a retrospective study design.

PURPOSE

Our study aimed to investigate the impact of central canal stenosis severity on surgical outcomes and lumbar sagittal correction after lumbar decompression.

OVERVIEW OF LITERATURE

Studies have evaluated sagittal correction in patients with central canal stenosis after lumbar decompression and the association of stenosis severity with worse preoperative sagittal alignment. However, none have evaluated the impact of spinal stenosis severity on sagittal correction.

METHODS

Patients undergoing posterior lumbar decompression (PLD) of ≤4 levels were divided into severe and non-severe central canal stenosis groups based on the Lee magnetic resonance imaging (MRI) grading system. Patients without preoperative MRI or inadequate visualization on radiographs were excluded. Surgical characteristics, clinical outcomes, and sagittal measurements were compared. Multivariate logistic regression was performed to determine the predictors of pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), and pelvic incidence minus lumbar lordosis (PI-LL).

RESULTS

Of the 142 patients included, 39 had severe stenosis, and 103 had non-severe stenosis. The mean follow-up duration for the cohort was 4.72 months. Patients with severe stenosis were older, had higher comorbidity indices and levels decompressed, and longer lengths of stay and operative times (p <0.001). Although those with severe stenosis had lower lordosis, lower SS, and higher PI-LL mismatch preoperatively, no differences in Delta LL, SS, PT, or PI-LL were observed between the two groups (p >0.05). On multivariate regression, severe stenosis was a significant predictor of a lower preoperative LL (estimate=-5.243, p =0.045) and a higher preoperative PI-LL mismatch (estimate=6.192, p =0.039). No differences in surgical or clinical outcomes were observed (p >0.05).

CONCLUSION

Severe central lumbar stenosis was associated with greater spinopelvic mismatch preoperatively. Sagittal balance improved in both patients with severe and non-severe stenosis after PLD to a similar degree, with differences in sagittal parameters remaining after surgery. We also found no differences in postoperative outcomes associated with stenosis severity.

Effect of Preoperative Marijuana on Patient Outcomes and Opioid Use after Lumbar Decompression

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

Our study aims to analyze the effect of preoperative marijuana use on outcomes and postoperative opioid use in patients who have undergone lumbar decompression without fusion.

METHODS

All patients >18 years of age who underwent lumbar decompression from 2017-2022 with documented preoperative marijuana use at our academic institution were retrospectively identified. A 3:1 propensity match incorporating demographics, procedure type, and levels decompressed was performed to compare preoperative marijuana users and non-users. 1-year preoperative and postoperative opioid consumption in milligrams of morphine equivalents and postoperative outcomes including readmissions, reoperations, and complications, were obtained. A multivariate regression model was performed to measure the effect of marijuana use on the likelihood of a spine reoperation.

RESULTS

Of the 340 included patients, 85 were preoperative marijuana users. There were no significant differences in medical complications, 90-day readmissions, or opioid consumption preoperatively or postoperatively (P > .05). We identified a trend towards patients who used marijuana having more reoperations for any cause (20.0% vs 11.37%, P = .067). Multivariate logistic regression analysis suggested that preoperative marijuana use was a significant predictor of all-spine reoperations (OR = 2.06, P = .036).

CONCLUSIONS

In lumbar decompression patients, preoperative marijuana use does not impact opioid consumption, readmissions, or medical complications, but is a significant predictor of future postoperative reoperations. Additional research is necessary to further explore the role of marijuana use in spine surgery.

Machine Learning Can Accurately Predict Overnight Stay, Readmission, and 30-Day Complications Following Anterior Cruciate Ligament Reconstruction

PURPOSE

This study aimed to develop machine learning (ML) models to predict hospital admission (overnight stay) as well as short-term complications and readmission rates following anterior cruciate ligament reconstruction (ACLR). Furthermore, we sought to compare the ML models with logistic regression models in predicting ACLR outcomes.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients who underwent elective ACLR from 2012 to 2018. Artificial neural network ML and logistic regression models were developed to predict overnight stay, 30-day postoperative complications, and ACL-related readmission, and model performance was compared using the area under the receiver operating characteristic curve. Regression analyses were used to identify variables that were significantly associated with the predicted outcomes.

