Total Disc Arthroplasty Versus Anterior Interbody Fusion in the Lumbar Spine Have Relatively a Few Differences in Readmission and Short-term Adverse Events

Prognostic Factors for Outcome of Fusion Surgery in Patients With Chronic Low Back Pain - A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVE

This systematic review aims to identify prognostic factors, encompassing biomedical and psychosocial variables, linked to outcome of fusion surgery for chronic low back pain (CLBP) in single or two-level lumbar degenerative spinal disorders. Identifying these factors is crucial for decision making and therefore long-term treatment outcome.

METHODS

A systematic search (PROSPERO ID: CRD4202018927) from January 2010 to October 2022 was conducted, utilizing Medline, Embase, and the Cochrane Database of Systematic Reviews (CDSR, CENTRAL). Prognostic factors associated with various outcomes, including functional status, back and leg pain, health-related quality of life, complications, return to work, and analgesic use, were assessed. Risk of bias was determined using QUIPS, and the quality of evidence was evaluated using GRADE approach.

RESULTS

Of the 9852 initially screened studies, eleven studies (n = 16,482) were included in the analysis. In total, 161 associations were identified, with 67 prognostic factors showing statistical significance (P < 0.05). Thirty associations were supported by two or more studies, and only eight associations were eligible for meta-analyses: female gender remained statistically significant associated with decreased postoperative back pain, but negatively associated with complication rates and functional status, and smoking with increased postoperative back pain.

CONCLUSION

Only female gender and smoking were consistently associated with outcome of fusion for CLBP. Most of the included studies exhibited low to moderate methodological quality, which may explain the relatively weak associations identified for the assessed prognostic factors.

Lumbar Disc Replacement Versus Interbody Fusion: Meta-analysis of Complications and Clinical Outcomes

Background

Lumbar spinal fusion is a commonly performed operation with relatively high complication and revision surgery rates. Lumbar disc replacement is less commonly performed but may have some benefits over spinal fusion. This meta-analysis aims to compare the outcomes of lumbar disc replacement (LDR) versus interbody fusion (IBF), assessing their comparative safety and effectiveness in treating lumbar DDD.

Methods

PubMed, Cochrane, and Google Scholar (pages 1-2) were searched up until February 2024. The studied outcomes included operative room (OR) time, estimated blood loss (EBL), length of hospital stay (LOS), complications, reoperations, Oswestry Disability Index (ODI), back pain, and leg pain.

Results

Ten studies were included in this meta-analysis, of which six were randomized controlled trials, three were retrospective studies, and one was a prospective study. A total of 1720 patients were included, with 1034 undergoing LDR and 686 undergoing IBF. No statistically significant differences were observed in OR time, EBL, or LOS between the LDR and IBF groups. The analysis also showed no significant differences in the rates of complications, reoperations, and leg pain between the two groups. However, the LDR group demonstrated a statistically significant reduction in mean back pain (p=0.04) compared to the IBF group.

Conclusion

Both LDR and IBF procedures offer similar results in managing CLBP, considering OR time, EBL, LOS, complication rates, reoperations, and leg pain, with slight superiority of back pain improvement in LDR. This study supports the use of both procedures in managing degenerative spinal disease.

Analysis of the Frequency of Intraoperative Complications in Anterior Lumbar Interbody Fusion: A Systematic Review

OBJECTIVE

We assessed the frequency of intraoperative complication rates related to access surgery, operating time, and intraoperative bleeding rates described in the literature for patients undergoing anterior lumbar interbody fusion (ALIF) to evaluate the adverse effects and, thus, help in therapeutic decision making and contribute to future clinical trials.

METHODS

A systematic review was conducted of MEDLINE and Embase databases in March 2023. The main inclusion criteria were adult patients aged >18 years, with no maximum age limit; the use of ALIF; the presence of quantitative data on intraoperative complications; and randomized controlled trials and cohort studies. Vascular and peritoneal injuries were considered primary endpoints. The operative time and intraoperative bleeding rate were secondary endpoints. Reports and case series, case-control series, systematic reviews, and meta-analyses were excluded.

RESULTS

Eight studies were included with a total of 2395 patients. We found important quantitative data for future randomized clinical studies involving ALIF surgery, including the rate of vascular lesions (2.79%) and peritoneal lesions (0.37%). In addition to these factors, only 4 of the 8 studies addressed the average surgery time, with a total average of 145.61 minutes. Furthermore, 6 of the 8 articles reported the mean rate of intraoperative bleeding, with a total mean blood loss of 272.75 mL.

