External Validation of an Online Wound Infection and Wound Reoperation Risk Calculator After Metastatic Spinal Tumor Surgery

STUDY DESIGN

This was a single-institutional retrospective cohort study.

OBJECTIVE

Wound infections are common following spine metastasis surgery and can result in unplanned reoperations. A recent study published an online wound complication risk calculator but has not yet undergone external validation. Our aim was to evaluate the accuracy of this risk calculator in predicting 30-day wound infections and 30-day wound reoperations using our operative spine metastasis population.

METHODS

An internal operative database was used to identify patients between 2012 and 2022. The primary outcomes were 1) any surgical site infection and 2) wound-related revision surgery within 30 days following surgery. Patient details were manually collected from electronic medical records and entered into the calculator to determine predicted complication risk percentages. Predicted risks were compared to observed outcomes using receiver operator characteristic (ROC) curves with areas under the curve (AUC).

RESULTS

A total of 153 patients were included. The observed 30-day postoperative wound infection incidence was 5% while the predicted wound infection incidence was 6%. In ROC analysis, good discrimination was found for the wound infection model (AUC = 0.737; P = 0.024). The observed wound reoperation rate was 5% and the predicted wound reoperation rate was 6%. ROC analysis demonstrated poor discrimination for wound reoperations (AUC = 0.559; P = 0.597).

CONCLUSIONS

The online wound-related risk calculator was found to accurately predict wound infections but not wound reoperations within our metastatic spine surgery cohort. We suggest that the model may be clinically useful despite underlying population differences, but further work must be done to generate and validate accurate prediction tools.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The prognostic role of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and systemic immune-inflammation index on short- and long-term outcome following surgery for spinal metastases

OBJECTIVE

Inflammatory markers such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) have shown promise in predicting mortality in various types of cancer. The purpose of this study was to assess NLR, PLR, and SII in predicting 30-day mortality and overall survival (OS) among surgically treated patients with spinal metastasis.

METHODS

This was a retrospective study including 153 patients who underwent surgery for spinal metastasis between 2012 and 2022. Electronic medical records were manually reviewed, and NLR, PLR, and SII were calculated from preoperative neutrophil, platelet, and lymphocyte counts. Receiver operating characteristic curves with areas under the curve were generated to determine cutoff values. Logistic regression was used to determine the odds ratios (ORs) for 30-day mortality. The Kaplan-Meier method and Cox regression were used to determine the hazard ratio (HR) for OS limited to 5 years postoperatively.

RESULTS

Preoperative cutoff values were as follows: NLR > 10.2, PLR > 260, and SII > 2900. Overall, 35.9% (55/153) of patients had elevated NLR, 45.7% (70/153) had elevated PLR, and 30.7% (47/153) had elevated SII. The overall 30-day mortality was 8.5% (13/153). After controlling for confounders such as performance status and primary tumor type, high NLR (OR 5.20, 95% CI 1.21-22.28; p = 0.026) and SII (OR 4.92, 95% CI 1.17-20.63; p = 0.029) were associated with increased odds of 30-day postoperative mortality. The median OS time in the study population was 26 months (95% CI 12-40 months). After controlling for confounders such as Eastern Cooperative Oncology Group status, primary tumor, and hypoalbuminemia, high NLR was associated with shorter OS (HR 2.23, 95% CI 1.48-3.97; p = 0.003).

CONCLUSIONS

High preoperative NLR and SII were independently associated with 30-day postoperative mortality in this study. Elevated NLR was also found to be associated with shorter OS. The prognostic role of these metrics warrants further investigation.

Racial Differences in Perioperative Complications, Readmissions, and Mortalities After Elective Spine Surgery in the United States: A Systematic Review Using AI-Assisted Bibliometric Analysis

STUDY DESIGN

Systematic Review and Meta-analysis.

OBJECTIVES

To evaluate the impact of race on post-operative outcomes and complications following elective spine surgery in the United States.

METHODS

PUBMED, MEDLINE(R), ERIC, EMBASE, and SCOPUS were searched for studies documenting peri-operative events for White and African American (AA) patients following elective spine surgery. Pooled odds ratios were calculated for each 90-day outcome and meta-analyses were performed for 4 peri-operative events and 7 complication categories. Sub-analyses were performed for each outcome on single institution (SI) studies and works that included <100,000 patients.

RESULTS

53 studies (5,589,069 patients, 9.8% AA) were included. Eleven included >100,000 patients. AA patients had increased rates of 90-day readmission (OR 1.33, P = .0001), non-routine discharge (OR 1.71, P = .0001), and mortality (OR 1.66, P = .0003), but not re-operation (OR 1.16, P = .1354). AA patients were more likely to have wound-related complications (OR 1.47, P = .0001) or medical complications (OR 1.35, P = .0006), specifically cardiovascular (OR 1.33, P = .0126), deep vein thrombosis/pulmonary embolism (DVT/PE) (OR 2.22, P = .0188) and genitourinary events (OR 1.17, P = .0343). SI studies could only detect racial differences in re-admissions and non-routine discharges. Studies with <100,000 patients replicated the above findings but found no differences in cardiovascular complications. Disparities in mortality were only detected when all studies were included.

CONCLUSIONS

AA patients faced a greater risk of morbidity across several distinct categories of peri-operative events. SI studies can be underpowered to detect more granular complication types (genitourinary, DVT/PE). Rare events, such as mortality, require larger sample sizes to identify significant racial disparities.

Disparities in postoperative complications and perioperative events based on insurance status following elective spine surgery: A systematic review and meta-analysis

Background

Increasing evidence demonstrates disparities among patients with differing insurance statuses in the field of spine surgery. However, no pooled analyses have performed a robust review characterizing differences in postoperative outcomes among patients with varying insurance types.

Methods

A comprehensive literature search of the PUBMED, MEDLINE(R), ERIC, and EMBASE was performed for studies comparing postoperative outcomes in patients with private insurance versus government insurance. Pooled incidence rates and odds ratios were calculated for each outcome and meta-analyses were conducted for 3 perioperative events and 2 types of complications. In addition to pooled analysis, sub-analyses were performed for each outcome in specific government payer statuses.

Results

Thirty-eight studies (5,018,165 total patients) were included. Compared with patients with private insurance, patients with government insurance experienced greater risk of 90-day re-admission (OR 1.84, p<.0001), non-routine discharge (OR 4.40, p<.0001), extended LOS (OR 1.82, p<.0001), any postoperative complication (OR 1.61, p<.0001), and any medical complication (OR 1.93, p<.0001). These differences persisted across outcomes in sub-analyses comparing Medicare or Medicaid to private insurance. Similarly, across all examined outcomes, Medicare patients had a higher risk of experiencing an adverse event compared with non-Medicare patients. Compared with Medicaid patients, Medicare patients were only more likely to experience non-routine discharge (OR 2.68, p=.0007).

Conclusions

Patients with government insurance experience greater likelihood of morbidity across several perioperative outcomes. Additionally, Medicare patients fare worse than non-Medicare patients across outcomes, potentially due to age-based discrimination. Based on these results, it is clear that directed measures should be taken to ensure that underinsured patients receive equal access to resources and quality care.

Crimping technique to treat iatrogenic vertebral artery injury during spinal fusion

Iatrogenic arterial injuries may occur during neurosurgical procedures. Particularly, the vertebral artery may be injured in a high-level cervical spinal fusion case, either during the initial exposure or when placing screws.1- 3 If such an injury occurs, obtaining hemostatic control and repairing the laceration are of paramount importance.4, 5 In this technical video, we describe the case of a patient who was undergoing a posterior C1-C2 cervical fusion when the right vertebral artery was injured due to variant anatomy. Using sutures to repair the injury was unsuccessful. Thus, we employed a technique known as crimping, which involves the use of vascular clips to pinch off the site of the tear. This technique is an improvement over existing methods given how quickly and easily it can be performed. In our technical video, we explain how to perform the crimping technique and discuss indications for its use. The patient consented to the procedure.

