30- and 90-Day Unplanned Readmission Rates, Causes, and Risk Factors After Cervical Fusion: A Single-Institution Analysis

Minimally Invasive Posterior Cervical Fusion Strategies

Thoracolumbar minimally invasive spine surgery (MIS) has become widely adopted over the past two decades. MIS cervical fixation has lagged behind, largely because of complex and variable cervical spinal anatomy. Traditional open spine fixation techniques are associated with high fusion rates but are plagued by significant approach-related morbidity. This morbidity is due to paraspinal muscle denervation and atrophy secondary to disruption of the posterior musculoligamentous complex leading to wound healing difficulties, including relatively high rates of wound infection and dehiscence as well as aesthetic issues. Therefore, novel MIS fixation techniques have focused on percutaneous tissue-sparing approaches in an effort to decrease wound morbidity and hospital readmission. In addition, more biomechanically robust minimally invasive constructs may provide smaller alternative surgical solutions. Previously described fluoroscopic MIS cervical pedicle screw placement has been revitalized with the recent description of a navigated percutaneous minimally invasive technique. With the incorporation of new enabling navigation technologies, this technique is feasible, reproducible, and safe. In addition, these procedures have provided unique solutions for approaching cervical pathology in line with currently accepted MIS principles of the thoracolumbar spine. This review article discusses current minimally invasive posterior fusion strategies with a description of the technique and case demonstrations.

Perioperative and safety outcomes following tissue-sparing posterior cervical fusion to revise a pseudarthrosis: A multicenter retrospective review of 150 cases

Background

Posterior cervical fusion (PCF) with lateral mass screws is a favorable treatment option to revise a symptomatic pseudarthrosis due to reliable rates of arthrodesis; however, this technique introduces elevated risk for wound infection and hospital readmission. A tissue-sparing PCF approach involving facet fixation instrumentation reduces the rates of postoperative complications while stabilizing the symptomatic level to achieve arthrodesis; however, these outcomes have been limited to small study cohorts from individual surgeons commonly with mixed indications for treatment.

Materials and Methods

One hundred and fifty cases were identified from a retrospective chart review performed by seven surgeons across six sites in the United States. All cases involved PCF revision for a pseudarthrosis at one or more levels from C3 to C7 following anterior cervical discectomy and fusion (ACDF). PCF was performed using a tissue-sparing technique with facet instrumentation. Cases involving additional supplemental fixation such as lateral mass screws, rods, wires, or other hardware were excluded. Demographics, operative notes, postoperative complications, hospital readmission, and subsequent surgical interventions were summarized as an entire cohort and according to the following risk factors: age, sex, number of levels revised, body mass index (BMI), and history of nicotine use.

Results

The average age of patients at the time of PCF revision was 55 ± 11 years and 63% were female. The average BMI was 29 ± 6 kg/m2 and 19% reported a history of nicotine use. Postoperative follow-up visits were available with a median of 68 days (interquartile range = 41-209 days) from revision PCF. There were 91 1-level, 49 2-level, 8 3-level, and 2 4±-level PCF revision cases. The mean operative duration was 52 ± 3 min with an estimated blood loss of 14 ± 1.5cc. Participants were discharged an average of 1 ± 0.05 days following surgery. Multilevel treatment resulted in longer procedure times (single = 45 min, multi = 59 min, P = 0.01) but did not impact estimated blood loss (P = 0.94). Total nights in the hospital increased by 0.2 nights with multilevel treatment (P = 0.01). Sex, age, nicotine history, and BMI had no effect on recorded perioperative outcomes. There was one instance of rehospitalization due to deep-vein thrombosis, one instance of persistent pseudarthrosis at the revised level treated with ACDF, and four instances of adjacent segment disease. In patients initially treated with multilevel ACDF, revisions occurred most commonly on the caudal level (48% of revised levels), followed by the cranial (43%), and least often in the middle level (9%).

Conclusions

This chart review of perioperative and safety outcomes provides evidence in support of tissue-sparing PCF with facet instrumentation as a treatment for symptomatic pseudarthrosis after ACDF. The most common locations requiring revision were the caudal and cranial levels. Operative duration and estimated blood loss were favorable when compared to open alternatives. There were no instances of postoperative wound infection, and the majority of patients were discharged the day following surgery.

Previous Emergency Department Admission Is Associated With Increased 90-Day Readmission Following Cervical Spine Surgery: Evidenced Using Propensity Score Matching

STUDY DESIGN

This was a retrospective case-control study.

OBJECTIVE

The objective of this study was to evaluate whether prior emergency department admission was associated with an increased risk for 90-day readmission following elective cervical spinal fusion.

SUMMARY OF BACKGROUND DATA

The incidence of cervical spine fusion reoperations has increased, necessitating the improvement of patient outcomes following surgery. Currently, there are no studies assessing the impact of emergency department visits before surgery on the risk of 90-day readmission following elective cervical spine surgery. This study aimed to fill this gap and identify a novel risk factor for readmission following elective cervical fusion.