RESULTS

A total of 21,636 elective ACLR cases met inclusion criteria. Variables associated with hospital admission included White race, obesity, hypertension, and American Society of Anesthesiologists classification 3 and greater, anesthesia other than general, prolonged operative time, and inpatient setting. The incidence of hospital admission (overnight stay) was 10.2%, 30-day complications was 1.3%, and 30-day readmission for ACLR-related causes was 0.9%. Compared with logistic regression models, artificial neural network models reported superior area under the receiver operating characteristic curve values in predicting overnight stay (0.835 vs 0.589), 30-day complications (0.742 vs 0.590), reoperation (0.842 vs 0.601), ACLR-related readmission (0.872 vs 0.606), deep-vein thrombosis (0.804 vs 0.608), and surgical-site infection (0.818 vs 0.596).

CONCLUSIONS

The ML models developed in this study demonstrate an application of ML in which data from a national surgical patient registry was used to predict hospital admission and 30-day postoperative complications after elective ACLR. ML models developed performed well, outperforming regression models in predicting hospital admission and short-term complications following elective ACLR. ML models performed best when predicting ACLR-related readmissions and reoperations, followed by overnight stay.

LEVEL OF EVIDENCE

IV, retrospective comparative prognostic trial.

The Divergence Between Hospital Charges and Reimbursements For Primary 1-2-level Lumbar Fusion Has Increased Over Time: A Medicare Administrative Claims Analysis

STUDY DESIGN

A retrospective cohort study was performed for patients undergoing 1-2-level lumbar fusion (1-2LF) from 2005 to 2014 using an administrative claims database.

OBJECTIVE

The objective of this study was to determine changes in: (1) annual charges; (2) annual reimbursement rates; and (3) annual difference (charges minus reimbursements) in patients undergoing 1-2LF.

SUMMARY OF BACKGROUND DATA

With implementation of value-based care in orthopaedics, coupled with the rise in number of patients undergoing 1-2LF, understanding the discordance in hospital charges and reimbursements is needed. The difference in hospital charges to reimbursements specifically for 1-2LF for degenerative disc disease has not been studied.

MATERIALS AND METHODS

A Medicare administrative claims database was queried for patients undergoing primary lumbar fusion using ICD-9 procedural code 81.04-81.08. Patients specifically undergoing 1-2LF were filtered from this cohort using ICD-9 procedural code 81.62. The query yielded 547,067 patients who underwent primary 1-2LF. Primary outcomes analyzed included trends in charges, reimbursement rates, and net difference in cost over time and per annual basis. Linear regression evaluated the change in costs over time with a P -value less than 0.05 considered significant.

RESULTS

From 2005 to 2014, total charges increased from $6,085,838,407 to $19,621,979,956 and total reimbursements increased from $1,677,764,831 to $4,656,702,685 (all P <0.001). Per patient charges increased 92.10% from 2005 to 2014 for patients undergoing primary 1-2LF from $129,992 to $249,697 ( P <0.001). Similarly, an increase in reimbursement per patient of 65.35% from $35,836 to $59,258 ( P <0.001) was noted. The annual difference in charges to reimbursements increased 102.26% during the study interval from $94,155 to $190,439 ( P <0.001).

CONCLUSIONS

Per patient charges and reimbursements both increased over the study period; however, charges increased 30% more than reimbursements. Further breakdown of hospital, surgeon, and anesthesiologist reimbursements for 1-2LF is needed.

LEVEL OF EVIDENCE

Level III.

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.

Demographics and Medical Comorbidities as Risk Factors for Increased Episode of Care Costs Following Lumbar Fusion in Medicare Patients