The prognostic nutritional index (PNI) is independently associated with 90-day and 12-month mortality after metastatic spinal tumor surgery

INTRODUCTION

Estimated postoperative survival is an important consideration during the decision-making process for patients with spinal metastases. Nutritional status has been associated with poor outcomes and limited survival in the general cancer population. The objective of this study was to evaluate the predictive utility of the prognostic nutritional index (PNI) for postoperative mortality after spinal metastasis surgery.

METHODS

A total of 139 patients who underwent oncologic surgery for spinal metastases between April 2012 and August 2022 and had a minimum 90-day follow-up were included. PNI was calculated using preoperative serum albumin and total lymphocyte count, with PNI < 40 defined as low. The mean PNI of our cohort was 43 (standard deviation: 7.7). The primary endpoint was 90-day mortality, and the secondary endpoint was 12-month mortality. Multivariate logistic regression analyses were performed.

RESULTS

The 90-day mortality was 27% (37/139), and the 12-month mortality was 56% (51/91). After controlling for age, ECOG performance status, total psoas muscle cross-sectional area (TPA), and primary cancer site, the PNI was associated with 90-day mortality [odds ratio 0.86 (95% confidence interval 0.79-0.94); p = 0.001]. After controlling for ECOG performance status and primary cancer site, the PNI was associated with 12-month mortality [OR 0.89 (95% CI 0.82-0.97); p = 0.008]. Patients with a low PNI had a 50% mortality rate at 90 days and an 84% mortality rate at 12 months.

CONCLUSION

The PNI was independently associated with 90-day and 12-month mortality after metastatic spinal tumor surgery, independent of performance status, TPA, and primary cancer site.

Is perioperative blood transfusion associated with postoperative thromboembolism or infection after metastatic spinal tumor surgery?

STUDY DESIGN

Retrospective cohort.

SUMMARY OF BACKGROUND DATA

Patients with metastatic spine disease who undergo surgical intervention have a high risk of requiring red blood cell (RBC) transfusion. Perioperative transfusion has been independently associated with increased risk of venous thromboembolic (VTE) and infectious complications following orthopedic procedures and degenerative spinal intervention; however, literature within spine oncology is limited.

OBJECTIVE

To determine the association between perioperative RBC transfusion and postoperative VTE or infection following spinal tumor surgery.

METHODS

A total of 153 patients who underwent surgery for spinal metastases between April 2012 and April 2022 were included. Medical records were reviewed to identify RBC transfusion administered either intraoperatively or within 96 h following surgery. The primary endpoints were: 1) development of any VTE or 2) development of any infection within 30 days following surgery. Any VTE was defined as deep vein thrombosis or pulmonary embolism, and any infection was defined as pneumonia, meningitis, Clostridium difficile infection, urinary tract infection, surgical site infection, or sepsis. Logistic regression analyses were performed.

RESULTS

Of the 153 patients included in the study, 43 % received a perioperative RBC transfusion. The overall incidence of postoperative VTE and infection was 15 % and 22 %, respectively. In univariate analysis, perioperative transfusion was not associated with postoperative VTE (odds ratio [OR] 2.41; 95 % confidence interval [CI] 0.97-6.00; p = 0.058) but was associated with infection (OR 3.02; 95 % CI 1.36-6.73; p = 0.007). After adjusting for confounders such as performance status, operative time, and surgical extent, transfusion was not associated with both VTE (OR 1.25; 95 % CI 0.36-4.32; p = 0.727) or infection (OR 1.86; 95 % CI 0.70-4.92; p = 0.210). While not statistically significant, sub-analyses demonstrated a trend towards increased VTE incidence in patients requiring transfusion earlier (within 24 h) as opposed to later postoperatively.

CONCLUSIONS

We found that perioperative transfusion was not an independent predictor of 30-day postoperative VTE or infection in patients undergoing metastatic spinal surgery. Further exploration of time-dependent transfusion outcomes is warranted.

Predictors of mortality in chronic subdural hematoma evacuation

Chronic subdural hematoma (cSDH) is one of the most common types of intracranial hemorrhages, particularly in the elderly. Despite extensive research regarding cSDH diagnosis and treatment, there is conflicting data on predictors of postoperative mortality (POM). We conducted a large retrospective review of patients who underwent a cSDH evacuation at a single urban institution between 2015 and 2022. Data were collected from the electronic medical record on prior comorbidities, anticoagulation use, mental status on presentation, preoperative labs, and preoperative/postoperative imaging parameters. Univariate and multivariate analyses were conducted to analyze predictors of mortality. Mortality during admission for this cohort was 6.1%. Univariate analysis showed the mortality rate was higher in those presenting with a history of dialysis. In addition, those who presented with altered mental status, were intubated, and lower GCS scores had higher rates of POM. Usage of Coumadin was correlated with higher rates of POM. Examination of preoperative labs showed that patients who presented with anemia or thrombocytopenia had higher POM. Imaging data showed that cSDH volume and greatest dimension were correlated with higher rates of POM. Finally, patients that were not extubated postoperatively had higher rates of POM. Multivariate analysis showed that only altered mental status and being not being extubated postoperatively were correlated with a higher risk of mortality. In summation, we demonstrated that altered mental status and failure to extubate were independent predictors or mortality in cSDH evacuation. Interestingly, patient age was not a significant predictor of mortality.

Predictive value of six nutrition biomarkers in oncological spine surgery: a performance assessment for prediction of mortality and wound infection

OBJECTIVE

Assessment of nutritional status is fundamental in cancer patients. The objective of this study was to assess the predictive ability of 6 nutritional biomarkers for postoperative mortality and wound infection after metastatic spinal tumor surgery.

METHODS

A total of 139 patients who underwent oncological surgery for metastatic spine disease between April 2012 and August 2022 and had a minimum follow-up of 90 days were included. Six unique nutritional biomarkers were assessed: Prognostic Nutritional Index (PNI), Nutritional Risk Index (NRI), Controlling Nutritional Status Score (CONUT), total psoas cross-sectional area (TPA), body mass index (BMI), and body weight. Study endpoints were 90-day mortality rate, 12-month mortality rate, and wound infection. The discriminative ability of each of these markers was assessed with the c-statistic. A multivariate analysis was done for each of the biomarkers after a univariate analysis was first performed.

RESULTS

The 90-day mortality rate was 27% (37 of 139). The biomarkers and respective c-statistics were as follows: PNI (0.74), NRI (0.75), CONUT (0.71), TPA (0.64), BMI (0.59), and body weight (0.60). The 12-month mortality rate was 56% (51 of 91). The biomarkers and respective c-statistics were as follows: PNI (0.72), NRI (0.73), CONUT (0.70), TPA (0.63), BMI (0.59), and body weight (0.60). The wound infection rate was 8% (11 of 139). The biomarkers and respective c-statistics were as follows: PNI (0.57), NRI (0.53), CONUT (0.55), TPA (0.57), BMI (0.48), and body weight (0.52). The PNI, NRI, and CONUT all predicted 90-day and 12-month mortality after multivariate regression analysis. No association between nutrition and wound infection was found.

CONCLUSIONS

In this study, nutritional status was associated with postoperative mortality following oncological spine surgery. Three biomarkers predicted outcome independent of variables such as performance status or primary cancer. Future validation of these metrics is needed.

A curious cervical spine case: multiple, primary CNS leiomyosarcomas presenting with rapid growth in the immunocompromised patient

INTRODUCTION

Primary CNS leiomyosarcomas are rare, dural-based intracranial or intravertebral tumors seen in immunocompromised patients and are associated with latent EBV infection. They may mimic a meningioma or schwannoma on imaging but their clinical presentation progresses much more rapidly. Often times, these tumors are hard to distinguish from secondary, metastatic leiomyosarcoma.

CASE PRESENTATION

A 30-year-old female with congenital HIV presented to clinic with shoulder pain, paresthesias of the right upper extremity and gait instability. She was noted to have a contrast enhancing dural-based spinal canal lesion measuring 1.5 cm at the C1 vertebral level on MRI. Surgery was proposed but patient deferred. She represented to our Emergency Department 1 month later with right-sided hemiparesis and difficulty with ambulation. On repeat MRI, the lesion had grown to 2.6 cm. She was taken to the OR emergently for gross total tumor resection. The histopathology demonstrated a primary CNS leiomyosarcoma. MRI scan of the brain revealed an extra-axial right frontal lobe lesion measuring 1.8 cm which was also treated with subtotal surgical resection followed by proton beam radiotherapy.