METHODS

The 2016-2018 Nationwide Readmissions Database was queried for patients aged 18 years and older who underwent an elective cervical fusion. Prior emergency admissions were defined using the variable HCUP_ED in the Nationwide Readmissions Database database. Univariate analysis of patient demographic details, comorbidities, discharge disposition, and perioperative complication was evaluated using a χ 2 test followed by multivariate logistic regression.

RESULTS

In all, 2766 patients fit the inclusion criteria, and 18.62% of patients were readmitted within 90 days. Intraoperative complications, gastrointestinal complications, valvular, uncomplicated hypertension, peripheral vascular disorders, chronic obstructive pulmonary disease, cancer, and experiencing less than 3 Charlson comorbidities were identified as independent predictors of 90-day readmission. Patients with greater than 3 Charlson comorbidities (OR=0.04, 95% CI 0.01-0.12, P <0.001) and neurological complications (OR=0.29, 95% CI 0.10-0.86, P =0.026) had decreased odds for 90-day readmission. Importantly, previous emergency department visits within the calendar year before surgery were a new independent predictor of 90-day readmission (OR=9.74, 95% CI 6.86-13.83, P <0.001).

CONCLUSIONS

A positive association exists between emergency department admission history and 90-day readmission following elective cervical fusion. Screening cervical fusion patients for this history and optimizing outcomes in those patients may reduce 90-day readmission rates.

Late Retropharyngeal and Parapharyngeal Abscess in Patients with a History of Anterior Cervical Discectomy and Fusion

OBJECTIVE

Anterior cervical discectomy and fusion is a common procedure performed by spine surgeons with rare complications and high treatment success. Late presentation of retropharyngeal abscess in patients with a history of anterior cervical discectomy and fusion is rare but can have devastating consequences. There is a paucity of data to guide medical and surgical management of retropharyngeal abscess in these patients.

METHODS

We discuss 7 patients who presented to our institution with a late retropharyngeal abscess after having a history of anterior cervical discectomy and fusion. A review and description of the current literature regarding treatment and outcomes is described.

RESULTS

Seven patients presented to our institution with a retropharyngeal abscess ranging from 10 months to 7 years after undergoing anterior cervical discectomy and fusion. All patients received at least a 6-week course of appropriate intravenous antibiotics. Only one patient had their initial ACDF instrumentation removed at the time of presentation for the abscess. Four out of the 7 patients were treated with irrigation and debridement in addition to intravenous antibiotics, whereas 3 patients were treated with no surgery and intravenous antibiotics alone. All patients were asymptomatic at final follow up.

CONCLUSIONS

Late retropharyngeal abscess after anterior cervical discectomy and fusion is a rare complication. Surgical management should be considered along with long term antibiotics. Removal of implants may not be necessary for infection resolution. Antibiotic treatment alone may be indicated for patients who are not septic, do not have airway compromise, or and can be considered for poor surgical candidates.

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.

Patients with Dual Shoulder-Spine Disease: Does Operative Order Affect Clinical Outcomes?

OBJECTIVE

1) To analyze the effect of operative sequence (anterior cervical discectomy and fusion [ACDF] first or rotator cuff repair [RCR] first) on surgical outcomes after both procedures for patients with dual shoulder-spine injuries and 2) to determine how operative sequence affects patient-reported outcome measures (PROMs) after surgery.

METHODS

Patients >18 years of age who underwent primary ACDF and primary RCR at our institution were retrospectively identified. Only patients with overlapping symptoms before the first procedure were included. Patients were divided into 2 cohorts (ACDF first or RCR first). Patient demographics, surgical characteristics, surgical outcomes, and PROMs were compared between groups. Multivariate linear regression models were developed to determine if operative order was predictive of improvements in PROM scores at the 1-year postoperative point after the second procedure. Alpha was set at P < 0.05.

RESULTS

Of the 85 patients included, 44 patients (51.8%) underwent ACDF first, whereas 41 patients (48.2%) underwent RCR first. There were no significant differences in the rate of 90-day readmission, spine reoperations, and rotator cuff reoperations between groups (all, P > 0.05). Multivariate linear regression showed that undergoing an ACDF first was not a significant predictor of Δ Mental Component Score of the Short-Form 12 (β = -2.78; P = 0.626) and Δ Physical Component Score of the Short-Form 12 (β = 7.74; P = 0.077) at the 1-year postoperative point after the second procedure.

CONCLUSIONS

For patients with dual shoulder-spine injuries who are appropriate surgical candidates, undergoing ACDF first compared with RCR first does not result in significant differences in clinical surgical or patient-reported outcomes.

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.