The objective was to evaluate medical comorbidities and surgical variables as independent risk factors for increased health care costs in Medicare patients undergoing lumbar fusion. Care episodes limited to lumbar fusions were retrospectively reviewed on the Centers of Medicare and Medicaid Innovation (CMMI) Bundled Payment for Care Improvement (BPCI) reimbursement database at a single academic institution. Total episode of care cost was also collected. A multivariable linear regression model was developed to identify independent risk factors for increased total episode of care cost, and logistic models for surgical complications and readmission. A total of 500 Medicare patients were included. Risk factors associated with increased total episode of care cost included transforaminal interbody fusion (TLIF) and anterior lumbar interbody fusion (ALIF) (β = $5,399, P < 0.001) and ALIF+PLF (AP) fusions (β = $24,488, P < 0.001), levels fused (β = $3,989, P < 0.001), congestive heart failure (β = $6,161, P = 0.022), hypertension with end-organ damage (β = $10,138, P < 0.001), liver disease (β = $16,682, P < 0.001), inpatient complications (β = $4,548, P = 0.001), 90-day complications (β = $10,012, P = 0.001), and 90-day readmissions (β = $15,677, P < 0.001). The most common surgical complication was postoperative anemia, which was associated with significantly increased costs (β = $18,478, P < 0.001). Female sex (OR = 2.27, P = 0.001), AP fusion (OR = 2.59, P = 0.002), levels fused (OR = 1.45, P = 0.005), cerebrovascular disease (OR = 4.19, P = 0.003), cardiac arrhythmias (OR = 2.32, P = 0.002), and fluid electrolyte disorders (OR = 4.24, P = 0.002) were independent predictors of surgical complications. Body mass index (OR = 1.07, P = 0.029) and AP fusions (OR = 2.87, P = 0.049) were independent predictors of surgical readmission. Among medical comorbidities, congestive heart failure, hypertension with end-organ damage, and liver disease were independently associated with a significant increase in total episode of care cost. Interbody devices were associated with increased admission cost.

Propensity Scored Analysis of Outpatient Anterior Lumbar Interbody Fusion: No Increased Complications

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim were to (1) evaluate differences in postoperative outcomes and cost associated with outpatient anterior lumbar interbody fusion (ALIF) compared with inpatient ALIF, and to (2) identify independent factors contributing to complications after outpatient ALIF.

SUMMARY OF BACKGROUND

While lumbar fusion is traditionally performed inpatient, outpatient spinal surgery is becoming more commonplace as surgical techniques improve.

METHODS

The study population included all patients below 85 years of age who underwent elective ALIF (CPT-22558). Patients were then divided into those who underwent single-level fusion and multilevel fusion using the corresponding additional level fusion codes (CPT-22585). These resulting populations were then split into outpatient and inpatient cohorts by using a service location modifier. To account for selection bias, propensity score matching was performed; the inpatient cohorts were matched with respect to the outpatient cohorts based on age, sex, and Charlson Comorbidity Index. Statistical significance was set at P<0.05 and the Bonferroni correction was used for each multiple comparison (P<0.004).

RESULTS

Patients undergoing outpatient procedure had decreased rates of medical complications following both single-level and multilevel ALIF. In addition, age above 60, female sex, Charlson Comorbidity Index>3, chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, hypertension, and tobacco use were all identified as independent risk factors for increased complications. Finally, the cost of outpatient ALIF was $12,013 while the cost of inpatient ALIF was $27,271 (P<0.001).

CONCLUSION

The findings add to the growing body of literature advocating for the utilization of ALIF in the outpatient setting for a properly selected group of patients.

LEVEL OF EVIDENCE

Level IV.

Supervised Machine Learning for Predicting Length of Stay After Lumbar Arthrodesis: A Comprehensive Artificial Intelligence Approach

INTRODUCTION

Few studies have evaluated the utility of machine learning techniques to predict and classify outcomes, such as length of stay (LOS), for lumbar fusion patients. Six supervised machine learning algorithms may be able to predict and classify whether a patient will experience a short or long hospital LOS after lumbar fusion surgery with a high degree of accuracy.

METHODS

Data were obtained from the National Surgical Quality Improvement Program between 2009 and 2018. Demographic and comorbidity information was collected for patients who underwent anterior, anterolateral, or lateral transverse process technique arthrodesis procedure; anterior lumbar interbody fusion (ALIF); posterior, posterolateral, or lateral transverse process technique arthrodesis procedure; posterior lumbar interbody fusion/transforaminal lumbar interbody fusion (PLIF/TLIF); and posterior fusion procedure posterior spine fusion (PSF). Machine learning algorithmic analyses were done with the scikit-learn package in Python on a high-performance computing cluster. In the total sample, 85% of patients were used for training the models, whereas the remaining patients were used for testing the models. C-statistic area under the curve and prediction accuracy (PA) were calculated for each of the models to determine their accuracy in correctly classifying the test cases.

RESULTS

In total, 12,915 ALIF patients, 27,212 PLIF/TLIF patients, and 23,406 PSF patients were included in the algorithmic analyses. The patient factors most strongly associated with LOS were sex, ethnicity, dialysis, and disseminated cancer. The machine learning algorithms yielded area under the curve values of between 0.673 and 0.752 (PA: 69.6% to 80.1%) for ALIF, 0.673 and 0.729 (PA: 66.0% to 81.3%) for PLIF/TLIF, and 0.698 and 0.749 (PA: 69.9% to 80.4%) for PSF.