DISCUSSION

Primary CNS leiomyosarcomas should be considered in young immunocompromised patients presenting with dural-based spinal cord tumors. Histopathological studies including EBV testing can definitively make the diagnosis. These tumors have an aggressive nature and need to be treated with complete surgical resection to prevent severe neurological deterioration and adjuvant therapy to prevent recurrence.

Performance Assessment of the American College of Surgeons Risk Calculator in Metastatic Spinal Tumor Surgery

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to assess the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) surgical risk calculator performance in patients undergoing surgery for metastatic spine disease.

SUMMARY OF BACKGROUND DATA

Patients with spinal metastases may require surgical intervention for cord compression or mechanical instability. The ACS-NSQIP calculator was developed to assist surgeons with estimating 30-day postoperative complications based on patient-specific risk factors and has been validated within several surgical patient populations.

MATERIALS AND METHODS

We included 148 consecutive patients at our institution who underwent surgery for metastatic spine disease between 2012 and 2022. Our outcomes were 30-day mortality, 30-day major complications, and length of hospital stay (LOS). Predicted risk, determined by the calculator, was compared with observed outcomes using receiver operating characteristic curves with area under the curve (AUC) and Wilcoxon signed-rank tests. Analyses were repeated using individual corpectomy and laminectomy Current Procedural Terminology (CPT) codes to determine procedure-specific accuracy.

RESULTS

Based on the ACS-NSQIP calculator, there was good discrimination between observed and predicted 30-day mortality incidence overall (AUC=0.749), as well as in corpectomy cases (AUC=0.745) and laminectomy cases (AUC=0.788). Poor 30-day major complication discrimination was seen in all procedural cohorts, including overall (AUC=0.570), corpectomy (AUC=0.555), and laminectomy (AUC=0.623). The overall median observed LOS was similar to predicted LOS (9 vs. 8.5 d, P =0.125). Observed and predicted LOS were also similar in corpectomy cases (8 vs. 9 d; P =0.937) but not in laminectomy cases (10 vs. 7 d, P =0.012).

CONCLUSIONS

The ACS-NSQIP risk calculator was found to accurately predict 30-day postoperative mortality but not 30-day major complications. The calculator was also accurate in predicting LOS following corpectomy but not laminectomy. While this tool may be utilized to predict risk short-term mortality in this population, its clinical value for other outcomes is limited.

Can We Use Artificial Intelligence Cluster Analysis to Identify Patients with Metastatic Breast Cancer to the Spine at Highest Risk of Postoperative Adverse Events?

OBJECTIVE

Group patients who required open surgery for metastatic breast cancer to the spine by functional level and metastatic disease characteristics to identify factors that predispose to poor outcomes.

METHODS

A retrospective analysis included patients managed at 2 tertiary referral centers from 2008 to 2020. The primary outcome was a 90-day adverse event. A 2-step unsupervised cluster analysis stratified patients into cohorts using function at presentation, preoperative spine radiation, structural instability, epidural spinal cord compression (ESCC), neural deficits, and tumor location/hormone status. Comparisons were performed using χ2 test and one-way analysis of variance.

RESULTS

Five patient "clusters" were identified. High function (HIGH) had thoracic metastases and an Eastern Cooperative Oncology Group (ECOG) score of 1.0 ± 0.8. Low function/irradiated (LOW + RADS) had preoperative radiation and the lowest Karnofsky scores (56.0 ± 10.6). Estrogen receptor or progesterone receptor (ER/PR) positive patients had >90% estrogen/progesterone positivity and moderate Karnofsky scores (74.0 ± 11.5). Lumbar/noncompressive (NON-COMP) had the fewest patients with ESCC grade 2 or 3 epidural disease (42.1%, P < 0.001). Low function/neurologic deficits (LOW + NEURO) had ESCC grade 2 or 3 disease and neurologic deficits. Adverse event rates were 25.0% in the HIGH group, 73.3% in LOW + RADS, 24.0% in ER/PR, 31.6% in NON-COMP, and 60.0% in LOW + NEURO (P = 0.003).

CONCLUSIONS

Function at presentation, tumor hormone signature, radiation history, and epidural compression delineated postoperative trajectory. We believe our results can aid in expectation management and the identification of at-risk patients who may merit closer surveillance following surgical intervention.

Racial Disparities in Perioperative Morbidity Following Oncological Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To assess the impact of race on complications following spinal tumor surgery.

METHODS

Adults with cancer who underwent spine tumor surgery were identified in the American College of Surgeons National Surgical Quality Improvement Program datasets from 2012 to 2016. Clavien-Dindo Grade I-II (minor complications) and Clavien-Dindo Grade III-V (major complications including 30-day mortality) complications were compared between non-Hispanic Whites (NHW) and Black patients. A multivariable analysis was also conducted.

RESULTS

Of 1,226 identified patients, 85.9% were NHW (n = 1,053) and 14.1% were Black (n = 173). The overall rate of Grade I-II complications was 16.2%; 15.1% for NHW patients and 23.1% for Black patients (P = .008). On multivariable analysis, Black patients had significantly higher odds of having a minor complication (OR 1.87; 95% CI, 1.16-3.01; P = .010). On the other hand, the overall rate of Grade III-V complications was 13.3%; 12.5% for NHW patients and 16.2% for Black patients (P = .187). On multivariable analysis, Black race was not independently associated with major complications (OR 1.26; 95% CI, 0.71-2.23; P = .430). Median length of stay was 8 days (IQR 5-13) for NHW patients and 10 days (IQR 6-15) for Black patients (P = .011).

CONCLUSION

Black patients who underwent metastatic spinal tumor surgery were at a significantly increased risk of perioperative morbidity compared to NHW patients independent of baseline and operative characteristics. Major complications did not differ between groups. Race should be further studied in the context of metastatic spine disease to improve our understanding of these disparities.

Evaluation of lymphopenia as a predictor of postoperative mortality and major complications in patients undergoing surgery for metastatic spine tumors

OBJECTIVE

Lymphopenia is often seen in advanced metastatic disease and has been associated with poor postoperative outcomes. Limited research has been done to validate this metric in patients with spinal metastases. The objective of this study was to evaluate the capability of preoperative lymphopenia to predict 30-day mortality, overall survival (OS), and major complications in patients undergoing surgery for metastatic spine tumors.

METHODS

A total of 153 patients who underwent surgery for metastatic spine tumor between 2012 and 2022 and met the inclusion criteria were examined. Electronic medical record chart review was conducted to obtain patient demographics, comorbidities, preoperative laboratory values, survival time, and postoperative complications. Preoperative lymphopenia was defined as < 1.0 K/μL based on the institution's laboratory cutoff value and within 30 days prior to surgery. The primary outcome was 30-day mortality. Secondary outcomes were OS up to 2 years and 30-day postoperative major complications. Outcomes were assessed with logistic regression. Survival analyses were done using the Kaplan-Meier method with log-rank test and Cox regression. Receiver operating characteristic curves were plotted to classify the predictive ability of lymphocyte count as a continuous variable on outcome measures.

RESULTS

Lymphopenia was identified in 47% of patients (72 of 153). The overall 30-day mortality rate was 9% (13 of 153). In logistic regression analysis, lymphopenia was not associated with 30-day mortality (OR 1.35, 95% CI 0.43-4.21; p = 0.609). The mean OS in this sample was 15.6 months (95% CI 13.9-17.3 months), with no significant difference between patients with lymphopenia and those with no lymphopenia (p = 0.157). Cox regression analysis did not show an association between lymphopenia and survival (HR 1.44, 95% CI 0.87-2.39; p = 0.161). The major complication rate was 26% (39 of 153). In univariable logistic regression analysis, lymphopenia was not associated with the development of a major complication (OR 1.44, 95% CI 0.70-3.00; p = 0.326). Finally, receiver operating characteristic curves generated poor discrimination between lymphocyte count and all outcomes, including 30-day mortality (area under the curve 0.600, p = 0.232).