CONCLUSIONS

ALIF is a lumbar spine access technique with low intraoperative complications. Patients with contraindications have a higher risk of complications. Randomized clinical trials are needed to assess the efficacy and safety of the procedure.

Baseline Frailty and Discharge to Advanced Care Facilities in Patients Undergoing Lumbar Interbody Fusion for Lumbar Degenerative Disease: A Multicenter Registry Analysis of 7153 Patient Cases Comparing the Risk Analysis Index to the 5-Factor Modified Frailty Index

OBJECTIVE

To evaluate the impact of frailty, as measured by the 5-factor modified Frailty Index (mFI-5) and the Risk Analysis Index (RAI), on advanced care facility discharge (FD) in patients who underwent lumbar fusion for lumbar degenerative spine disease.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (2012-2020) was queried for adults (≥18 years) undergoing lumbar fusion for lumbar degenerative disease. Descriptive statistics and univariate crosstabulation were used to assess baseline demographics, preoperative comorbidities, and postoperative outcomes. Receiver operating characteristic curve analysis was used to assess the discriminative threshold of the mFI-5 and RAI on FD within this population.

RESULTS

The median patient age in this study cohort (N = 7153) was 56 years and FD occurred in 7.3% of cases. Receiver operating characteristic curve analysis demonstrated that both the mFI-5 and the RAI accurately predicted FD (C-statistics: mFI-5: 0.627; RAI: 0.746). DeLong's test found that the RAI had superior discrimination when compared to the mFI-5 (P < 0.0001).

CONCLUSIONS

RAI is a reliable predictor of FD in lumbar degenerative disease patients who underwent lumbar interbody fusion and demonstrated superior discrimination compared to the mFI-5. Identification of patients at risk for FD may facilitate more precise risk stratification to enable better preoperative decision-making and help set more realistic expectations of care.

Outcomes of patients undergoing single-level arthroplasty versus anterior lumbar interbody fusion

BACKGROUND

Compared to vertebral body fusion, artificial discs are thought to lessen the risks of adjacent segment disease and the need for additional surgery by maintaining spinal mobility as they mimic the intervertebral disc structure. No studies have compared the rates of postoperative complications and the requirement for secondary surgery at adjacent segments among patients who have undergone anterior lumbar interbody fusions (ALIF) versus those undergoing lumbar arthroplasty.

METHODS

An all-payer claims database identified 11,367 individuals who underwent single-level ALIF and lumbar arthroplasty for degenerative disc disease (DDD) between January 2010 and October 2020. Rates of complications following surgery, the need for additional lumbar surgeries, length of stay (LOS), and postoperative opioid utilization were assessed in matched cohorts based on logistic regression models. Kaplan-Meyer plots were created to model the probability of additional surgery.

RESULTS

Following 1:1 exact matching, 846 records of patients who had undergone ALIF or lumbar arthroplasty were analyzed. All-cause readmission within 30-30 days following surgery was significantly higher in patients undergoing ALIF versus arthroplasty (2.6% vs. 0.71%, p = 0.02). LOS was significantly lower among the patients who had undergone ALIF (1.043 ± 0.21 vs. 2.17 ± 1.7, p < .001).

CONCLUSIONS

ALIF and lumbar arthroplasty procedures are equally safe and effective in treating DDD. Our findings do not support that single-level fusions may biomechanically necessitate revisional surgeries.

Comparative Analysis of 30-Day Readmission, Reoperation, and Morbidity between Posterior Cervical Decompression and Fusion Performed in Inpatient and Outpatient Settings

STUDY DESIGN

A retrospective cohort study.

PURPOSE

To compare 30-day readmission, reoperation, and morbidity for patients undergoing posterior cervical decompression and fusion (PCDF) in inpatient vs. outpatient settings.

OVERVIEW OF LITERATURE

PCDF has recently been increasingly performed in outpatient settings, often utilizing minimally invasive techniques. However, literature evaluating short-term outcomes for PCDF is scarce. Moreover, no currently large-scale database studies have compared short-term outcomes between PCDF performed in the inpatient and outpatient settings.

METHODS

Patients who underwent PCDF from 2005 to 2018 were identified using the National Surgical Quality Improvement Program database. Regression analysis was utilized to compare primary outcomes between surgical settings and evaluate for predictors thereof.