CONCLUSION

Machine learning classification algorithms were able to accurately predict long LOS for ALIF, PLIF/TLIF, and PSF patients. Supervised machine learning algorithms may be useful in clinical and administrative settings. These data may additionally help inform predictive analytic models and assist in setting patient expectations.

LEVEL III

Diagnostic study, retrospective cohort study.

Antisaccades in Parkinson's Disease: A Meta-Analysis

The usefulness of eye-tracking tasks as potential biomarkers for motor or cognitive disease burden in Parkinson's disease (PD) has been subject of debate for many years. Several studies suggest that the performance in the antisaccade task may be altered in patients with PD and associated with motor disease severity or executive dysfunction. In this meta-analysis, random effects models were used to synthesize the existing evidence on antisaccade error rates and latency in PD. Furthermore, meta-regressions were performed to assess the role of motor and cognitive disease severity, dopaminergic medication and methodological factors. Additionally, the impact of acute levodopa administration and activation of deep brain stimulation was evaluated in two separate sub-analyses.This meta-analysis confirms that antisaccade latency and error rate are significantly increased in PD. Disease duration, Unified Parkinson's disease rating scale score and Hoehn and Yahr stage mediate the effect of PD on antisaccade latency with higher motor burden being associated with increased antisaccade latency.Acute administration of levodopa had no significant effects on antisaccade performance in a small number of eligible studies. Deep brain stimulation in the subthalamic nucleus, on the other hand, may alter the speed accuracy trade-off supporting an increase of impulsivity following deep brain stimulation in PD.According to the results of the meta-analysis, antisaccade latency may provide a potential marker for disease severity and progression in PD which needs further confirmation in longitudinal studies.

The Impact of Non-Elective Admission on Cost of Care and Length of Stay in Anterior Cervical Discectomy and Fusion: A Propensity-Matched Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate the impact of admission status on patient outcomes and healthcare costs in anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Undergoing ACDF non-electively has been associated with higher patient comorbidity burdens. However, the impact of non-elective status on the total cost of hospital stay has yet to be quantified.

METHODS

Patients undergoing ACDF at a single institution were placed into elective or non-elective cohorts. Propensity score-matching analysis in a 5:1 ratio controlling for insurance type and comorbidities was used to minimize selection bias. Demographics were compared by univariate analysis. Cost of care, length of stay (LOS), and clinical outcomes were compared between groups using multivariable linear and logistic regression with elective patients as reference cohort. All analyses controlled for sex, preoperative diagnosis, elixhauser comorbidity index (ECI), age, length of surgery, number of segments fused, and insurance type.

RESULTS

Of 708 patients in the final ACDF cohort, 590 underwent an elective procedure and 118 underwent a non-elective procedure. The non-elective group was significantly younger (53.7 vs. 49.5 yr; P = 0.0007). Cohorts had similar proportions of private versus public health insurance, although elective had higher rates of commercial insurance (39.22% vs. 15.25%; P < 0.0001) and non-elective had higher rates of managed care (32.77% vs. 56.78%; P < 0.0001). Operation duration was significantly longer in non-elective patients (158 vs. 177 minutes; P = 0.01). Adjusted analysis also demonstrated that admission status independently affected cost (+$6877, 95% confidence interval [CI]: $4906-$8848; P < 0.0001) and LOS (+4.9 days, 95% CI: 3.9-6.0; P < 0.0001) for the non-elective cohort. The non-elective cohort was significantly more likely to return to the operating room (OR: 3.39; 95% CI: 1.37-8.36, P = 0.0008) and experience non-home discharge (OR: 10.95; 95% CI: 5.00-24.02, P < 0.0001).

CONCLUSION

Patients undergoing ACDF non-electively had higher cost of care and longer LOS, as well as higher rates of postoperative adverse outcomes.Level of Evidence: 3.

Venous anatomy of the lumbar region applied to anterior lumbar interbody fusion (ALIF): Proposal of a new classification

Background

Anterior lumbar interbody fusion (ALIF) is a good alternative for the surgical treatment of lumbar degenerative disc disease. The primary vascular complications regarding this intervention involve the common iliac vein bifurcation complex (CIVC). Currently, no classification system allows defining which patients are more prone to these complications. We aimed to perform a retrospective study evaluating the anatomy of the common iliac CIVC at the L5-S1 disc proposing a novel classification system as it relates to the ALIF difficulty.