CONCLUSIONS

This study does not support prior research that had shown an independent association between low preoperative lymphocyte level and poor postoperative outcomes following surgery for metastatic spine tumors. Although lymphopenia may be used to predict outcomes in other tumor-related surgeries, this metric may not hold a similar predictive capability in the population undergoing surgery for metastatic spine tumors. Further research into reliable prognostic tools is needed.

Selecting the lowest instrumented vertebra in a multilevel posterior cervical fusion across the cervicothoracic junction: a biomechanical investigation

OBJECTIVE

Posterior cervical fusion is a common surgical treatment for patients with myeloradiculopathy or regional deformity. Several studies have found increased stresses at the cervicothoracic junction (CTJ) and significantly higher revision surgery rates in multilevel cervical constructs that terminate at C7. The purpose of this study was to investigate the biomechanical effects of selecting C7 versus T1 versus T2 as the lowest instrumented vertebra (LIV) in multisegmental posterior cervicothoracic fusion procedures.

METHODS

Seven fresh-frozen cadaveric cervicothoracic spines (C2-L1) with ribs intact were tested. After analysis of the intact specimens, posterior rods and lateral mass screws were sequentially added to create the following constructs: C3-7 fixation, C3-T1 fixation, and C3-T2 fixation. In vitro flexibility tests were performed to determine the range of motion (ROM) of each group in flexion-extension (FE), lateral bending (LB), and axial rotation (AR), and to measure intradiscal pressure of the distal adjacent level (DAL).

RESULTS

In FE, selecting C7 as the LIV instead of crossing the CTJ resulted in the greatest increase in ROM (2.54°) and pressure (29.57 pound-force per square inch [psi]) at the DAL in the construct relative to the intact specimen. In LB, selecting T1 as the LIV resulted in the greatest increase in motion (0.78°) and the lowest increase in pressure (3.51 psi) at the DAL relative to intact spines. In AR, selecting T2 as the LIV resulted in the greatest increase in motion (0.20°) at the DAL, while selecting T1 as the LIV resulted in the greatest increase in pressure (8.28 psi) in constructs relative to intact specimens. Although these trends did not reach statistical significance, the observed differences were most apparent in FE, where crossing the CTJ resulted in less motion and lower intradiscal pressures at the DAL.

CONCLUSIONS

The present biomechanical cadaveric study demonstrated that a cervical posterior fixation construct with its LIV crossing the CTJ produces less stress in its distal adjacent discs compared with constructs with C7 as the LIV. Future clinical testing is necessary to determine the impact of this finding on patient outcomes.

Performance assessment and external validation of specific thresholds of total psoas muscle cross-sectional area as predictors of mortality in oncologic spine surgery for spinal metastases

PURPOSE

The purpose of this study was to assess the utility of low muscle mass (LMM) in predicting 90-day and 12-month mortality after spinal tumor surgery.

METHODS

We identified 115 patients operated on for spinal metastases between April 2012 and August 2022 who had available perioperative abdominal or lumbar spine CT scans and minimum 90-day follow-up. LMM was defined as a total psoas muscle cross-sectional area (TPA) at the L4 pedicle level less than 10.5 cm² for men and less than 7.2 cm² for women based on previously reported thresholds. A secondary analysis was performed by analyzing TPA as a continuous variable. The primary endpoint was 90-day mortality, and the secondary endpoint was 12-month mortality. Multivariate logistic regression analyses were performed.

RESULTS

The 90-day mortality was 19% for patients without and 42% for patients with LMM (p = 0.010). After multivariate analysis, LMM was not independently associated with increased odds of 90-day mortality (odds ratio 2.16 [95% confidence interval 0.62 to 7.50]; p = 0.223). The 12-month mortality was 45% for patients without and 71% for patients with LMM (p = 0.024). After multivariate analysis, LMM was not independently associated with increased odds of 12-month mortality (OR 1.64 [95% CI 0.46 to 5.86]; p = 0.442). The secondary analysis showed no independent association between TPA and 90-day or 12-month mortality.

CONCLUSION

Patients with LMM had higher rates of 90-day and 12-month mortality in our study, but this was not independent of other parameters such as performance status, hypoalbuminemia, or primary cancer type.

Racial disparities in inpatient clinical presentation, treatment, and outcomes in brain metastasis

Background

Few studies have assessed the impact of race on short-term patient outcomes in the brain metastasis population. The goal of this study is to evaluate the association of race with inpatient clinical presentation, treatment, in-hospital complications, and in-hospital mortality rates for patients with brain metastases (BM).

Method

Using data collected from the National Inpatient Sample between 2004 and 2014, we retrospectively identified adult patients with a primary diagnosis of BM. Outcomes included nonroutine discharge, prolonged length of stay (pLOS), in-hospital complications, and mortality.

Results

Minority (Black, Hispanic/other) patients were less likely to receive surgical intervention compared to White patients (odds ratio [OR] 0.70; 95% confidence interval [CI] 0.66-0.74, p < 0.001; OR 0.88; 95% CI 0.84-0.93, p < 0.001). Black patients were more likely to develop an in-hospital complication than White patients (OR 1.35, 95% CI 1.28-1.41, p < 0.001). Additionally, minority patients were more likely to experience pLOS than White patients (OR 1.48; 95% CI 1.41-1.57, p < 0.001; OR 1.34; 95% CI 1.27-1.42, p < 0.001). Black patients were more likely to experience a nonroutine discharge (OR 1.25; 95% CI 1.19-1.31, p < 0.001) and higher in-hospital mortality than White (OR 1.13; 95% CI 1.03-1.23, p = 0.008).

Conclusion

Our analysis demonstrated that race is associated with disparate short-term outcomes in patients with BM. More efforts are needed to address these disparities, provide equitable care, and allow for similar outcomes regardless of care.

Are There Racial or Socioeconomic Disparities in Ambulatory Outcome or Survival After Oncologic Spine Surgery for Metastatic Cancer? Results From a Medically Underserved Center

BACKGROUND

Disparities among patients with cancer are well documented. Recent studies suggest these disparities also affect patients undergoing metastatic spinal tumor surgery. However, it is unclear whether social factors are associated with ambulatory outcomes or overall survival.

QUESTIONS/PURPOSES

In patients undergoing metastatic spinal tumor surgery, (1) Are race, Social Vulnerability Index (SVI) score, or insurance status associated with a lower likelihood of postoperative ambulation? (2) Are race, SVI score, or insurance status associated with shorter overall survival?

METHODS

Between April 2012 and June 2021, we surgically treated 148 patients for metastatic cord compression or spinal mechanical instability because of cancer. Inclusion criteria were patients with complete demographic, social, oncologic, and follow-up data and patients who were followed until death or for at least 3 months postoperatively. Based on these criteria, 12% (18 of 148) were excluded because they had incomplete data and another 7% (11 of 148) were excluded because they were lost before the minimum study follow-up interval, leaving 80% (119) for analysis. Collected social data included self-reported race (White, Black, Hispanic or Latino, or other), SVI score, and primary insurance (Medicare, Medicaid, or private). The median age of the group was 62 years (interquartile range [IQR] 53 to 70 years), and 58% of patients were men (69 of 119). The race distribution was 45% Black (54 of 119), 32% Hispanic or Latino (38 of 119), 16% White (19 of 119), and 7% other (eight of 119). The median SVI score was 89.8 (IQR 73.8 to 98.5), and 74% of patients (88) were categorized as having high vulnerability. The insurance distribution was as follows: Medicare: 43%, Medicaid: 36%, and private insurance: 21%. The primary outcome variable was complete inability to ambulate postoperatively and the secondary outcome was median overall survival. Exploratory data analysis, univariate and multivariate logistic regression, and univariate and multivariate Cox regression analyses were performed.