RESULTS

We identified 8,912 patients. Unadjusted analysis revealed that outpatients had lower readmission (4.7% vs. 8.8%, p =0.020), reoperation (1.7% vs. 3.8%, p =0.038), and morbidity (4.5% vs. 11.2%, p <0.001) rates. After adjusting for baseline differences, readmission, reoperation, and morbidity no longer statistically differed between surgical settings. Outpatients had lower operative time (126 minutes vs. 179 minutes) and levels fused (1.8 vs. 2.2) (p <0.001). Multivariate analysis revealed that age (p =0.008; odds ratio [OR], 1.012), weight loss (p =0.045; OR, 2.444), and increased creatinine (p <0.001; OR, 2.233) independently predicted readmission. The American Society of Anesthesiologists (ASA) classification of ≥3 predicted reoperation (p =0.028; OR, 1.406). Rehabilitation discharge (p <0.001; OR, 1.412), ASA-class of ≥3 (p =0.008; OR, 1.296), decreased hematocrit (p <0.001; OR, 1.700), and operative time (p <0.001; OR, 1.005) predicted morbidity.

CONCLUSIONS

The 30-day outcomes were statistically similar between surgical settings, indicating that PCDF can be safely performed as an outpatient procedure. Surrogates for poor health predicted negative outcomes. These results are particularly important as we continue to shift spinal surgery to outpatient centers. This importance has been highlighted by the need to unburden inpatient sites, particularly during public health emergencies, such as the coronavirus disease 2019 pandemic.

Impact of Discharge to Rehabilitation on Postdischarge Morbidity Following Multilevel Posterior Lumbar Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to compare 30-day postdischarge morbidity for 3-or-more level (multilevel) posterior lumbar fusion in patients who were discharged to home versus rehabilitation.

SUMMARY OF BACKGROUND DATA

Spine surgery has been increasingly performed in the elderly population, with many of these patients being discharged to rehabilitation and skilled nursing facilities. However, research evaluating the safety of nonhome discharge following spine surgery is limited.

MATERIALS AND METHODS

Patients who underwent multilevel posterior lumbar fusion from 2005 to 2018 were identified using the National Surgical Quality Improvement Program (NSQIP) database. Regression was utilized to compare primary outcomes between discharge disposition and to evaluate for predictors thereof.

RESULTS

We identified 5276 patients. Unadjusted analysis revealed that patients who were discharged to rehabilitation had greater postdischarge morbidity (5.6% vs. 2.6%). After adjusting for baseline differences, discharge to rehabilitation no longer predicted postdischarge morbidity [odds ratio (OR)=1.409, confidence interval: 0.918-2.161, P=0.117]. Multivariate analysis also revealed that age (P=0.026, OR=1.023), disseminated cancer (P=0.037, OR=6.699), and readmission (P<0.001, OR=28.889) independently predicted postdischarge morbidity.

CONCLUSIONS

Thirty days morbidity was statistically similar between patients who were discharged to home and rehabilitation. With appropriate patient selection, discharge to rehabilitation can potentially minimize 30-day postdischarge morbidity for more medically frail patients undergoing multilevel posterior lumbar fusion. These results are particularly important given an aging population, with a great portion of elderly patients who may benefit from postacute care facility discharge following spine surgery.

Predictors of Extended Hospitalization and Early Reoperation After Elective Lumbar Disc Arthroplasty

BACKGROUND

Lumbar disc arthroplasty (LDA) has emerged as a motion-sparing alternative to lumbar fusion. Although LDA may be amenable to the ambulatory surgical setting, to date no study has identified the factors predisposing patients to extended hospital stay.

METHODS

A national surgical quality improvement database was queried from 2011 to 2019 for patients undergoing elective, single-level, primary LDA. Univariate and multivariate logistic regression analyses were performed to elucidate predictors of length of stay (LOS) at or above the 90th percentile of the study population (3 days). Secondary study endpoints included rates of complications, as well as predictors and reasons for unplanned reoperation within 30 days.

RESULTS

A total of 630 patients met eligibility criteria for the study, of whom 517 (82.1%) had LOS <3 days and 113 (17.9%) had LOS ≥3 days. Multivariate logistic regression revealed associations between prolonged hospitalization and postoperative diagnosis of degenerative disk disease, obesity, Hispanic identity, and operation length >120 minutes. Before discharge, patients with LOS ≥3 days were more likely to have venous thromboembolisms, pneumonia, surgical site infections, and reoperations. Independent predictors of reoperation were wound infections, diabetes, and smoking.

CONCLUSIONS

Complications following elective single-level LDA are relatively rare, with few extended hospitalizations being attributable to any specific complication. Risk factors for prolonged LOS appear to be related to diagnosis and surgical time rather than to modifiable preoperative comorbidities. Conversely, unplanned reoperations within 30 days are associated with optimizable perioperative factors such as smoking, diabetes, and surgical site infection.

