Large Rises in Thoracolumbar Fusions by 2040: A Cause for Concern with an Increasingly Elderly Surgical Population

Trends, costs, and complications associated with after-hours surgery and unscheduled hospitalization in spinal surgery

Aims

The escalating demand for medical resources to address spinal diseases as society ages is an issue that requires careful evaluation. However, few studies have examined trends in spinal surgery, especially unscheduled hospitalizations or surgeries performed after hours, through large databases. Our study aimed to determine national trends in the number of spine surgeries in Japan. We also aimed to identify trends in after-hours surgeries and unscheduled hospitalizations and their impact on complications and costs.

Methods

We retrospectively investigated data extracted from the Diagnosis Procedure Combination database, a representative inpatient database in Japan. The data from April 2010 to March 2020 were used for this study. We included all patients who had undergone any combination of laminectomy, laminoplasty, discectomy, and/or spinal arthrodesis.

Results

This investigation included 739,474 spinal surgeries and 739,215 hospitalizations in Japan. There was an average annual increase of 4.6% in the number of spinal surgeries. Scheduled hospitalizations increased by 3.7% per year while unscheduled hospitalizations increased by 11.8% per year. In-hours surgeries increased by 4.5% per year while after-hours surgeries increased by 9.9% per year. Complication rates and costs increased for both after-hours surgery and unscheduled hospitalizations, in comparison to their respective counterparts of in-hours surgery and scheduled hospitalizations.

Conclusion

This study provides important insights for those interested in improving spine care in an ageing society. The swift surge in after-hours spinal surgeries and unscheduled hospitalizations highlights that the medical needs of an increasing number of patients due to an ageing society are outpacing the capacity of existing medical resources.

Racial Disparities in Outcomes Following Surgical Fixation of Traumatic Thoracolumbar Fractures: A National Database Analysis

OBJECTIVE

This study aims to assess race as an independent risk factor for postoperative complications after surgical fixation of traumatic thoracolumbar fractures for African American and Asian American patients compared with White patients.

METHODS

The 2011-2021 American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) dataset was used to identify patients undergoing fusion surgeries for thoracolumbar spine fractures. Patient comorbidity burden was assessed using a modified 5-item frailty index score (mFI-5). Chi-squared and ANOVA tests were used to compare baseline clinical characteristics between groups. Multivariate analysis was performed to compare African American and Asian American patients with White patients controlling for age, BMI, and American Society of Anesthesiologists (ASA) score.

RESULTS

African American patients experienced longer operative times compared to Asian American and White patients (3.74 ± 1.87 hours vs. 3.04 ± 1.71 hours and 3.48 ± 1.81 hours, P < 0.001). African American and Asian American patients demonstrated higher comorbidity burden with mFI-5>2 compared to White patients (30.7% and 25.6% vs. 19.9%, P < 0.001). African American and Asian American patients had a higher risk of postoperative complications than White patients (22.4% and 20% vs. 19.7%, P < 0.001). African American race was an independent risk factor of postoperative 30-day morbidity (OR 1.19, CI 1.11-1.28, P < 0.001).

CONCLUSIONS

African American and Asian American patients undergoing thoracolumbar fusion surgeries exhibit disproportionate comorbidity burden, longer LOS, and greater postoperative complications compared with White patients. Furthermore, the African American race was associated with an increased rate of 30-day postoperative complications.

Cyclic testing of standalone ALIF versus TLIF in lumbosacral spines of low bone mineral density: an ex vivo biomechanical study

PURPOSE

Screwed anterior lumbar interbody fusion (SALIF) alleviates the need for supplemental posterior fixation leading to reduction of perioperative morbidity. Specifically, elderly and multimorbid patients would benefit from shorter operative time and faster recovery but tend to have low bone mineral density (BMD). The current study aimed to compare loosening, defined as increase of ROM and NZ, of SALIF versus transforaminal lumbar interbody fusion (TLIF) under cyclic loading in cadaveric spines with reduced BMD.

METHODS

Twelve human spines (L4-S2; 6 male 6 female donors; age 70.6 ± 19.6; trabecular BMD of L5 84.2 ± 24.4 mgHA/cm3, range 51-119 mgHA/cm3) were assigned to two groups. SALIF or TLIF were instrumented at L5/S1. Range of motion (ROM) and neutral zone (NZ) were assessed before and after axial cyclic loading (0-1150 N, 2000 cycles, 0.5 Hz) in flexion-extension (Flex-Ext), lateral bending, (LB), axial rotation (AR).