RESULTS

After controlling for race, SVI score, insurance status, primary cancer, and modified Bauer score, the only factor independently associated with postoperative nonambulation was preoperative nonambulatory status (odds ratio 59.3 [95% confidence interval (CI) 13.2 to 266.1]; p < 0.001). After controlling for variables such as performance status, BMI, primary cancer, modified Bauer score, and insurance status, factors independently associated with survival included Eastern Cooperative Oncology Group performance status (hazard ratio [HR] 1.4 [95% CI 1.1 to 2.0]; p = 0.03), prostate cancer (HR 0.4 [95% CI 0.1 to 0.9]; p = 0.03), and hematologic cancer (HR 0.3 [95% CI 0.1 to 0.8]; p = 0.02). Race, SVI score, and insurance status were not associated with overall survival.

CONCLUSION

In this study, we found no difference in ambulatory outcome for patients based on their race, SVI score, or insurance status. Likewise, no differences in postoperative survival were found. These findings suggest that despite differences in presentation or short-term outcome reported in other investigations, the social factors we explored were not associated with the likelihood of a patient being nonambulatory postoperatively or shorter survival after spinal tumor surgery. Research studies that analyze race as a covariate of interest should take care to explore metrics of socioeconomic deprivation (such as the SVI score) to avoid drawing misleading conclusions.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The Effect of a Multidisciplinary Spine Clinic on Time to Care in Patients with Chronic Back and/or Leg Pain: A Propensity Score-Matched Analysis

Chronic back and leg pain are leading causes of disability worldwide. The purpose of this study was to compare the care in a unidisciplinary (USC) versus multidisciplinary (MSC) spine clinic, where patients are evaluated by different specialists during the same office visit. Adult patients presenting with a chief complaint of back and/or leg pain between June 2018 and July 2019 were assessed for eligibility. The main outcome measures included the first treatment recommendations, the time to treatment order, and the time to treatment occurrence. A 1:1 propensity score-matched analysis was performed on 874 patients (437 in each group). For all patients, the most common recommendation was physical therapy (41.4%), followed by injection (14.6%), and surgery (9.7%). Patients seen in the MSC were more likely to be recommended injection (p < 0.001) and less likely to be recommended surgery as first treatment (p = 0.001). They also had significantly shorter times to the injection order (log-rank test, p = 0.004) and the injection occurrence (log-rank test, p < 0.001). In this study, more efficient care for patients with back and/or leg pain was delivered in the MSC setting, which was evidenced by the shorter times to the injection order and occurrence. The impact of the MSC approach on patient satisfaction and health-related quality-of-life outcome measures warrants further investigation.

Acute Cauda Equina Syndrome Due to Spondylolisthesis in the Midst of a Pandemic: A Case Report

CASE

A 54-year-old woman with chronic lumbar radiculopathy due to grade II spondylolisthesis at lumbar 4 to 5 developed acute cauda equina syndrome (CES) after an elective lumbar decompression, and fusion was delayed because of statewide bans on elective procedures during the pandemic. The diagnosis was made largely through telehealth consultation and eventually prompted urgent neurosurgical intervention.

CONCLUSION

This case report illustrates a rare presentation of acute CES and highlights some of the challenges of practicing clinical medicine in the midst of a pandemic.

Comparison of three predictive scoring systems for morbidity in oncological spine surgery

Estimating complications in oncological spine surgery is challenging. The objective of this study was to compare the accuracy of three scoring systems for predicting perioperative morbidity after surgery for spinal metastases. One-hundred and five patients who underwent surgery between 2013 and 2019 were included in this study. All patients had scores retrospectively calculated using the New England Spinal Metastasis Score (NESMS), Metastatic Spinal Tumor Frailty Index (MSTFI), and Anzuategui scoring systems. The main outcome measure was development of a medical complication (minor or major) within 30 days of surgery. The predictive ability for each system was assessed using receiver operating characteristic analysis and calculations of the area under the curve (AUC). The average age for all patients was 61 years and 61/105 patients (58.1%) were male. The most common primary tumor origins were hematologic (23.8%), prostate (16.2%), breast (14.3%), and lung (13.3%). The overall 30-day complication rate was 36.2% and the rate of major complications was 21.9%. Among all patients who underwent oncological spine surgery, the NESMS score had the highest AUC for 30-day overall (AUC 0.64; 95% CI, 0.53 - 0.75) and major morbidity (AUC 0.68; 95% CI, 0.54- 0.81) in our population. However, the accuracy did not meet the threshold for clinical utility. Future prospective validation of these systems in other populations is encouraged.

Insurance status as a mediator of clinical presentation, type of intervention, and short-term outcomes for patients with metastatic spine disease

BACKGROUND

It is well established that insurance status is a mediator of disease management, treatment course, and clinical outcomes in cancer patients. Our study assessed differences in clinical presentation, treatment course, mortality rates, and in-hospital complications for patients admitted to the hospital with late-stage cancer - specifically, metastatic spine disease (MSD), by insurance status.

METHODS

The United States National Inpatient Sample (NIS) database (2012-2014) was queried to identify patients with visceral metastases, metastatic spinal cord compression (MSCC) or pathological fracture of the spine in the setting of cancer. Clinical presentation, type of intervention, mortality rates, and in-hospital complications were compared amongst patients by insurance coverage (Medicare, Medicaid, commercial or unknown). Multivariable logistical regression and age sensitivity analyses were performed.

RESULTS

A total of 48,560 MSD patients were identified. Patients with Medicaid coverage presented with significantly higher rates of MSCC (p < 0.001), paralysis (0.008), and visceral metastases (p < 0.001). Patients with commercial insurance were more likely to receive surgical intervention (OR 1.43; p < 0.001). Patients with Medicaid < 65 had higher rates of prolonged length of stay (PLOS) (OR 1.26; 95% CI, 1.01-1.55; p = 0.040) while both Medicare and Medicaid patients < 65 were more likely to have non-routine discharges. In-hospital mortality rates were significantly higher for patients with Medicaid (OR 2.66; 95% CI 1.20-5.89; p = 0.016) and commercial insurance (OR 1.58; 95% CI 1.09-2.27;p = 0.013) older than 65.

CONCLUSION

Given the differing severity in MSD presentation, mortality rates, and rates of PLOS by insurance status, our results identify disparities based on insurance coverage.

Predictive value of hypoalbuminemia and severe hypoalbuminemia in oncologic spine surgery

STUDY DESIGN

Retrospective review of a prospectively collected national database.

OBJECTIVE

To evaluate the predictive value of hypoalbuminemia on outcomes in surgical spine oncology patients.

SUMMARY OF BACKGROUND DATA

It is well documented that patients with hypoalbuminemia (albumin <3.5) have significantly higher rates of surgical morbidity and mortality than patients with normal albumin (>3.5 g/dl). We evaluated outcomes for metastatic oncologic spine surgery patients based on pre-operative albumin levels.

MATERIALS AND METHODS

Patients who underwent surgery for metastatic spine disease were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2006 to 2016. Three groups were established: patients with normal albumin (>3.5 g/dl), mild hypoalbuminemia (2.6 g/dl - 3.4 g/dl), and severe hypoalbuminemia (<=2.5 g/dl). A multivariate analysis was used to assess the association between albumin levels and mortality within 30 days of surgical intervention.

RESULTS

A total of 700 patients who underwent surgery for metastatic spinal disease and had pre-operative albumin levels available were identified; 64.0% had normal albumin (>3.5 g/dl), 29.6% had mild hypoalbuminemia, and 6.4% had severe hypoalbuminemia. The overall 30-day mortality was 7.6% for patients with normal albumin, 15.9% for patients with mild hypoalbuminemia, and 44.4% for patients with severe hypoalbuminemia. On multivariate analysis, patients with mild hypoalbuminemia (OR 1.7 95% CI: 1.0-3.0 p = 0.05) and severe hypoalbuminemia (OR 6.2 95% CI: 2.8-13.5 p < 0.001) were more likely to expire within 30 days compared to patients with preoperative albumin above 3.5 g/dl.