Assessment of Postoperative Outcomes of Spine Fusion Patients With History of Cardiac Disease

INTRODUCTION

There is paucity on the effect of different cardiac diagnoses on outcomes in elective spine fusion patients.

METHODS

Patients undergoing elective spine fusion surgery were isolated in the PearlDiver database. Patients were stratified by having a previous history of coronary artery disease (CAD), congestive heart failure (CHF), valve disorder (valve), dysrhythmia, and no heart disease (control). Means comparison tests (chi-squared and independent samples t-tests, as appropriate) compared differences in demographics, diagnoses, comorbidities, procedural characteristics, length of stay, complication outcomes, and total hospital charges among the cohort.

RESULTS

In total, 537,252 elective spine fusion patients were stratified into five groups: CAD, CHF, valve, dysrhythmia, and control. Among the cohort, patients with CHF had significantly higher rates of morbid obesity, peripheral vascular disease, and chronic kidney disease (P < 0.001 for all). Patients with CAD had significantly higher rates of chronic obstructive pulmonary disease, diabetes, hypertension, and hyperlipidemia (all P < 0.001). Comparing postoperative outcomes for CAD and control subjects, CAD was associated with higher odds of myocardial infarction (odds ratio [OR]: 1.64 [1.27 to 2.11]) (P < 0.05). Assessing postoperative outcomes for CHF versus control subjects, patients with CHF had higher rates of pneumonia, cerebrovascular accident (CVA), myocardial infarction, sepsis, and death (P < 0.001). Compared with control subjects, CHF was a significant predictor of death in spine fusion patients (OR: 2.0 [1.1 to 3.5], P = 0.022). Patients with valve disorder compared with control displayed significantly higher rates of 30-day readmission (P < 0.05) and 1.38× greater odds of CVA by 90 days postoperatively (OR: 1.4 [1.1 to 1.7], P = 0.007). Patients with dysrhythmia were associated with significantly higher odds of CVA (OR: 1.8 [1.4 to 2.3], P < 0.001) by 30 days postoperatively.

CONCLUSION

Heart disease presents an additional challenge to spine fusion patients who are undergoing a challenging and risky procedure. Before surgical intervention, a proper understanding of cardiac diagnoses could give insight into the potential risks for each patient based on their heart condition and preventive measures showing benefit in minimizing perioperative complications after elective spine fusion.

Establishing a Reference Procedure Length for Anterior Cervical Fusions: The Role for Standards in Surgical Process Improvement

Surgical process improvement strategies are increasingly being applied to specific procedures to improve value. A critical step in any process improvement strategy is the identification of performance benchmarks. Procedure length is a performance benchmark for anterior cervical discectomy and fusion (ACDF) procedures; therefore, we sought to establish reference procedure lengths for 1-level, 2-level, and 3-level ACDFs at both teaching and non-teaching institutions and to describe methods for using this information to advance surgical process improvement initiatives. We performed a retrospective analysis of consecutive ACDFs performed at a resident teaching institution (RT) and a non-teaching institution (NT) for all 1-level, 2-level, and 3-level ACDFs. Mean case lengths and patient outcomes were calculated for individual surgeons and institutions. After limiting cases to 1-level, 2-level, and 3-level ACDFs and applying all exclusion criteria, 991 cases at the RT institution and 131 cases at the NT institution (a total of 1122 cases) were available for analysis. The mean (SD) procedure length for 1-level, 2-level, and 3-level ACDFs at the RT versus NT institutions were 121.9 min (36.3 min) and 73.6 min (29.7 min) (p<0.001), 172.7 min (44.8 min) and 112.0 min (43.0 min) (p<0.001), and 218.3 min (54.9 min) and 167.6 min (54.2 min) (p<0.001), respectively. Thirty-day outcomes were the same between institutions, except that the RT institution had a shorter mean hospital length of stay for 2-level ACDFs (1.6 days versus 2.9 days, p=0.001). This study is the first to attempt to establish a standard reference procedure length for 1-level, 2-level, and 3-level ACDFs. These data can guide efforts in surgical process improvement.

IDENTIFICATION OF RISK FACTORS ASSOCIATED WITH 30-DAY READMISSION OF PATIENTS SUBMITTED TO ANTERIOR OR POSTERIOR ACCESS CERVICAL SPINE SURGERY

ABSTRACT Aim: To conduct a systematic review of the literature to identify risk factors associated with 30-day readmission of patients submitted to anterior or posterior access cervical spine surgery. Methods: The databases used to select the papers were PubMed, Web of Science, and Cochrane, using the following search strategy: patient AND readmission AND (30 day OR “thirty day” OR 30-day OR thirty-day) AND (spine AND cervical). Results: Initially, 179 papers that satisfied the established search stringwere selected. After reading the titles and abstracts, 46 were excluded from the sample for not effectively discussing the theme proposed for this review. Of the 133 remaining papers, 109 were also excluded after a detailed reading of their content, leaving 24 that were included in the sample for the meta-analysis. Conclusions: The average readmission rate in the studies evaluated was 4.85%. Only the occurrence of infections, as well as the presence of patients classified by the American Society of Anesthesiology (ASA) assessment system with scores greater than III, were causal factors that influenced the readmission of patients. No significant differences were noted when comparing the anterior and posterior surgical access routes. Level of evidence II; Systematic Review of Level II or Level I Studies with discrepant results.