RESULTS

ROM of the SALIF specimens increased significantly in all loading directions (p ≤ 0.041), except for left AR (p = 0.053), whereas for TLIF it increased significantly in left LB (p = 0.033) and Flex (p = 0.015). NZ of SALIF showed increase in Flex-Ext and LB, whereas NZ of TLIF did not increase significantly in any motion direction.

CONCLUSIONS

Axial compression loading caused loosening of SALIF in Flex-Ext and LB, but not TLIF at L5/S1 in low BMD specimens. Nevertheless, Post-cyclic ROM and NZ of SALIF is comparable to TLIF. This suggests that, neither construct is optimal for the use in patients with reduced BMD.

Formal Radiologist Interpretations of Intraoperative Spine Radiographs Have Low Clinical Value

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To evaluate the clinical relevance, usefulness, and financial implications of intraoperative radiograph interpretation by radiologists in spine surgery.

SUMMARY OF BACKGROUND DATA

Due to rising health care costs, spine surgery is under scrutiny to maximize value-based care. Formal radiographic analysis remains a potential source of unnecessary health care costs, especially for intraoperative radiographs.

MATERIALS AND METHODS

A retrospective cohort analysis was performed on all adult elective spine surgeries at a single institution between July 2020 and July 2021. Demographic and radiographic data were collected, including intraoperative localization and post-instrumentation radiographs. Financial data were obtained through the institution's price estimator. Radiographic characteristics included time from radiographic imaging to completion of radiologist interpretation report, completion of radiologist interpretation report before the conclusion of surgical procedure, clinical relevance, and clinical usefulness. Reports were considered clinically relevant if the spinal level of the procedure was described and clinically useful if completed before the conclusion of the procedure and deemed clinically relevant.

RESULTS

Four hundred eighty-one intraoperative localization and post-instrumentation radiographs from 360 patients revealed a median delay of 128 minutes between imaging and completion of the interpretive report. Only 38.9% of reports were completed before the conclusion of surgery. There were 79.4% deemed clinically relevant and only 33.5% were clinically useful. Localization reports were completed more frequently before the conclusion of surgery (67.2% vs. 34.4%) but with lower clinical relevance (90.1% vs. 98.5%) and clinical usefulness (60.3% vs. 33.6%) than post-instrumentation reports. Each patient was charged $32 to $34 for the interpretation fee, cumulating a minimum total cost of $15,392.

CONCLUSIONS

Formal radiographic interpretation of intraoperative spine radiographs was of low clinical utility for spine surgeons. Institutions should consider optimizing radiology workflows to improve timeliness and clinical relevance or evaluate the necessity of reflexive consultation to radiology for intraoperative imaging interpretation to ensure that value-based care is maximized during spine surgeries.

LEVEL OF EVIDENCE

3.

Evaluation of perioperative care and drivers of cost in geriatric thoracolumbar trauma

Introduction

As the population of elderly patients continues to rise, the number of these individuals presenting with thoracolumbar trauma is expected to increase.

Research question

To investigate thoracolumbar fusion outcomes for patients with vertebral fractures as stratified by decade. Secondarily, we examined the variability of cost across age groups by identifying drivers of cost of care.

Materials and methods

We queried the United States Nationwide Inpatient Sample(NIS) for adult patients undergoing spinal fusion for thoracolumbar fractures between 2012 and 2017. Patients were stratified by decade 60-69(sexagenarians), 70-79(septuagenarians) and 80-89(octogenarians). Bivariable analysis followed by multivariable regression was performed to assess independent predictors of length of stay(LOS), hospital cost, and discharge disposition.

Results

A total of 2767 patients were included, of which 46%(N = 1268) were sexagenarians, 36% septuagenarians and 18%(N = 502) octogenarians. Septuagenarians and octogenarians had shorter LOS compared to sexagenarians(ß = -0.88 days; p = 0.012) and(ß = -1.78; p < 0.001), respectively. LOS was reduced with posterior approach(-2.46 days[95% CI: 3.73-1.19]; p < 0.001), while Hispanic patients had longer LOS(+1.97 [95% CI: 0.81-3.13]; p < 0.001). Septuagenarians had lower total charges $12,185.70(p = 0.040), while the decrease in charges in octogenarians was more significant, with a decrease of $26,016.30(p < 0.001) as compared to sexagenarians. Posterior approach was associated with a decrease of $24,337.90 in total charges(p = 0.026). Septuagenarians and octogenarians had 1.72 higher odds(p < 0.001) and 4.16 higher odds(p < 0.001), respectively, of discharge to a skilled nursing facility.