CONCLUSION

In this study, albumin level was found to be an independent predictor of 30-day mortality in patients who underwent operative intervention for metastatic spinal disease. Patients with severe hypoalbuminemia had a 7-fold increased risk when compared with those who had normal albumin. While these findings need to be validated by future studies, we believe they will prove useful for preoperative risk stratification and surgical decision-making.

Association of Medicare and Medicaid Insurance Status with Increased Spine Surgery Utilization Rates

STUDY DESIGN

Retrospective single-institution study.

OBJECTIVE

The aim of this study was to determine the relationship between patients' insurance status and the likelihood for them to be recommended various spine interventions upon evaluation in our neurosurgical clinics.

SUMMARY OF BACKGROUND DATA

Socioeconomically disadvantaged populations have worse outcomes after spine surgery. No studies have looked at the differential rates of recommendation for surgery for patients presenting to spine surgeons based on socioeconomic status.

METHODS

We studied patients initially seeking spine care from spine-fellowship trained neurosurgeons at our institution from July 1, 2018 to June 30, 2019. Multivariable logistic regression was used to assess the association between insurance status and the recommended patient treatment.

RESULTS

Overall, 663 consecutive outpatients met inclusion criteria. Univariate analysis revealed a statistically significant association between insurance status and treatment recommendations for surgery (P < 0.001). Multivariate logistic regression demonstrated that compared with private insurance, Medicare (odds ratio [OR] 3.54, 95% confidence interval [CI] 1.21-7.53, P = 0.001) and Medicaid patients (OR 2.46, 95% CI 1.21-5.17, P = 0.014) were more likely to be recommended for surgery. Uninsured patients did not receive recommendations for surgery at significantly different rates than patients with private insurance.

CONCLUSION

Medicare and Medicaid patients are more likely to be recommended for spine surgery when initially seeking spine care from a neurosurgeon. These findings may stem from a number of factors, including differential severity of the patient's condition at presentation, disparities in access to care, and differences in shared decision making between surgeons and patients.Level of Evidence: 3.

Minimally Invasive Tubular Separation Surgery for Metastatic Spinal Cord Compression: 2-Dimensional Operative Video

Symptomatic cord compression affects approximately 20% of patients with spinal metastatic disease. Direct decompressive surgery followed by conventional radiation was shown to be superior to radiation alone in a landmark trial published in 2005.1 For radioresistant tumors causing high-grade compression, however, "separation surgery" followed by stereotactic body radiation therapy was developed. The main goal of this newer technique is to decompress and create a distance between the spinal cord and tumor to allow for safe delivery of radiation.2 This technique has shown to provide durable local tumor control, pain relief, and preservation of neurological function.3,4 In this study, we describe a minimally invasive tubular separation surgery technique used to treat symptomatic cord compression in a 59-yr-old man with metastatic prostate adenocarcinoma to T9. The patient presented with acute motor weakness and sensory level. A tubular retraction system was used to dock over the pedicle at T9 bilaterally and a posterior decompression with ligamentectomy was first performed. This was followed by transpedicular decompression and ventral removal of the posterior longitudinal ligament. Space was created between the ventral tumor and spinal cord to allow for postoperative stereotactic body radiation. The patient had a significant improvement in his strength and gait postoperatively. Patient consent was obtained for videotaping prior to surgical intervention.

Surgical Outcomes for Upper Lumbar Disc Herniations: A Systematic Review and Meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

To conduct a literature review on outcomes of discectomy for upper lumbar disc herniations (ULDH), estimate pooled rates of satisfactory outcomes, compare open laminectomy/microdiscectomy (OLM) versus minimally invasive surgical (MIS) techniques, and compare results of disc herniations at L1-3 versus L3-4.

METHODS

A systematic review of articles reporting outcomes of nonfusion surgical treatment of L1-2, L2-3, and/or L3-4 disc herniations was performed. The inclusion and exclusion of studies was performed according to the latest version of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

RESULTS

A total of 20 articles were included in the quantitative meta-analysis. Pooled proportion of satisfactory outcome (95% CI) was 0.77 (0.70, 0.83) for MIS and 0.82 (0.78, 0.84) for OLM. There was no significant improvement with MIS techniques compared with standard OLM, odds ratio (OR) = 0.86, 95% CI (0.42, 1.74), P = .66. Separating results by levels revealed a trend of higher satisfaction with L3-4 versus L1-3 with OLM surgery, OR = 0.46, 95% CI (0.19, 1.12), P = .08.

CONCLUSION

Our analysis reveals that discectomy for ULDH has an overall success rate of approximately 80% and has not improved with MIS. Discectomy for herniations at L3-4 trends toward better outcomes compared with L1-2 and L2-3, but was not significant.

A Systematic Review of Treatment Strategies for the Prevention of Junctional Complications After Long-Segment Fusions in the Osteoporotic Spine

STUDY DESIGN

Systematic review.

OBJECTIVES

Proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) are well-known complications after long-segment fusions in the thoracolumbar spine of osteoporotic patients. Recent advances in anti-resorptive and anabolic medications, instrumentation, surgical technique, and cement augmentation have all aided in the avoidance of junctional kyphosis. In this article, current literature on the prevention of PJK and PJF in the osteoporotic spine is reviewed.

METHODS

A systematic literature review was conducted using the PubMed/MEDLINE and Embase databases in order to search for the current preventive treatment methods for PJK and PJF published in the literature (1985 to present). Inclusion criteria included (1) published in English, (2) at least 1-year mean and median follow-up, (3) preoperative diagnosis of osteoporosis, (4) at least 3 levels instrumented, and (5) studies of medical treatment or surgical techniques for prevention of junctional kyphosis.

RESULTS

The review of the literature yielded 7 studies with low levels of evidence ranging from level II to IV. Treatment strategies reviewed addressed prophylaxis against ligamentous failure, adjacent vertebral compression fracture, and/or bone-implant interface failure. This includes studies on the effect of osteoporosis medication, cement augmentation, multi-rod constructs, and posterior-tension band supplementation. The role of perioperative teriparatide therapy maintains the highest level of evidence.

CONCLUSIONS

Perioperative teriparatide therapy represents the strongest evidence for preventive treatment, and further clinical trials are warranted. Use of cement augmentation, sublaminar tethers, and multi-rod constructs have low or insufficient evidence for recommendations. Future guidelines for adult spinal deformity correction may consider bone mineral density-adjusted alignment goals.

Separation surgery for metastatic epidural spinal cord compression: comparison of a minimally invasive versus open approach

OBJECTIVE

The aim of this study was to compare outcomes of separation surgery for metastatic epidural spinal cord compression (MESCC) in patients undergoing minimally invasive surgery (MIS) versus open surgery.

METHODS

A retrospective study of patients undergoing MIS or standard open separation surgery for MESCC between 2009 and 2019 was performed. Both groups received circumferential decompression via laminectomy and a transpedicular approach for partial corpectomy to debulk ventral epidural disease, as well as instrumented stabilization. Outcomes were compared between the two groups.

RESULTS

There were 17 patients in the MIS group and 24 in the open surgery group. The average age of the MIS group was significantly older than the open surgery group (65.5 vs 56.6 years, p < 0.05). The preoperative Karnofsky Performance Scale score of the open group was significantly lower than that of the MIS group, with averages of 63.0% versus 75.9%, respectively (p = 0.02). This was also evidenced by the higher proportion of emergency procedures performed in the open group (9 of 24 patients vs 0 of 17 patients, p = 0.004). The average Spine Instability Neoplastic Score, number of levels fused, and operative parameters, including length of stay, were similar. The average estimated blood loss difference for the open surgery versus the MIS group (783 mL vs 430 mL, p < 0.05) was significant, although the average amount of packed red blood cells transfused was not significantly different (325 mL vs 216 mL, p = 0.39). Time until start of radiation therapy was slightly less in the MIS than the open surgery group (32.8 ± 15.6 days vs 43.1 ± 20.3 days, p = 0.069). Among patients who underwent open surgery with long-term follow-up, 20% were found to have local recurrence compared with 12.5% of patients treated with the MIS technique. No patients in either group developed hardware failure requiring revision surgery.