Methods

91 consecutive patients who underwent ALIF at the L5-S1 level were included. We categorize the CIVC at the L5-S1 disc space into four types according to the veins position along the disc space. The patient records were reviewed for demographic information, surgical characteristics, and complications. The surgical difficulty was rated at the end of the procedure.

Results

54% of the patients were women. The mean age was 52.5 ± 14.8 years. Mean surgical bleeding was 152 ml (range 20ml -3000 ml), and mean surgical time was 79 ± 13.3 minutes. Berbeo-Diaz-Vargas (BDV) classification type 4 was found in 43.9% of the patients. The surgical complexity was associated with the bleeding magnitude and surgical time spent (p<0.01), not being related to the corporal mass index or sacral slope. Bleeding magnitude, surgical time, and surgical complexity were significantly related to the BDV classification system (p<0.01). Weighted Cohen´s kappa index for the BDV scale was 0.89 (95% IC 0.822 – 0.974).

Conclusions

BDV scale is a reliable and reproducible tool for the classification of CIVC significantly related to a higher incidence of bleeding, prolonged operating time, and increased perceived difficulty by the surgeon.

Recent Trends in Medicare Utilization and Reimbursement for Orthopaedic Procedures Performed at Ambulatory Surgery Centers

BACKGROUND

As part of a market-driven response to the increasing costs of hospital-based surgical care, an increasing volume of orthopaedic procedures are being performed in ambulatory surgery centers (ASCs). The purpose of the present study was to identify recent trends in orthopaedic ASC procedure volume, utilization, and reimbursements in the Medicare system between 2012 and 2017.

METHODS

This cross-sectional, national study tracked annual Medicare claims and payments and aggregated data at the county level. Descriptive statistics and multivariate regression models were used to evaluate trends in procedure volume, utilization rates, and reimbursement rates, and to identify demographic predictors of ASC utilization.

RESULTS

A total of 1,914,905 orthopaedic procedures were performed at ASCs in the Medicare population between 2012 and 2017, with an 8.8% increase in annual procedure volume and a 10.5% increase in average reimbursements per case. ASC orthopaedic procedure utilization, including utilization across all subspecialties, is strongly associated with metropolitan areas compared with rural areas. In addition, orthopaedic procedure utilization, including for sports and hand procedures, was found to be significantly higher in wealthier counties (measured by average household income) and in counties located in the South.

CONCLUSIONS

This study demonstrated increasing orthopaedic ASC procedure volume in recent years, driven by increases in hand procedure volume. Medicare reimbursements per case have steadily risen and outpaced the rate of inflation over the study period. However, as orthopaedic practice overhead continues to increase, other Medicare expenditures such as hospital payments and operational and implant costs also must be evaluated. These findings may provide a source of information that can be used by orthopaedic surgeons, policy makers, investors, and other stakeholders to make informed decisions regarding the costs and benefits of the use of ASCs for orthopaedic procedures.

Variability and contributions to cost associated with anterior versus posterior approaches to lumbar interbody fusion

OBJECTIVE

Lumbar interbody fusions are being performed with increased frequency in the last decade. Anterior and posterior interbody techniques have demonstrated relatively similar success rates. Nonetheless, despite increased attention to cost-effective care delivery, approach-related differences in procedural cost and predictors for these differences remain poorly defined. The purpose of this investigation was to characterize the variability in cost for anterior versus posterior-based lumbar interbody fusions and to identify key predictors of procedural cost.

METHODS

We evaluated the records of all patients who underwent a primary anterior (ALIF) or posterior/transforaminal (PLIF/TLIF) lumbar interbody fusion with concomitant posterior fusion from 2016 to 2020 at four hospitals in a major metropolitan area. We reviewed the records of all included patients and abstracted demographics, insurance status, approach, operative time, diagnosis, surgeon, institution, open versus minimally invasive technique, and components of procedural costs. Costs based upon interbody approach were compared via multivariable adjusted analyses using negative binomial regression.

RESULTS

We included 139 interbody fusion procedures; 98 were performed via posterior approach (TLIF/PLIF) and 41 using an anterior approach. Anterior techniques were associated with significantly increased costs as compared to posterior procedures (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001). This determination remained significant following multivariable adjusted analysis (regression coefficient -0.22, 95% CI -0.34, -0.10, p < 0.001). Multivariable analysis also indicated that surgeon, invasiveness, and procedure time were significant predictors of total cost.