Discussion and conclusions

Healthcare utilization in geriatric thoracolumbar trauma is complex. Cost reductions in the acute hospital setting may be offset by unaccounted costs after discharge. Further research into this phenomenon and observed racial/ethnic disparities must be pursued.

The Effect of Preoperative Marijuana Use on Surgical Outcomes, Patient-Reported Outcomes, and Opioid Consumption Following Lumbar Fusion

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To (1) investigate the effect of marijuana use on surgical outcomes following lumbar fusion, (2) determine how marijuana use affects patient-reported outcomes measures (PROMs), and (3) determine if marijuana use impacts the quantity of opioids prescribed.

METHODS

Patients > 18 years of age who underwent primary one- or two-level lumbar fusion with preoperative marijuana use at our institution were identified. A 3:1 propensity match incorporating patient demographics and procedure type was conducted to compare preoperative marijuana users to non-marijuana users. Patient demographics, surgical characteristics, surgical outcomes (90-day all-cause and 90-day surgical readmissions, reoperations, and revision surgeries), pre- and postoperative narcotic usage, and PROMs were compared between groups. Multivariate regression models were created to determine the effect of marijuana on surgical reoperations patient-reported outcomes (PROMs) 1-year postoperatively.

RESULTS

Of the 259 included patients, 65 used marijuana preoperatively. Multivariate logistic regression analysis demonstrated that marijuana use (OR = 2.28, P = .041) significantly increased the likelihood of having a spine reoperation. No other surgical outcome was found to be significantly different between groups. Multivariate linear regression analysis showed that marijuana use was not significantly associated with changes in 1-year postoperative PROMs (all, P > .05). The quantity of pre- and postoperative opioids prescriptions was not significantly different between groups (all, P > .05).

CONCLUSIONS

Preoperative marijuana use increased the likelihood of a spine reoperation for any indication following lumbar fusion, but it was not associated with 90-day all cause readmission, surgical readmission, the magnitude of improvement in PROMs, or differences in opioid consumption.

LEVEL OF EVIDENCE

III.

Weekend Admission Increases Risk of Readmissions Following Elective Thoracolumbar Spinal Fusion

STUDY DESIGN

Retrospective database study.

OBJECTIVES

The goal of this study was to assess the influence of weekend admission on patients undergoing elective thoracolumbar spinal fusion by investigating hospital readmission outcomes and analyzing differences in demographics, comorbidities, and postoperative factors.

METHODS

The 2016-2018 Nationwide Readmission Database was used to identify adult patients who underwent elective thoracolumbar spinal fusion. The sample was divided into weekday and weekend admission patients. Demographics, comorbidities, complications, and discharge status data were compiled. The primary outcomes were 30-day and 90-day readmission. Univariate logistic regression analyzed the relationship between weekday or weekend admission and 30- or 90-day readmission, and multivariate regression determined the impact of covariates.

RESULTS

177,847 patients were identified in total, with 176,842 in the weekday cohort and 1005 in the weekend cohort. Multivariate regression analysis found that 30-day readmissions were significantly greater for the weekend cohort after adjusting for sex, age, Medicare or Medicaid status, and comorbidity status (OR 2.00, 95% CI: 1.60-2.48; P < .001), and 90-day readmissions were also greater for the weekend cohort after adjustment (OR 2.01, 95% CI: 1.68-2.40, P < .001).

CONCLUSIONS

Patients undergoing elective thoracolumbar spinal fusion surgery who are initially admitted on weekends are more likely to experience hospital readmission. These patients have increased incidence of deep vein thrombosis, postoperative infection, and non-routine discharge status. These factors are potential areas of focus for reducing the impact of the "weekend effect" and improving outcomes for elective thoracolumbar spinal fusion.

Anesthesia practice among joint arthroplasty patients with a previous lumbar spine surgery

STUDY OBJECTIVE

To analyze the use of neuraxial techniques in total hip or knee arthroplasty patients who previously underwent lumbar spine surgeries.

DESIGN

Retrospective analysis of a national database.

SETTING

U.S. hospitals.

PATIENTS

Patients undergoing a total hip or knee arthroplasty, stratified by those with a previous lumbar fusion or decompression procedure.

MEASUREMENTS

Our primary outcome was the use of neuraxial anesthesia; secondary outcomes included combined complications, cardio-pulmonary complications, and prolonged length of stay. Patients with and without a history of a lumbar procedure were compared using mixed-effects regression.

MAIN RESULTS

Among 758,857 THAs 8961 had a history of lumbar fusion and 8599 of decompression. Among 1,387,335 TKAs 15,827 had a history of lumbar fusion and 13,652 of decompression. History of a lumbar fusion was associated with lower odds of neuraxial anesthesia use in THA (OR: 0.74 CI: 0.70-0.79, p ≤0.0001) and TKA (OR: 0.80 CI: 0.77-0.84, p ≤0.0001).