CONCLUSIONS

MIS for MESCC is a safe and effective approach for decompression and stabilization compared with standard open separation surgery, and it significantly reduced blood loss during surgery. Although there was a trend toward a faster time to starting radiation treatment in the MIS group, both groups received similar postoperative radiotherapy doses, with similar rates of local recurrence and hardware failure. An increased ability to perform MIS in emergency settings as well as larger, prospective studies are needed to determine the potential benefits of MIS over standard open separation surgery.

Interhospital transfer status for spinal metastasis patients in the United States is associated with more severe clinical presentations and higher rates of inpatient complications

OBJECTIVE

In patients with metastatic spinal disease (MSD), interhospital transfer can potentially impact clinical outcomes as the possible benefits of transferring a patient to a higher level of care must be weighed against the negative effects associated with potential delays in treatment. While the association of clinical outcomes and transfer status has been examined in other specialties, the relationship between transfer status, complications, and risk of mortality in patients with MSD has yet to be explored. The purpose of this study was to examine the impact of transfer status on in-hospital mortality and clinical outcomes in patients diagnosed with MSD.

METHODS

The National (Nationwide) Inpatient Sample (NIS) database was retrospectively queried for adult patients diagnosed with vertebral pathological fracture and/or spinal cord compression in the setting of metastatic disease between 2012 and 2014. Demographics, baseline characteristics (e.g., metastatic spinal cord compression [MSCC] and paralysis), comorbidities, type of intervention, and relevant patient outcomes were controlled in a multivariable logistic regression model to analyze the association of transfer status with patient outcomes.

RESULTS

Within the 10,360 patients meeting the inclusion and exclusion criteria, higher rates of MSCC (50.2% vs 35.9%, p < 0.001) and paralysis (17.3% vs 8.4%, p < 0.001) were observed in patients transferred between hospitals compared to those directly admitted. In univariable analysis, a higher percentage of transferred patients underwent surgical intervention (p < 0.001) when compared with directly admitted patients. After controlling for significant covariates and surgical intervention, transferred patients were more likely to develop in-hospital complications (OR 1.34, 95% CI 1.18-1.52, p < 0.001), experience prolonged length of stay (OR 1.33, 95% CI 1.16-1.52, p < 0.001), and have a discharge disposition other than home (OR 1.70, 95% CI 1.46-1.98, p < 0.001), with no significant difference in inpatient mortality rates.

CONCLUSIONS

Patients with MSD who were transferred between hospitals demonstrated more severe clinical presentations and higher rates of inpatient complications compared to directly admitted patients, despite demonstrating no difference in in-hospital mortality rates.

The Role of Biological Fusion and Anterior Column Support in a Long Lumbopelvic Spinal Fixation and Its Effect on the S1 Screw-An In Silico Biomechanics Analysis

STUDY DESIGN

Finite element analysis.

OBJECTIVE

The aim of this study was to determine the role of biological fusion and anterior column support in a long lumbopelvic spinal fixation.

SUMMARY OF BACKGROUND DATA

Retrospective studies have shown that adding anterior column support is not sensitive to construct failure, highlighting that posterior fusion quality may be a more important factor.

METHODS

Finite element models were created to match the average spinal-pelvic parameters of two patient cohorts reported in the literature: major failure and nonfailure. A moment load was applied at the T10 superior endplate to simulate gravimetric loading in a standing position. Effects of three factors on the biomechanical behavior of a fused spine were evaluated: sagittal alignment; posterior fusion versus no fusion; and anterior support at L4-S1 versus no anterior support.

RESULTS

Sagittal balance of the major failure group was positively correlated with 15% higher translation, 14% higher rotation, and 16% higher stress than in the nonfailure group. Simulated posterior fusion-only decreased motion by 32% and 29%, and alleviated rod stress by 15% and 5% and S1 screw stress by 26% and 35%, respectively, in major failure and non-failure groups. The addition of anterior fusion without posterior fusion did not help with rod stress alleviation but dramatically decreased S1 screw stress (by 57% and 41%), respectively. With both posterior fusion and anterior support, screw stress at the S1 was decreased by additional 30% and 6%, respectively.

CONCLUSION

The spinopelvic parameters of the major failure group produced increased gravity load, resulting in increased stresses in comparison to the nonfailure group. Simulated posterior "solid" fusion in the lumbar region helped reduce stresses in both major failure and nonfailure patients. Anterior column support was an important factor in reducing S1 screw stress, with or without posterior fusion, and should be considered for patients with poor alignment.Level of Evidence: N/A.

Gender disparities in clinical presentation, treatment, and outcomes in metastatic spine disease

BACKGROUND

The incidence of metastatic spine disease (MSD) is increasing among cancer patients. Given the poor outcomes and high rates of morbidity associated with MSD, it is important to determine demographic factors that could impact interventions and outcomes for this patient population. The objectives of this study were to compare in-hospital mortality and complication rates, clinical presentation, and interventions between female and male patients diagnosed with MSD.

METHODS

Patient data were collected from the United States National Inpatient Sample (NIS) database from the years 2012-2014. Descriptive statistics were used to compare data from 51,800 cases; subsequently, multivariable logistic regression analyses were conducted to assess the effect of gender on outcomes.

RESULTS

Males had significantly higher rates of in-hospital mortality (OR 1.30; 95 % CI 1.09-1.56, p = 0.004) and were more likely to have received surgical intervention than females (OR 1.34; 95 % CI 1.16-1.55, p < 0.001). Additionally, female patients were more likely to present with vertebral compression fracture (p < 0.001), while metastatic spinal cord compression (MSCC) and paralysis were more common in male patients (p < 0.001). There was no significant difference in rates of in-hospital complications between female and male patients.

CONCLUSION

Given the significant differences in mortality, disease course, treatment, and in-hospital complications between female and male patients diagnosed with MSD, additional prospective studies are necessary to understand how to meaningfully incorporate these differences into clinical care and prognostication going forward.

A Multidisciplinary Spine Surgical Indications Conference Leads to Alterations in Surgical Plans in a Significant Number of Cases: A Case Series

STUDY DESIGN

Case series.

OBJECTIVE

To evaluate the impact of a multidisciplinary spine surgery indications conference (MSSIC) on surgical planning for elective spine surgeries.

SUMMARY OF BACKGROUND DATA

Identifying methods for pairing the proper patient with the optimal intervention is of the utmost importance for improving spine care and patient outcomes. Prior studies have evaluated the utility of multidisciplinary spine conferences for patient management, but none have evaluated the impact of a MSSIC on surgical planning and decision making.

METHODS

We implemented a mandatory weekly MSSIC with all spine surgeons at our institution. Each elective spine surgery in the upcoming week is presented. Subsequently, a group consensus decision is achieved regarding the best treatment option based on the expertise and opinions of the participating surgeons. We reviewed cases presented at the MSSIC from September 2019 to December 2019. We compared the surgeon's initial proposed surgery for a patient with the conference attendees' consensus decision on the best treatment and measured compliance rates with the group's recommended treatment.

RESULTS

The conference reviewed 100 patients scheduled for elective spine surgery at our indications conference during the study period. Surgical plans were recommended for alteration in 19 cases (19%) with the proportion statistically significant from zero indicated by a binomial test (P < 0.001). The median absolute change in the invasiveness index of the altered procedures was 3 (interquartile range [IQR] 1-4). Participating surgeons complied with the group's recommendation in 96.5% of cases.

CONCLUSION

In conjunction with other multidisciplinary methods, MSSICs can lead to surgical planning alterations in a significant number of cases. This could potentially result in better selection of surgical candidates and procedures for particular patients. Although long-term patient outcomes remain to be evaluated, this care model will likely play an integral role in optimizing the care spine surgeons provide patients.

LEVEL OF EVIDENCE

4.

Comparison of 30-Day Outcomes in Patients with Cervical Spine Metastasis Undergoing Corpectomy Versus Posterior Cervical Laminectomy and Fusion: A 2006-2016 ACS-NSQIP Database Study

BACKGROUND

Patients with metastatic disease to the cervical spine have historically had poor outcomes, with an average survival of 15 months. Every effort should be made to avoid complications of surgical intervention for stabilization and decompression.