CONCLUSION

Our findings demonstrate that anterior interbody techniques are, on average, 173% (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001) more expensive than posterior-based procedures. Given the relative equipoise of these different approaches for many clinical applications, these findings should be considered in an ecosystem increasingly attentive to cost effective care delivery. This work has also provided specific procedural variables for surgeons and systems to target when optimizing procedural costs.

Using machine learning methods to predict nonhome discharge after elective total shoulder arthroplasty

Background

Machine learning has shown potential in accurately predicting outcomes after orthopedic surgery, thereby allowing for improved patient selection, risk stratification, and preoperative planning. This study sought to develop machine learning models to predict nonhome discharge after total shoulder arthroplasty (TSA).

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients who underwent elective TSA from 2012 to 2018. Boosted decision tree and artificial neural networks (ANN) machine learning models were developed to predict non-home discharge and 30-day postoperative complications. Model performance was measured using the area under the receiver operating characteristic curve (AUC) and overall accuracy (%). Multivariate binary logistic regression analyses were used to identify variables that were significantly associated with the predicted outcomes.

Results

There were 21,544 elective TSA cases identified in the National Surgical Quality Improvement Program registry from 2012 to 2018 that met inclusion criteria. Multivariate logistic regression identified several variables associated with increased risk of nonhome discharge including female sex (odds ratio [OR] = 2.83; 95% confidence interval [CI] = 2.53-3.17; P < .001), age older than 70 years (OR = 3.19; 95% CI = 2.86-3.57; P < .001), American Society of Anesthesiologists classification 3 or greater (OR = 2.70; 95% CI = 2.41-2.03; P < .001), prolonged operative time (OR = 1.38; 95% CI = 1.20-1.58; P < .001), as well as history of diabetes (OR = 1.56; 95% CI = 1.38-1.75; P < .001), chronic obstructive pulmonary disease (OR = 1.71; 95% CI = 1.46-2.01; P < .001), congestive heart failure (OR = 2.65; 95% CI = 1.72-4.01; P < .001), hypertension (OR = 1.35; 95% CI = 1.20-1.52; P = .004), dialysis (OR = 3.58; 95% CI = 2.01-6.39; P = .002), wound infection (OR = 5.67; 95% CI = 3.46-9.29; P < .001), steroid use (OR = 1.43; 95% CI = 1.18-1.74; P = .010), and bleeding disorder (OR = 1.84; 95% CI = 1.45-2.34; P < .001). The boosted decision tree model for predicting nonhome discharge had an AUC of 0.788 and an overall accuracy of 90.3%. The ANN model for predicting nonhome discharge had an AUC of 0.851 and an overall accuracy of 89.9%. For predicting the occurrence of 1 or more postoperative complications, the boosted decision tree model had an AUC of 0.795 and an overall accuracy of 95.5%. The ANN model yielded an AUC of 0.788 and an overall accuracy of 92.5%.

Conclusions

Both the boosted decision tree and ANN models performed well in predicting nonhome discharge with similar overall accuracy, but the ANN had higher discriminative ability. Based on the findings of this study, machine learning has the potential to accurately predict nonhome discharge after elective TSA. Surgeons can use such tools to guide patient expectations and to improve preoperative discharge planning, with the ultimate goal of decreasing hospital length of stay and improving cost-efficiency.

Spine Instrumented Surgery on a Budget-Tools for Lowering Cost Without Changing Outcome

STUDY DESIGN

Review article.

OBJECTIVES

There have been substantial increases in the utilization of complex spinal surgery in the last 20 years. Spinal instrumented surgery is associated with high costs as well as significant variation in approach and care. The objective of this manuscript is to identify and review drivers of instrumented spine surgery cost and explain how surgeons can reduce costs without compromising outcome.

METHODS

A literature search was conducted using PubMed. The literature review returned 217 citations. 27 publications were found to meet the inclusion criteria. The relevant literature on drivers of spine instrumented surgery cost is reviewed.

RESULTS

The drivers of cost in instrumented spine surgery are varied and include implant costs, complications, readmissions, facility-based costs, surgeon-driven preferences, and patient comorbidities. Each major cost driver represents an opportunity for potential reductions in cost. With high resource utilization and often uncertain outcomes, spinal surgery has been heavily scrutinized by payers and hospital systems, with efforts to reduce costs and standardize surgical approach and care pathways.