Comparative Analysis of 30-Day Readmission, Reoperation, and Morbidity Between Lumbar Disc Arthroplasty Performed in the Inpatient and Outpatient Settings Utilizing the ACS-NSQIP Dataset

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Spine surgery has been increasingly performed in the outpatient setting, providing greater control over cost, efficiency, and resource utilization. However, research evaluating the safety of this trend is limited. The objective of this study is to compare 30-day readmission, reoperation, and morbidity for patients undergoing lumbar disc arthroplasty (LDA) in the inpatient versus outpatient settings.

METHODS

Patients who underwent LDA from 2005 to 2018 were identified using the ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database. Regression was utilized to compare readmission, reoperation, and morbidity between surgical settings, and to evaluate for predictors thereof.

RESULTS

We identified 751 patients. There were no significant differences between inpatient and outpatient LDA in rates of readmission, reoperation, or morbidity on univariate or multivariate analyses. There were also no significant differences in rates of specific complications. Inpatient operative time (138 ± 75 minutes) was significantly (P < .001) longer than outpatient operative time (106 ± 43 minutes). In multivariate analysis, diabetes (P < .001, OR = 7.365), baseline dyspnea (P = .039, OR = 6.447), and increased platelet count (P = .048, OR = 1.007) predicted readmission. Diabetes (P = .016, OR = 6.533) and baseline dyspnea (P = .046, OR = 13.814) predicted reoperation. Baseline dyspnea (P = .021, OR = 8.188) and ASA (American Society of Anesthesiologists) class ≥3 (P = .014, OR = 3.515) predicted morbidity. Decreased hematocrit (P = .008) and increased operative time (P = .003) were associated with morbidity in univariate analysis, but not in multivariate analysis.

CONCLUSIONS

Readmission, reoperation, and morbidity were statistically similar between surgical setting, indicating that LDA can be safely performed in the outpatient setting. Higher ASA class and specific comorbidities predicted poorer 30-day outcomes. These findings can guide choice of surgical setting given specific patient factors.

Artificial disc replacement in spine surgery

Total disc replacement (TDR) is an innovative procedure that has gained traction in spine surgery. A large amount of data in the literature report on the short-term outcomes of TDR surgery favorably. However, surgeons remain reluctant to opt for TDR surgery due to uncertainty of long-term outcomes. Recently, long term data regarding TDR surgery has become available, with some studies showing superior outcomes to fusion surgery. The goal of this review is to synthesize and clinically contextualize the recent literature on TDR surgery. This article also provides brief discussion of the biggest challenges currently facing disc arthroplasties and the ways in which they are being tackled.

Reporting Methodology of Neurosurgical Studies Utilizing the American College of Surgeons-National Surgical Quality Improvement Program Database: A Systematic Review and Critical Appraisal

BACKGROUND

Use of large databases such as the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) has become increasingly common in neurosurgical research.

OBJECTIVE

To perform a critical appraisal and evaluation of the methodological reporting for studies in neurosurgical literature that utilize the ACS-NSQIP database.

METHODS

We queried Ovid MEDLINE, EMBASE, and PubMed databases for all neurosurgical studies utilizing the ACS-NSQIP. We assessed each study according to number of criteria fulfilled with respect to Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement, REporting of studies Conducted using Observational Routinely-collected Health Data (RECORD) Statement, and Journal of American Medical Association–Surgical Section (JAMA-Surgery) Checklist. A separate analysis was conducted among papers published in core and noncore journals in neurosurgery according to Bradford's law.

RESULTS

A total of 117 studies were included. Median (interquartile range [IQR]) scores for number of fulfilled criteria for STROBE Statement, RECORD Statement, and JAMA-Surgery Checklist were 20 (IQR:19-21), 9 (IQR:8-9), and 6 (IQR:5-6), respectively. For STROBE Statement, RECORD Statement, and JAMA-Surgery Checklist, item 9 (potential sources of bias), item 13 (supplemental information), and item 9 (missing data/sensitivity analysis) had the highest number of studies with no fulfillment among all studies (56, 68, 50%), respectively. When comparing core journals vs noncore journals, no significant difference was found (STROBE, P = .94; RECORD, P = .24; JAMA-Surgery checklist, P = .60).

CONCLUSION

While we observed an overall satisfactory reporting of methodology, most studies lacked mention of potential sources of bias, data cleaning methods, supplemental information, and external validity. Given the pervasive role of national databases and registries for research and health care policy, the surgical community needs to ensure the credibility and quality of such studies that ultimately aim to improve the value of surgical care delivery to patients.