METHODS

We identified patients who had undergone anterior cervical corpectomy and fusion (ACCF) or posterior cervical laminectomy and fusion (PCLF) for metastatic disease of the cervical spine using the American College of Surgeons National Surgical Quality Improvement Program database from 2006 to 2016. Patients meeting the inclusion criteria were subsequently propensity matched 1:1. We compared the overall complications, intensive care unit level complications, mortality, and return to the operating room between the 2 groups.

RESULTS

After identifying the patients who met the inclusion criteria and propensity matching, a cohort of 240 patients was included, with 120 (50%) in the ACCF group and 120 (50%) in the PCLF group. The patients in the ACCF group were more likely to have experienced any complication (odds ratio, 2.1; 95% confidence interval, 1.1-4.1; P = 0.026) but not severe complications or a return to the operating room (P = 0.406 and P = 0.450, respectively).

CONCLUSION

In the present study, we found that anterior surgical approaches (ACCF) for metastatic cervical spine disease resulted in a significantly greater rate of overall complications (2.1 times more) compared with PCLF in the first 30 days. Although more studies are required to further elucidate this relationship, the general belief that the anterior approach is better tolerated by patients might not apply to patients with metastatic tumors.

Prolonged length of stay and discharge disposition to rehabilitation facilities following single-level posterior lumbar interbody fusion for acquired spondylolisthesis

Background

Acquired lumbar spondylolisthesis is often treated with interbody fusion. However, few studies have evaluated predictors for prolonged length of stay (LOS) and disposition to rehabilitation facilities after posterior single-level lumbar interbody fusion for acquired spondylolisthesis.

Methods

The American College of Surgeons National Quality Improvement Program database was queried for adults with acquired spondylolisthesis who underwent single-level lumbar interbody fusion through a posterior approach (posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion [TLIF]). We utilized multivariate logistic regression analysis to identify predictors of prolonged LOS and disposition in this patient population.

Results

Among 2080 patients identified, 700 (33.7%) had a prolonged LOS (≥4 days), and 306 (14.7%) were discharged postoperatively to rehabilitation facilities. Predictors for prolonged LOS included: American Society of Anesthesiologist (ASA) class ≥3, anemia, prolonged operative time, perioperative blood transfusion, pneumonia, urinary tract infections, and return to the operating room. The following risk factors predicted discharge to postoperative rehabilitation facilities: age ≥65 years, male sex, ASA class ≥3, modified frailty score ≥2, perioperative blood transfusion, and prolonged LOS.

Conclusion

Multiple partial-overlapping risk factors predicted prolonged LOS and discharge to rehabilitation facilities after single-level TLIF/PLIF performed for acquired spondylolisthesis.

Early Medical Complications and Delayed Discharge after Spinopelvic Fusion: A Comparative Analysis of 887 NSQIP Cases from 2006 to 2016

Introduction

The effect of pelvic fixation on postoperative medical complications, blood transfusion, length of hospital stay, and discharge disposition is poorly understood. Determining factors that predispose patients to increased complications after spinopelvic fusion will help surgeons to plan these complex procedures and optimize patients preoperatively.

Methods

We conducted a retrospective cohort study using data from the ACS-NSQIP database between 2006 and 2016 of patients who underwent lumbar fusion with and without spinopelvic fixation. Data regarding demographics, complications, hospital stay, and discharge disposition were collected.

Results

A total of 57,417 (98.5%) cases of lumbar fusion without spinopelvic fixation (LF) and 887 (1.5%) cases of lumbar fusion with spinopelvic fixation (SPF) were analyzed. The transfusion rate in the SPF group was 59.3% vs 13% in the LF group (p < 0.001). The mean length of stay (LOS) and discharge to skilled nursing facility (SNF) were significantly different (LOS: SPF 6.5 days vs LF 3.5 days p < 0.001; SNF: SPF 21.3% vs LF 10.4% p < 0.001). After controlling for demographic differences, the overall complication rates were not significantly different between the groups (p = 0.531). The odds ratio for transfusion in the SPF group was 2.9 (p < 0.001). The odds ratio for increased LOS and increased care discharge disposition were elevated in the SPF group (LOS OR: 1.3, p < 0.012, Discharge disposition OR: 1.8, p < 0.001).

Conclusions

Patients who underwent SPF had increased complications, transfusion rate, LOS, and discharge to SNF or subacute rehab facilities as compared with patients who underwent LF. SPF remains an effective technique for achieving lumbosacral arthrodesis. Surgeons should consider the implications of the associated complication profile for SPF and the value of preoperative optimization in a select cohort of patients.

Accuracy of Freehand versus Navigated Thoracolumbar Pedicle Screw Placement in Patients with Metastatic Tumors of the Spine

Objective

To compare the accuracy and breach rates of freehand (FH) versus navigated (NV) pedicle screws in the thoracic and lumbar spine in patients with metastatic spinal tumors.

Methods

A retrospective review of adult patients who underwent pedicle screw fixation in the thoracic or lumbar spine for metastatic spinal tumors between 2012 and 2018 was conducted. Breaches were assessed based on the Gertzbein and Robbins classification and only screws placed >4 mm outside of the pedicle wall (lateral or medial) were considered breached.

Results

A total of 62 patients received 547 pedicle screws (average 8 per patient) – 34 patients received 298 pedicle screws in the FH group and 28 patients received 249 screws in the NV group. There were 40/547 breaches, corresponding to a breach and accuracy rate of 7.3% and 92.7%, respectively. The breach rate was 9.7% in the FH group and 4.4% in the NV group (chi-squared test, p=0.017); this corresponded to an accuracy rate of 90.3% and 95.6%, respectively. Only one patient from the overall cohort (in the FH group) required revision surgery due to a medial breach abutting the spinal cord (1.6% of all patients; 2.9% of FH patients); no patient suffered organ, vessel, or neurological injury from screw breaches.

Conclusion

Navigated pedicle screw placement in patients with metastatic spinal tumors has a significantly higher radiographic accuracy compared to the FH technique. However, the revision surgery was low and no patient suffered from clinically-relevant breach. Navigation also offers the advantage of real-time localization of spinal tumors and aids in targeting and resection of these lesions.

COVID-19 Infection Among Healthcare Workers: Serological Findings Supporting Routine Testing

A growing body of evidence demonstrates that asymptomatic and pre-symptomatic transmission of SARS-CoV-2 is a major contributor to the COVID-19 pandemic. Frontline healthcare workers in COVID-19 hotspots have faced numerous challenges, including shortages of personal protective equipment (PPE) and difficulties acquiring clinical testing. The magnitude of the exposure of healthcare workers and the potential for asymptomatic transmission makes it critical to understand the incidence of infection in this population. To determine the prevalence of asymptomatic SARS-CoV-2 infection amongst healthcare workers, we studied frontline staff working in the Montefiore Health System in New York City. All participants were asymptomatic at the time of testing and were tested by RT-qPCR and for anti-SARS-CoV-2 antibodies. The medical, occupational, and COVID-19 exposure histories of participants were recorded via questionnaires. Of the 98 asymptomatic healthcare workers tested, 19 (19.4%) tested positive by RT-qPCR and/or ELISA. Within this group, four (4.1%) were RT-qPCR positive, and four (4.1%) were PCR and IgG positive. Notably, an additional 11 (11.2%) individuals were IgG positive without a positive PCR. Two PCR positive individuals subsequently developed COVID-19 symptoms, while all others remained asymptomatic at 2-week follow-up. These results indicate that there is considerable asymptomatic infection with SARS-CoV-2 within the healthcare workforce, despite current mitigation policies. Furthermore, presuming that asymptomatic staff are not carrying SARS-CoV-2 is inconsistent with our results, and this could result in amplified transmission within healthcare settings. Consequently, aggressive testing regiments, such as testing frontline healthcare workers on a regular, multi-modal basis, may be required to prevent further spread within the workforce and to patients.