CONCLUSIONS

Previous lumbar fusion -but not decompression- surgery is associated with lower neuraxial anesthesia in THA/TKA patients, despite its use being universally associated with decreased length of stay. More research is needed to address the importance of neuraxial techniques in patients with prior spine surgery.

The severity of preoperative anemia escalates risk of poor short-term outcomes after lumbar spine fusion

OBJECTIVE

To evaluate how preoperative anemia severity affects 90-day outcomes of spinal fusion surgery.

METHODS

A retrospective cohort study was conducted on adult lumbar fusion patients at a tertiary medical center. Patients were classified by World Health Organization anemia severity definitions for comparisons. Multivariate regression models were created to control for confounding variables, for all primary outcomes of transfusion requirements, non-home discharge, readmissions, complications, and length of stay.

RESULTS

A total of 2582 patients were included: 2.7% with moderate-severe anemia, 11.0% with mild anemia, and 86.3% without anemia. Moderate-severe patients had the longest hospital stay (5.03 days vs 4.14 and 3.59 days, p < 0.001) and highest risk of transfusion (52.2% vs 13.0% vs 2.69%, p < 0.001), non-home discharge (39.1% vs 27.8% vs 15.4%, p < 0.001), readmission (7.25% vs 5.99% vs 3.36%, p = 0.023), and complications (13.0% vs 9.51% vs 6.20%, p = 0.012). On multivariable logistic regression, both patients with mild and moderate-severe anemia had an increased risk of transfusion (OR: 37.3, p < 0.001; OR: 5.25, p < 0.001, respectively) and non-home discharge (OR: 2.00, p = 0.021; OR: 1.71, p = 0.001, respectively) compared to patients without anemia. Anemia severity was not independently associated with complications or 90-day readmission. On multivariable linear regression, mild anemia (β: 0.37, p = 0.001) and moderate-severe anemia (β: 1.07, p < 0.001) were independently associated with length of hospital stay.

CONCLUSION

Patients with moderate-severe preoperative anemia are at increased risk for longer length of stay, transfusions, and non-home discharge. Improved optimization of preoperative anemia may significantly reduce healthcare utilization, and surgeons should consider these risks in preoperative planning.

LEVEL OF EVIDENCE

III.

Recent Trends in Spine Topics on the Orthopaedic In-Training Examination

INTRODUCTION

The Orthopaedic In-Training Examination (OITE) is an important metric for orthopaedic residents and residency programs to gauge a resident's orthopaedic knowledge. Because the OITE is correlated with the likelihood of passing part I of the American Board of Orthopaedic Surgery, greater emphasis is being placed on the examination. However, a detailed look at the questions most likely to appear on the spine subsection of the OITE has not been done in the past decade.

METHODS

Digital copies of the OITEs during the years 2017 through 2021 were obtained online through the "ResStudy" program within the American Academy of Orthopaedic Surgeons Online Learning Platform. All spine-related questions were categorized into five different categories including type of spine question (knowledge-based, diagnosis, or evaluation/management), anatomical region, imaging modality provided, subject matter, and referenced journal or textbook. The total number and likelihood of each question type to appear on the OITE were defined as mean and percentage of the total number of spine questions, respectively.

RESULTS

A total of 139 spine questions were identified on the OITE during the years 2017 to 2021. The most common type of spine questions were evaluation/management (N = 65) and knowledge-based questions. We identified lumbar (N = 45), cervical (N = 42), thoracolumbar (N = 13), and thoracic (N = 12) as the most commonly tested anatomical regions. Spinal trauma (N = 26), disk disease/disk herniation (N = 16), postoperative complications (N = 15), and scoliosis/sagittal balance (N = 15) were the most commonly tested material. Spine (N = 54) was almost two times more likely to be referenced as the source for the tested material compared with other journals or textbooks.

CONCLUSIONS

Understanding the spine topics most likely to appear on the OITE may allow orthopaedic residents and residency programs to supplement educational objectives toward the highest yield spine topics and journals.

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.

Trends in Single-Level Lumbar Fusions Over the Past Decade Using a National Database

OBJECTIVE

To compare rates of different fusion techniques using a nationwide database over the last decade and identify differences in complications and readmissions based on fusion technique.