Readmissions after elective orthopedic surgery in a comprehensive co-management care system-a retrospective analysis

Background

No surgical intervention is without risk. Readmissions and reoperations after elective orthopedic surgery are common and are also stressful for the patient. It has been shown that a comprehensive ortho-medical co-management model decreases readmission rates in older patients suffering from hip fracture; but it is still unclear if this also applies to elective orthopedic surgery. The aim of the current study was to determine the proportion of unplanned readmissions or returns to operating room (for any reason) across a broad elective orthopedic population within 90 days after elective surgery. All cases took place in a tertiary care center using co-management care and were also assessed for risk factors leading to readmission or unplanned return to operating room (UROR).

Methods

In this observational study, 1295 patients undergoing elective orthopedic surgery between 2015 and 2017 at a tertiary care center in Switzerland were investigated. The proportion of reoperations and readmissions within 90 days was measured, and possible risk factors for reoperation or readmission were identified using logistic regression.

Results

In our cohort, 3.2% (42 of 1295 patients) had an UROR or readmission. Sixteen patients were readmitted without requiring further surgery—nine of which due to medical and seven to surgical reasons. Patient-related factors associated with UROR and readmission were older age (67 vs. 60 years; p = 0.014), and American Society of Anesthesiologists physical status (ASA PS) score ≥ 3 (43% vs. 18%; p < 0.001). Surgery-related factors were: implantation of foreign material (62% vs. 33%; p < 0.001), duration of operation (76 min. vs. 60 min; p < 0.001), and spine surgery (57% vs. 17%; p < 0.001). Notably, only spine surgery was also found to be independent risk factor.

Conclusion

Rates of UROR during initial hospitalization and readmission were lower in the current study than described in the literature. However, several comorbidities and surgery-related risk factors were found to be associated with these events. Although no surgery is without risk, known threats should be reduced and every effort undertaken to minimize complications in high-risk populations. Further prospective controlled research is needed to investigate the potential benefits of a co-management model in elective orthopedic surgery.

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.

Ninety-Day Readmission After Open Surgical Repair of Stanford Type A Aortic Dissection

BACKGROUND

Investigations into readmissions after surgical repair of acute Stanford Type A aortic dissection (TAAD) remain scarce. We analyzed potential risk factors for readmission after TAAD.

METHODS

The 2013-2014 United States Nationwide Readmissions Database was queried for TAAD index hospitalizations and 90-day readmissions indicated by diagnostic and procedural codes. Multivariable analysis was completed to identify risk factors and the most common reasons for readmission.

RESULTS

We identified 6,975 patients (65% male; age, 60.0±0.4 years) who underwent surgical repair for TAAD. Overall, 2,062 patients (29.6%) were readmitted within 90 days: 634 (30.7%) during the first 30 days, and 1,428 (69.3%) during days 31-90. Readmitted patients had a higher prevalence of chronic kidney disease at index admission (18.0% vs 11.6%, P=.002), greater overall index length of stay (17.8±0.6 vs 15.5±0.4 days; P=.0003), and greater index hospitalization cost ($90,637±$2,691 vs $80,082±$2,091; P=.0003). Mortality during readmission was 3.6% (n=74). Indications for readmission were most commonly cardiac (26.2%), infectious (17.8%), and pulmonary (11.7%). Multivariable analysis identified 2 independent risk factors for readmission: acute kidney injury (OR 1.49; 95% CI 1.24-1.78, P<.0001) and an Elixhauser Comorbidity Index >4 (OR 1.26; 95% CI 1.06-1.49, P=.009).

CONCLUSIONS

After surgical repair of TAAD, approximately 30% of patients were readmitted within 90 days, two thirds of them during the 31- to 90-day period. Targeted improvements in perioperative care and post-discharge follow-up of patients with multiple comorbidities could mitigate readmission rates. Efforts to reduce readmissions should be continued throughout the 90-day period.