CONCLUSIONS

Education about cost and commitment to standardization would be useful strategies to reduce cost without compromising patient-reported outcomes after instrumented spinal fusion.

Recent trends in Medicare utilization and surgeon reimbursement for shoulder arthroplasty

BACKGROUND

Recent efforts to contain health care costs and move toward value-based health care have intensified, with a continued focus on Medicare expenditures, especially for high-volume procedures. As total shoulder arthroplasty (TSA) volume continues to increase, especially within the Medicare population, it is important for orthopedic surgeons to understand recent trends in the allocation of health care expenditures and potential effects on reimbursements. The purpose of this study was to evaluate trends in annual Medicare utilization and provider reimbursement rates for shoulder arthroplasty procedures between 2012 and 2017.

METHODS

This study tracked annual Medicare claims and payments to shoulder arthroplasty surgeons via publicly available databases and aggregated data at the county level. Descriptive statistics were used to evaluate trends in procedure volume, utilization rate (per 10,000 Medicare beneficiaries), and reimbursement rate. We used adjusted multiple linear regression models to examine associations between county-specific variables (ie, urban or rural, average household income, poverty rate, percentage Medicare population, and race and ethnicity demographics) and procedure volume, utilization rate, and reimbursement rate.

RESULTS

Between 2012 and 2017, there was an 81.3% increase in primary TSA volume and 55.5% increase in primary TSA utilization. The Midwest and South had higher utilization rates than the Northeast and West (P < .001). TSA utilization rates in metropolitan areas were significantly higher than in rural areas (P < .001). Utilization rates for primary TSA procedures also had a significant negative association with poverty rate (P < .001). Regarding reimbursements, the Medicare payment per TSA case decreased from 2012 to 2017, with overall inflation-adjusted decreases of 7.1% and 11.8% for primary and revision cases, respectively. TSAs performed in metropolitan areas received significantly higher reimbursements per case than TSAs performed in rural areas ($1108.05 and $1066.40, respectively; P = .002). Furthermore, reimbursements per case were on average higher in the Northeast and West than in the South and Midwest (P < .001).

CONCLUSIONS

Our study confirms that although TSA volume and per capita utilization have increased dramatically since 2012, Medicare Part B reimbursements to surgeons have continued to fall even after the adoption of bundled-payment models for orthopedic procedures. Cost-containment efforts continue to focus on Medicare reimbursements to surgeons, although other expenditures such as hospital payments and operational and implant costs must also be evaluated as part of an overall transition to value-based health care.

Impact of Surgical Approaches on Complications, Emergency Room Admissions, and Health Care Utilization in Patients Undergoing Lumbar Fusions for Degenerative Disc Diseases: A MarketScan Database Analysis

OBJECTIVE

To identify the impact of different surgical approaches for lumbar degenerative disc disease (DDD) on complications, reoperations/readmissions, and health care utilization.

METHODS

We used International Classification of Diseases, Ninth Revision and Tenth Revision and Current Procedural Terminology codes to extract data from MarketScan. Patients were divided into 6 groups: single-level anterior only (sA), single-level anterior + posterior (sAP), single-level posterior (sP), multilevel anterior (mA), multilevel anterior + posterior (mAP), and multilevel posterior only (mP). Outcomes of interest were cumulative complication rates, reoperation rates, readmission, and health care utilization at 6, 12, and 24 months.

RESULTS

Of 148,499 patients, 3% had sA fusion and 54% had mP procedures. Patients in the mAP cohort incurred higher cumulative complication rates (21%) compared with sA (13%), sAP (15%), sP (14%), mA (18%), and mP (18%). Emergency room admissions within 30 days were highest in the mA cohort (14%) followed by mAP (11%) and mP (8%). At 12 and 24 months, patients with mA procedures were most likely to have either new fusion or refusion (8% and 12%) followed by sA (7% and 10%), sAP (4% and 7%), mAP (4% and 8%) mP (4% and 7%), and sP (3% and 7%). Compared with the mP cohort, patients in the mA cohort incurred 1.2 times the overall median payments, whereas mAP and sA incurred 1.1 times the payments at 12 months. This difference was further reduced at 24 months.

CONCLUSIONS

mAP procedures are associated with higher cumulative complications and health care utilization compared with other procedures and the difference in health care utilization tends to decrease over 12 and 24 months.