Cardiac Complications Related to Spine Surgery: Timing, Risk Factors, and Clinical Effect

INTRODUCTION

Large cohort studies evaluating cardiac complications in patients undergoing spine surgery are lacking. The purpose of this study was to determine the incidence, timing, risk factors, and effect of cardiac complications in spine surgery by using a national database, the American College of Surgeons National Surgical Quality Improvement Program.

METHODS

Patients who underwent spine surgery in the 2005 to 2012 National Surgical Quality Improvement Program database were identified. The primary outcome was an occurrence of cardiac arrest or myocardial infarction during the operation or the 30-day postoperative period. Risk factors for development of cardiac complications were identified using multivariate regression. The postoperative length of stay, 30-day readmission, and mortality were compared between patients who did and did not experience a cardiac complication.

RESULTS

A total of 30,339 patients who underwent spine surgery were identified. The incidence of cardiac complications was 0.34% (95% confidence interval [CI], 0.27% to 0.40%). Of the cases in which a cardiac complication developed, 30% were diagnosed after discharge. Risk factors for the development of cardiac complications were greater age (most notably ≥80 years, relative risk [RR] = 5.53; 95% CI = 2.28 to 13.43; P < 0.001), insulin-dependent diabetes (RR = 2.58; 95% CI = 1.51 to 4.41; P = 0.002), preoperative anemia (RR = 2.46; 95% CI = 1.62 to 3.76; P < 0.001), and history of cardiac disorders and treatments (RR = 1.88; 95% CI = 1.16 to 3.07; P = 0.011). Development of a cardiac complication before discharge was associated with a greater length of stay (7.9 versus 2.6 days; P < 0.001), and a cardiac complication after discharge was associated with increased 30-day readmission (RR = 12.32; 95% CI = 8.17 to 18.59; P < 0.001). Development of a cardiac complication any time during the operation or 30-day postoperative period was associated with increased mortality (RR = 113.83; 95% CI = 58.72 to 220.68; P < 0.001).

DISCUSSION

Perioperative cardiac complications were diagnosed in approximately 1 in 300 patients undergoing spine surgery. High-risk patients should be medically optimized and closely monitored through the perioperative period.

LEVEL OF EVIDENCE

Level III.

Incidence, Risk Factors, and Impact of Clostridium difficile Colitis After Spine Surgery: An Analysis of a National Database

STUDY DESIGN

A retrospective study of prospectively collected data.

OBJECTIVE

The aim of this study was to utilize a large national database with post-hospitalization follow-up data [National Surgical Quality Improvement Program (NSQIP)] to determine the incidence, risk factors, timing, and clinical impact of Clostridium difficile colitis in spine surgery patients.

SUMMARY OF BACKGROUND DATA

Recent literature has suggested an increased incidence of C. difficile infections. However, there has been a lack of large cohort studies defining the incidence and impact of C. difficile colitis in patients undergoing spine surgery.

METHODS

Patients who underwent spine surgical procedures in the 2015 NSQIP database were identified. The primary outcome was a diagnosis of C. difficile colitis within the 30-day postoperative period. Independent risk factors for development of C. difficile colitis were identified using multivariate regression. Postoperative length of stay and rate of 30-day readmission were compared between patients who did and did not develop C. difficile colitis.

RESULTS

A total of 23,981 patients who underwent spine surgical procedures were identified. The incidence of C. difficile colitis was approximately 0.11% [95% confidence interval (95% CI), 0.07-0.16]. Of the cases that developed C. difficile colitis, 70% were diagnosed postdischarge and 88% had not had a pre-existing infection diagnosed. Independent risk factors for the development of C. difficile colitis were combined anterior/posterior lumbar fusion procedures [odds ratio (OR) = 12.29, 95% CI = 2.22-68.13, P = 0.010], greater age (most notably ≥76 years old, OR = 10.31, 95% CI = 3.06-34.76, P < 0.001), hypoalbuminemia (OR = 6.40, 95% CI = 2.49-16.43, P < 0.001), and anemia (OR = 2.39, 95% CI = 1.13-5.05, P = 0.023). The development of C. difficile colitis was associated with greater length of stay (2.2 vs. 12.5 days; P < 0.001) and increased 30-day readmission (OR = 8.21, 95% CI = 3.14-21.45, P < 0.001).

CONCLUSION

C. difficile was diagnosed in 0.11% of patients undergoing spine surgery. The majority of these cases occurred after discharge and in patients not having prior infection diagnoses. High-risk patients should be monitored and targeted with preventative interventions accordingly.

LEVEL OF EVIDENCE

3.