Hospital use following anterior cervical discectomy and fusion

Most existing anterior cervical discectomy and fusion (ACDF) outcome studies omit emergency department (ED) use. To our knowledge, this study on ED use following ACDF surgery is the first to use a direct patient chart review and the first to include revision patients, 1-5 levels of ACDFs, and performance of corpectomy in the analysis. This study examines the frequency and basis of hospital service use within 30 days of ACDF surgery, specifically ED visits, hospital readmissions, and returns to the operating room. A retrospective chart review was performed for 1273 consecutive patients who underwent ACDF surgery at one institution from July 2013 to June 2016. Of the 1273 patients with ACDF, 97 (7.6%) presented to the ED within 30 days after surgery. Of 43 patients with revision ACDF, 9 (20.9%) returned to the ED, compared with 88 (7.2%) of 1230 patients with primary ACDF (P = 0.001). Of the 111 ED visits by 97 patients, 40 (36%) were for cervicalgia, 13 (12%) were for dysphagia, 8 (7%) were for trauma, 7 (6%) were for nausea, 4 (4%) were for medication refill, 3 (3%) were for dehiscence, 3 (3%) were for pneumonia, and 3 (3%) were for urinary tract infection. Of the ED presentations, 8 (7%) occurred during the first 2 days after surgery, and 46 (41%) occurred within the first postoperative week.

Risk Factors Associated with 90-Day Readmissions Following Occipitocervical Fusion-A Nationwide Readmissions Database Study

BACKGROUND

Occipitocervical fusion (OCF) procedures are increasing due to an aging population and the prevalence of trauma, rheumatoid arthritis, and tumors. Reoperation rates and readmission risk factors for cervical fusions have been established, but in relation to OCF they have not been explored. This study investigates the patterns of readmissions and complications following OCF using a national database.

METHODS

The 2016 U.S. Nationwide Readmissions Database was used for sample collection. Adults (>18 years) who underwent OCF were identified using the 2016 ICD-10 coding system, and we examined the readmission rates (30-day and 90-day) and reoperation rates.

RESULTS

Between January and September 2016, a total of 477 patients underwent OCF; the 30-day and 90-day readmission rates were 10.4% and 22.4%, respectively. The 90-day reoperation rate related to the index surgery was 5.7%. Mean age (68.58 years) was significantly greater in the readmitted group versus nonreadmitted group (61.76 years) (P < 0.001). The readmitted group had a significantly higher Charlson Comorbidity Index and Elixhauser Comorbidity Index (5.00 and 2.41, respectively) than the nonreadmitted group (3.25 and 1.15, respectively; P < 0.001). Nonelective OCF showed a higher readmission rate (29.18%) versus elective OCF (12.23%) (P < 0.001). Medicare and Medicaid patients showed the highest rates of readmission (27.27% and 20.41%, respectively). Readmitted patients had higher total health care costs.

CONCLUSIONS

Nonelective OCF was found to have a readmission rate of almost 2½× that of elective OCF. Understanding risk factors associated with OCF will help with operative planning and patient optimization.

Institutional databases may underestimate the risk factors for 30-day unplanned readmissions compared to national databases

OBJECTIVE

The National Surgical Quality Improvement Program (NSQIP) and National Readmissions Database (NRD) are two widely used databases for research studies. However, they may not provide generalizable information in regard to individual institutions. Therefore, the objective of the present study was to evaluate 30-day readmissions following anterior cervical discectomy and fusion (ACDF) and posterior lumbar fusion (PLF) procedures by using these two national databases and an institutional cohort.

METHODS

The NSQIP and NRD were queried for patients undergoing elective ACDF and PLF, with the addition of an institutional cohort. The outcome of interest was 30-day readmissions following ACDF and PLF, which were unplanned and related to the index procedure. Subsequently, univariable and multivariable analyses were conducted to determine the predictors of 30-day readmissions by using both databases and the institutional cohort.

RESULTS

Among all identified risk factors, only hypertension was found to be a common risk factor between NRD and the institutional cohort following ACDF. NSQIP and the institutional cohort both showed length of hospital stay to be a significant predictor for 30-day related readmission following PLF. There were no overlapping variables among all 3 cohorts for either ACDF or PLF. Additionally, the national databases identified a greater number of risk factors for 30-day related readmissions than did the institutional cohort for both procedures.

CONCLUSIONS

Overall, significant differences were seen among all 3 cohorts with regard to top predictors of 30-day unplanned readmissions following ACDF and PLF. The higher quantity of significant predictors found in the national databases may suggest that looking at single-institution series for such analyses may result in underestimation of important variables affecting patient outcomes, and that big data may be helpful in addressing this concern.

Readmission in elective spine surgery: Will short stays be beneficial to patients

There has been limited discussion as to whether spine surgery patients are benefiting from shorter in-patient hospital stays or if they are incurring higher rates of readmission and complications secondary to shortened length of stays. Included in this study were 237,446 spine patients >18yrs and excluding infection. Patients with Clavien Grade 5 complications in 2015 had the lowest mean time to readmission after initial surgery in all years at 12.44 ± 9.03 days. Pearson bivariate correlations between LOS ≤ 1 day and decreasing days to readmission was the strongest in 2016.). Logistic regression analysis found that LOS ≤ 1 day showed an overall increase in the odds of hospital readmission from 2012 to 2016 (2.29 [2.00-2.63], 2.33 [2.08-2.61], 2.35 [2.11-2.61], 2.27 [2.06-2.49], 2.33 [2.14-2.54], all p < 0.001).