METHODS

All elective, single-level lumbar fusions performed by orthopaedic surgeons from 2011 to 2020 were identified from the American College of Surgeons National Surgical Quality Improvement Program. Rates of lumbar fusion technique posterolateral decompression and fusion [PLDF], combined transforaminal lumbar interbody fusion and PLDF, anterior lumbar or lateral lumbar interbody fusion [ALIF/LLIF], and combined ALIF/LLIF and PLDF were recorded, and 30-day complications and readmissions were compared. Secondary analysis included multiple logistic regression to determine independent predictors of each outcome.

RESULTS

Inclusion criteria were met by 28,413 fusions: 8749 (30.8%) PLDFs, 11,973 (42.1%) transforaminal lumbar interbody fusions, 4769 (16.8%) ALIF/LLIFs, and 2922 (10.3%) combined ALIF/LLIF and PLDFs. The number of fusions increased over time with 1227 fusions performed in 2011 and 3958 fusions performed in 2019. Interbody fusions also increased over time with a subsequent decrease in PLDFs (39.0% in 2011, 25.2% in 2020). Patients were more likely to be discharged home over the course of the decade (85.4% in 2011, 95.0% in 2020). No difference was observed between the techniques regarding complications or readmissions. The modified 5-item frailty index was predictive of complications (odds ratio, 2.05; P = 0.001) and readmissions (odds ratio, 2.61; P < 0.001).

CONCLUSIONS

Lumbar fusions have continued to increase over the last decade with an increasing proportion of interbody fusions. Complications and readmissions appear to be driven by patient comorbidity and not fusion technique.

Clinical Trial Quality Assessment in Adult Spinal Surgery: What Do Publication Status, Funding Source, and Result Reporting Tell Us?

STUDY DESIGN

Narrative Review.

OBJECTIVES

The objective of this study was to compare publication status of clinical trials in adult spine surgery registered on ClinicalTrials.gov by funding source as well as to identify other trends in clinical trials in adult spine surgery.

METHODS

All prospective, comparative, therapeutic (intervention-based) trials of adult spinal disease that were registered on ClinicalTrials.gov with a start date of January 1, 2000 and completion date before December 17, 2018 were included. Primary outcome was publication status of published or unpublished. A bivariate analysis was used to compare publication status to funding source of industry vs non-industry.

RESULTS

Our search identified 107 clinical trials. The most common source of funding was industry (62 trials, 57.9% of total), followed by University funding (26 trials, 24.3%). The results of 76 trials (71.0%) were published, with industry-funded trials less likely to be published compared to non-industry-funded trials (62.9% compared to 82.2%, P = .03). Of the 31 unpublished studies, 13 did not report any results on ClinicalTrials.gov, and of those with reported results, none was a positive trial.

CONCLUSIONS

Clinician researchers in adult spine surgery should be aware that industry-funded trials are less likely to go on to publication compared to non-industry-funded trials, and that negative trials are frequently not published. Future opportunities include improvement in result reporting and in publishing negative studies.

Recent Trends in Private Equity Acquisition of Orthopaedic Practices in the United States

BACKGROUND

Private equity acquisition of medical specialty practices has increased in recent years. With the projected increase in the volume of elective, ambulatory orthopaedic procedures, especially in the outpatient setting, private equity firms are increasingly investing in orthopaedic practices. The purpose of this cross-sectional study was to report recent trends and variations in acquisitions of US orthopaedic practices by private equity firms and other institutional investors (venture capital firms, trusts, and large investment companies).

METHODS

Acquisition data through January 1, 2020, were collected and analyzed using various financial databases, supplemented with publicly available information from financial news outlets, press releases, and financial analyst and industry reports. Disclosed financing data were also included, in addition to pertinent geographic information (state, city, and zip code) of the target practices.

RESULTS

Between 2004 and 2019, 41 orthopaedic practices and surgeon groups across 22 states were acquired by 34 private equity and other investment firms. A significant increase was observed in the number of acquisitions between 2017 and 2019, consisting of 70.7% of total transactions during the study period, with a statistically significant upward yearly trend (P = 0.002). The compound annual growth rate in acquisition volume was 29.2% during the study period. A disproportionate share of private equity acquisitions took place in the South, where more than half (51.2%) of the total transactions took place. Firms were markedly more likely to acquire or invest in practices located in major metropolitan areas (population more than 1 million) compared with those in mid-sized or rural areas (70.7%, 17.1%, 12.2%, respectively; P < 0.001).

CONCLUSIONS

Private equity acquisition of orthopaedic surgery practices has increased markedly in recent years. The effect of private equity acquisition on physician independence, practice management, and procedure reimbursement remains unclear and may be important to explore as practice management evolves.

LEVEL OF EVIDENCE

Prognostic Level III.