Comparing Predictors of Complications After Anterior Cervical Diskectomy and Fusion, Total Disk Arthroplasty, and Combined Anterior Cervical Diskectomy and Fusion-Total Disk Arthroplasty With a Minimum 2-Year Follow-Up

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.

Influence of Surgeon Specialty on 30-day Outcomes Following Single-Level Cervical Disc Arthroplasty: A Propensity-Matched Analysis

STUDY DESIGN

Retrospective, propensity-matched analysis.

OBJECTIVES

Cervical disc arthroplasty (CDA) is being increasingly utilized for cervical disc generation. Surgeon specialty has been shown to influence the risk for postoperative complications in spine surgery, but this has not yet been explored for CDA. Thus, the purpose of this study is to determine whether there is any difference in 30-day complications between patients undergoing single-level CDA by neurosurgeons vs by orthopaedic surgeons.

METHODS

A retrospective, 1:1 propensity score matched analysis was performed using the NSQIP database from 2015 to 2020. Patient demographics, operative characteristics, and postoperative complications were recorded. Independent multivariate logistic regression models were constructed using the propensity-matched dataset to assess surgical specialty influence on any complication, any site complication, any operative infection, and any medical complications.

RESULTS

3179 single-level CDAs (28.8% orthopaedic surgery patients, 71.2% neurosurgery patients) were identified that met the inclusion criteria. Well-matched cohorts of 916 patients each were generated. After controlling for all possible confounders, orthopedic surgery specialty was not associated with a higher odds for any complication (OR: .87, 95% CI: .35 - 2.20, P = .7696), any site complication (OR: .32, 95% CI: .08 - 1.32, P = .1359), any operative infection (OR: .31, 95% CI: .07 - 1.34), P = .1172), nor any medical complication (OR: 2.11, 95% CI: .62 - 7.20, P = .2311) vs neurosurgery.

CONCLUSION

This is the first propensity-matched analysis to show that spine surgeon specialty does not influence the risk for any complication, any site complication, any operative infection, nor any medical complication following single-level CDA within the first 30 days after surgery.

Specialty Impact on Patient Outcomes: Paving a Way for an Integrated Approach to Spinal Disorders

Spinal surgical procedures are steadily increasing globally due to broad indications of certain techniques encompassing a wide spectrum of conditions, including degenerative spine disorders, congenital anomalies, spinal metastases, and traumatic spinal fractures. The two specialties, neurosurgery (NS) and orthopedic surgery (OS), both possess the clinical adeptness to perform these procedures. With the advancing focus on comparative effectiveness research, it is vital to compare patient outcomes in spine surgeries performed by orthopedic surgeons and neurosurgeons, given their distinct approaches and training backgrounds to guide hospital programs and physicians to consider surgeon specialty when making informed decisions. Our review of the available literature revealed no significant difference in postoperative outcomes in terms of blood loss, neurological deficit, dural injury, intraoperative complications, and postoperative wound dehiscence in procedures performed by neurosurgeons and orthopedic surgeons. An increase in blood transfusion rates among patients operated by orthopedic surgeons and a longer operative time of procedures performed by neurosurgeons was a consistent finding among several studies. Other findings include a prolonged hospital stay, higher hospital readmission rates, and lower cost of procedures in patients operated on by orthopedic surgeons. A few studies revealed lower sepsis rates unplanned intubation rates and higher incidence of urinary tract infections (UTIs) and pneumonia postoperatively among patient cohorts operated by neurosurgeons. Certain limitations were identified in the studies including the use of large databases with incomplete information related to patient and surgeon demographics. Hence, it is imperative to account for these confounding variables in future studies to alleviate any biases. Nevertheless, it is essential to embrace a multidisciplinary approach integrating the surgical expertise of the two specialties and develop standardized management guidelines and techniques for spinal disorders to mitigate complications and enhance patient outcomes.

Development and External Validation of a Risk Calculator for Prediction of Major Complications and Readmission After Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A retrospective, case-control study.

OBJECTIVE

We aim to build a risk calculator predicting major perioperative complications after anterior cervical fusion. In addition, we aim to externally validate this calculator with an institutional cohort of patients who underwent anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

The average age and proportion of patients with at least one comorbidity undergoing ACDF have increased in recent years. Given the increased morbidity and cost associated with perioperative complications and unplanned readmission, accurate risk stratification of patients undergoing ACDF is of great clinical utility.

METHODS

This is a retrospective cohort study of adults who underwent anterior cervical fusion at any nonfederal California hospital between 2015 and 2017. The primary outcome was major perioperative complication or 30-day readmission. We built standard and ensemble machine learning models for risk prediction, assessing discrimination, and calibration. The best-performing model was validated on an external cohort comprised of consecutive adult patients who underwent ACDF at our institution between 2013 and 2020.

RESULTS

A total of 23,184 patients were included in this study; there were 1886 cases of major complication or readmissions. The ensemble model was well calibrated and demonstrated an area under the receiver operating characteristic curve of 0.728. The variables most important for the ensemble model include male sex, medical comorbidities, history of complications, and teaching hospital status. The ensemble model was evaluated on the validation cohort (n=260) with an area under the receiver operating characteristic curve of 0.802. The ensemble algorithm was used to build a web-based risk calculator.

CONCLUSION

We report derivation and external validation of an ensemble algorithm for prediction of major perioperative complications and 30-day readmission after anterior cervical fusion. This model has excellent discrimination and is well calibrated when tested on a contemporaneous external cohort of ACDF cases.

National Rates, Reasons, and Risk Factors for 30- and 90-Day Readmission and Reoperation Among Patients Undergoing Anterior Cervical Discectomy and Fusion: An Analysis Using the Nationwide Readmissions Database

STUDY DESIGN

Retrospective cohort study of the Nationwide Readmissions Database (NRD).

OBJECTIVE

To determine causes of and independent risk factors for 30- and 90-day readmission in a cohort of anterior cervical discectomy and fusion (ACDF) patients.

SUMMARY OF BACKGROUND DATA

Identifying populations at high-risk of 30-day readmission is a priority in healthcare reform so as to reduce cost and patient morbidity. However, among patients undergoing ACDF, nationally-representative data have been limited, and have seldom described 90-day readmissions, early reoperation, or socioeconomic influences.

METHODS

We queried the NRD, which longitudinally tracks 49.3% of hospitalizations, for all adult patients undergoing ACDF. We calculated the rates of, and determined reasons for, readmission and reoperation at 30 and 90 days, and determined risk factors for readmission at each timepoint.

RESULTS

We identified 50,126 patients between January and September 2014. Of these, 2294 (4.6%) and 4152 (8.3%) were readmitted within 30 and 90 days of discharge, respectively, and were most commonly readmitted for infections, medical complications, and dysphagia. The characteristics most strongly associated with readmission were Medicare or Medicaid insurance, length of stay greater than or equal to 4 days, three or more comorbidities, and non-routine discharge, whereas surgical factors (e.g., greater number of vertebrae fused) were more modest. By 30 and 90 days, 8.2% and 11.7% of readmitted patients underwent an additional spinal procedure, respectively.

CONCLUSION

Our analysis uses the NRD to thoroughly characterize readmission in the general ACDF population. Readmissions are often delayed (after 30 days), strongly associated with insurance status, and many result in reoperation. Our results are crucial for risk-stratifying future ACDF patients and developing interventions to reduce readmission.Level of Evidence: 3.

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.