PEEK interbody devices for multilevel anterior cervical discectomy and fusion: association with more than 6-fold higher rates of pseudarthrosis compared to structural allograft

OBJECTIVE

Common interbody graft options for anterior cervical discectomy and fusion (ACDF) include allograft and polyetheretherketone (PEEK). PEEK has gained popularity due to its radiolucent properties and a modulus of elasticity similar to that of bone. PEEK devices also result in higher billing costs than allograft, which may drive selection. A previous study found a 5-fold higher rate of pseudarthrosis with the use of PEEK devices compared with structural allograft in single-level ACDF. Here the authors report on the occurrence of pseudarthrosis with PEEK devices versus structural allograft in patients who underwent multilevel ACDF.

METHODS

The authors retrospectively reviewed 81 consecutive patients who underwent a multilevel ACDF and had radiographic follow-up for at least 1 year. Data were collected on age, sex, BMI, tobacco use, pseudarthrosis, and rate of reoperation for pseudarthrosis. Logistic regression was used for data analysis.

RESULTS

Of 81 patients, 35 had PEEK implants and 46 had structural allograft. There were no significant differences between age, sex, smoking status, or BMI in the 2 groups. There were 26/35 (74%) patients with PEEK implants who demonstrated radiographic evidence of pseudarthrosis, compared with 5/46 (11%) patients with structural allograft (p < 0.001, OR 22.2). Five patients (14%) with PEEK implants required reoperation for pseudarthrosis, compared with 0 patients with allograft (p = 0.013).

CONCLUSIONS

This study reinforces previous findings on 1-level ACDF outcomes and suggests that the use of PEEK in multilevel ACDF results in statistically significantly higher rates of radiographic pseudarthrosis and need for revision surgery than allograft. Surgeons should consider these findings when determining graft options, and reimbursement policies should reflect these discrepancies.

Physician characteristics correlate with hospital readmission rates

Hospital readmission rates are used as a metric to measure quality patient care. While several tools predict readmissions based on patient-specific characteristics, this study assesses if physician characteristics correlate with hospital readmission rates.In a 5-year retrospective electronic record review at a single institution, 31 internal medicine attending physicians' discharges were tracked for a total of 70 physician years, and 15,933 hospital discharges. Each physician's yearly 7-day, 8 to 30-day, and 30-day readmission rates were compared. Each rate was also correlated with years of post-graduate clinical experience, discharge volume, physician sex, and fiscal year.Individual physicians had significantly different 7-day, 8 to 30-day, and 30-day readmission rates from each other. The rates were not related to sex, years after post-graduate training, or fiscal year. However, physician patient volume correlated with 7-day readmission rates. Physicians who discharged ≤100 patients per year had a higher 7-day readmission rate than physicians who discharged >100 patients per year. This correlation with patient volume did not hold for the 8 to 30-day and 30-day readmission rates.Individual physicians differ in their patient readmission rates in 7-day, 8 to 30-day, and 30-day categories. A critical level of a physician's hospital activity, as reflected by the number of patient discharges per year (>100), results in lower 7-day readmission rates. Sex, post-graduate years of clinical experience, and fiscal year did not play a role. The lack of correlation between each physicians' 7-day and 8 to 30-day readmission rates suggests that different physician factors are involved in these 2 rates.

Complications of anterior cervical spine surgery: a systematic review of the literature

The anterior approach to the cervical spine is commonly utilized for a variety of degenerative, traumatic, neoplastic, and infectious indications. While many potential complications overlap with those of the posterior approach, the distinct anatomy of the anterior neck also presents a unique set of hazards. We performed a systematic review of the literature to assess the etiology, presentation, natural history, and management of these complications. Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a PubMed search was conducted to evaluate clinical studies and case reports of patients who suffered a complication of anterior cervical spine surgery. The search specifically included articles concerning adult human subjects, written in the English language, and published from 1989 to 2019. The PubMed search yielded 240 articles meeting our criteria. The overall rates of complications were as follows: dysphagia 5.3%, esophageal perforation 0.2%, recurrent laryngeal nerve palsy 1.3%, infection 1.2%, adjacent segment disease 8.1%, pseudarthrosis 2.0%, graft or hardware failure 2.1%, cerebrospinal fluid leak 0.5%, hematoma 1.0%, Horner syndrome 0.4%, C5 palsy 3.0%, vertebral artery injury 0.4%, and new or worsening neurological deficit 0.5%. Morbidity rates in anterior cervical spine surgery are low. Nevertheless, the unique anatomy of the anterior neck presents a wide variety of potential complications involving vascular, aerodigestive, neural, and osseous structures.

Using machine learning to predict 30-day readmissions after posterior lumbar fusion: an NSQIP study involving 23,264 patients

OBJECTIVE

Unplanned preventable hospital readmissions within 30 days are a great burden to patients and the healthcare system. With an estimated $41.3 billion spent yearly, reducing such readmission rates is of the utmost importance. With the widespread adoption of big data and machine learning, clinicians can use these analytical tools to understand these complex relationships and find predictive factors that can be generalized to future patients. The object of this study was to assess the efficacy of a machine learning algorithm in the prediction of 30-day hospital readmission after posterior spinal fusion surgery.

METHODS

The authors analyzed the distribution of National Surgical Quality Improvement Program (NSQIP) posterior lumbar fusions from 2011 to 2016 by using machine learning techniques to create a model predictive of hospital readmissions. A deep neural network was trained using 177 unique input variables. The model was trained and tested using cross-validation, in which the data were randomly partitioned into training (n = 17,448 [75%]) and testing (n = 5816 [25%]) data sets. In training, the 17,448 training cases were fed through a series of 7 layers, each with varying degrees of forward and backward communicating nodes (neurons).

RESULTS

Mean and median positive predictive values were 78.5% and 78.0%, respectively. Mean and median negative predictive values were both 97%, respectively. Mean and median areas under the curve for the model were 0.812 and 0.810, respectively. The five most heavily weighted inputs were (in order of importance) return to the operating room, septic shock, superficial surgical site infection, sepsis, and being on a ventilator for > 48 hours.

CONCLUSIONS

Machine learning and artificial intelligence are powerful tools with the ability to improve understanding of predictive metrics in clinical spine surgery. The authors' model was able to predict those patients who would not require readmission. Similarly, the majority of predicted readmissions (up to 60%) were predicted by the model while retaining a 0% false-positive rate. Such findings suggest a possible need for reevaluation of the current Hospital Readmissions Reduction Program penalties in spine surgery.

Comparative and Predictor Analysis of 30-day Readmission, Reoperation, and Morbidity in Patients Undergoing Multilevel ACDF Versus Single and Multilevel ACCF Using the ACS-NSQIP Dataset

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to determine the differences in 30-day readmission, reoperation, and morbidity for patients undergoing multilevel anterior cervical discectomy and fusion (ACDF) or single and multilevel anterior cervical corpectomy and fusion (ACCF).

SUMMARY OF BACKGROUND DATA

Despite increasing rates of surgical treatment of cervical spine disease, few studies have compared outcomes by surgical technique. To the best of our knowledge, this is the only large-scale administrative database study that directly evaluates early outcomes between multilevel ACDF and single and multilevel ACCF.

METHODS

Patients who underwent ACDF and ACCF were identified using the NSQIP database. Multivariate regression was utilized to compare rates of readmission, reoperation, morbidity, and specific complications between surgical techniques, and to evaluate for predictors of primary outcomes.

RESULTS

We identified 15,600 patients. ACCF independently predicted (P < 0.001) greater reoperation (odds ratio [OR] = 1.876) and morbidity (OR = 1.700), but not readmission, on multivariate analysis. ACCF was also associated with greater rates of transfusion (OR = 3.273, P < 0.001) and DVT/thrombophlebitis (OR = 2.852, P = 0.001). ACCF had significantly (P < 0.001) greater operative time and length of stay. In the cohort, increasing age (P < 0.001), diabetes (P = 0.025), chronic obstructive pulmonary disease (P = 0.027), disseminated cancer (P = 0.009), and American Society of Anesthesiologists (ASA) class ≥3 (P < 0.001) predicted readmission. Age (P = 0.011), female sex (P = 0.001), heart failure (P = 0.002), ASA class ≥3 (P < 0.001), and increased creatinine (P = 0.044), white cell count (P = 0.033), and length of stay (P < 0.001) predicted reoperation. Age (P < 0.001), female sex (P = 0.002), disseminated cancer (P = 0.010), ASA class ≥3 (P < 0.001), increased white cell count (P = 0.036) and length of stay (P < 0.001), and decreased hematocrit (P < 0.001) predicted morbidity. Within ACDF, three or more levels treated compared to two levels did not predict poorer 30-day outcomes.

CONCLUSION

Compared to multilevel ACDF, ACCF was associated with an 88% increased odds of reoperation and 70% increased odds of morbidity; readmission was similar between techniques. Older age, higher ASA class, and specific comorbidities predicted poorer 30-day outcomes. These findings can guide surgical solution given specific factors.

LEVEL OF EVIDENCE

3.

Predicting In-Hospital Complications After Anterior Cervical Discectomy and Fusion: A Comparison of the Elixhauser and Charlson Comorbidity Indices

OBJECTIVE

The objective of this study was to determine the ability of the Elixhauser Comorbidity Index (ECI) and Charlson Comorbidity Index (CCI) to predict postoperative complications after anterior cervical discectomy and fusion (ACDF).

METHODS

This was a retrospective study of ACDF hospitalizations in the National Inpatient Sample from 2013 to 2014. The ECI and CCI were calculated, and patients who experienced postoperative complications were identified. The ability of these indexes to predict complications was compared using the c statistic (area under the receiver operating characteristic curve [AUC]). In addition, the CCI and ECI were compared with a base model that included age, sex, race, and primary payer.

RESULTS

A total of 261,780 patients were included. Patients who experienced a complication were more often male (P < 0.0001) and older (P < 0.0001). They also had a higher comorbidity burden as assessed by both the ECI (P < 0.0001) and the CCI (P < 0.0001). The ECI was superior in predicting airway complications (AUC, 0.81 vs. 0.75; P < 0.0001), hemorrhagic anemia (AUC, 0.67 vs. 0.63; P = 0.0015), pulmonary embolism (AUC, 0.91 vs. 0.77; P < 0.0001), wound dehiscence (AUC, 0.80 vs. 0.55; P = 0.0080), sepsis (AUC, 0.87 vs. 0.82; P = 0.0001), and septic shock (AUC, 0.94 vs. 0.83; P < 0.0001). The CCI was not found to be superior to the ECI for predicting any complications. Both were excellent for predicting mortality (ECI AUC, 0.87; CCI AUC, 0.90).

CONCLUSIONS

The ECI was superior to the CCI in predicting 6 of 15 complications in this study. Both are excellent tools for predicting mortality after ACDF.

Late deep cervical infection after anterior cervical discectomy and fusion: a case report and literature review

Background

Anterior cervical discectomy and fusion (ACDF) is often performed for the treatment of degenerative cervical spine. While this procedure is highly successful, 0.1–1.6% of early and late postoperative infection have been reported although the rate of late infection is very low.

Case presentation

Here, we report a case of 59-year-old male patient who developed deep cervical abscess 30 days after anterior cervical discectomy and titanium cage bone graft fusion (autologous bone) at C3/4 and C4/5. The patient did not have esophageal perforation. The abscess was managed through radical neck dissection approach with repated washing and removal of the titanium implant. Staphylococcus aureus was positively cultured from the abscess drainage, for which appropriate antibiotics including cefoxitin, vancomycin, levofloxacin, and cefoperazone were administered postoperatively. In addition, an external Hallo frame was used to support unstable cervical spine. The patient’s deep cervical infection was healed 3 months after debridement and antibiotic administration. His cervial spine was stablized 11 months after the surgery with support of external Hallo Frame.

Conclusions

This case suggested that deep cervical infection should be considered if a patient had history of ACDF even in the absence of esophageal perforation.

A Review of Complication Rates for Anterior Cervical Diskectomy and Fusion (ACDF)

Background:

There are multiple complications reported for anterior cervical diskectomy and fusion (ACDF), one of the most common cervical spine operations performed in the US (e.g. estimated at 137,000 ACDF/year).

Methods:

Multiple studies analyzed the risks and complications rates attributed to ACDF.

Results:

In multiple studies, overall morbidity rates for ACDF varied from 13.2% to 19.3%. These included in descending order; dysphagia (1.7%-9.5%), postoperative hematoma (0.4%-5.6% (surgery required in 2.4% of 5.6%), with epidural hematoma 0.9%), exacerbation of myelopathy (0.2%-3.3%), symptomatic recurrent laryngeal nerve palsy (0.9%-3.1%), cerebrospinal fluid (CSF) leak (0.5%-1.7%), wound infection (0.1-0.9%-1.6%), increased radiculopathy (1.3%), Horner’s syndrome (0.06%-1.1%), respiratory insufficiency (1.1%), esophageal perforation (0.3%-0.9%, with a mortality rate of 0.1%), and instrument failure (0.1%-0.9%). There were just single case reports of an internal jugular veing occlusion and a phrenic nerve injury. Pseudarthrosis occurred in ACDF and was dependant on the number of levels fused; 0-4.3% (1-level), 24% (2-level), 42% (3 level) to 56% (4 levels). The reoperation rate for symptomatic pseudarthrosis was 11.1%. Readmission rates for ACDF ranged from 5.1% (30 days) to 7.7% (90 days postoperatively).

Conclusions:

Complications attributed to ACDF included; dysphagia, hematoma, worsening myelopathy, recurrent laryngeal nerve palsy, CSF leaks, wound infection, radiculopathy, Horner’s Syndrome, respiratory insufficiency, esophageal perforation, and instrument failure. There were just single case reports of an internal jugular vein thrombosis, and a phrenic nerve injury. As anticipated, pseudarthrosis rates increased with the number of ACDF levels, ranging from 0-4.3% for 1 level up to 56% for 4 level fusions.