Pre-contoured patient-specific rods result in superior immediate sagittal plane alignment than surgeon contoured rods in adolescent idiopathic scoliosis.

Background: Adolescent idiopathic scoliosis (AIS) surgery typically involves posterior spinal fusion (PSF) using rods contoured by the surgeon, which may be time-consuming and may not reliably restore optimal sagittal alignment. However, pre-contoured patient-specific rods may more optimally restore sagittal spinal alignment. This study evaluates the radiographic outcomes of AIS patients who underwent PSF utilizing surgeon contoured vs. pre-contoured rods. Methods: This is a retrospective cohort study of AIS patients who underwent PSF with either surgeon contoured or pre-contoured rods. Demographics, Lenke classification, fused levels, osteotomies, estimated blood loss (EBL), and surgical time were also obtained via chart review. Coronal curve magnitude, T5-T12 thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), PI-LL mismatch, and T1 pelvic angle (TPA) were obtained pre-operatively, postoperatively and at last follow up. Outcome measures included rate of achievement of postoperative radiographic alignment goals (TK between 20 and 40 degrees, PI-LL mismatch within 10 degrees, and TPA <14 degrees). Predicted post-operative sagittal alignment was also compared with observed measurements. Student's and paired t-tests were performed to determine significant mean differences for continuous variables, and chi-square for categorical variables. Results: No differences were found in demographics, Lenke classification, preop radiographic measurements, fused levels, osteotomies, EBL, and surgical time in the surgeon contoured cohort (n=36; average follow up 11.3 months) and pre-contoured cohort (n=22; average follow up 9.7 months). At last follow up, 95.5% of patients with pre-contoured rods vs. 61.1% of patients with surgeon contoured rods (P=0.004) met TK goal. During assessment of first standing postoperative X-ray, 72.7% of patients with pre-contoured rods vs. 33.3% of patients with surgeon contoured rods met PI-LL mismatch goal (P=0.004). Other radiographic measurements were similar. Artificial intelligence (AI) predicted and observed differences for the pre-contoured group were 3.7 for TK (P=0.005), -7.6 for PI-LL mismatch (P=0.002), and -2.6 for TPA (P=0.11). Conclusions: AI and pre-contoured rods help achieve global sagittal balance with high accuracy and improved kyphosis restoration and PI-LL mismatch than surgeon contoured rods in AIS patients.

Selective Liquid-Liquid Extraction of Thorium(IV) from Rare-Earth Element Mixtures.

One of the major challenges in processing rare-earth element (REE) materials arises from the large amounts of radioactive thorium (Th) that are often found within REE minerals, encouraging enhanced metal separation procedures. We report here a study aimed at developing improved systems for REE processing with the goal of efficient extraction of Th(IV) from acidic solution. A tripodal ligand, TRPN-CMPO-Ph, was prepared that utilizes carbamoylmethylphosphine oxide (CMPO) chelators tethered to a tris(3-aminopropyl)amine (TRPN) capping scaffold. The ligand and its metal complexes were characterized by using elemental analysis, NMR, Fourier transform infrared spectroscopy, mass spectrometry, and luminescence spectroscopy. Using a liquid-liquid metal extraction protocol, TRPN-CMPO-Ph selectively extracts Th(IV) at an efficiency of 79% from a mixture of Th(IV), UO22+, and all rare-earth metal cations (except promethium) dissolved in nitric acid into an organic solvent. Th(IV) extraction selectivity is maintained upon extraction from a mixture that approximates a typical monazite leach solution containing several relevant lanthanide ions, including two ions at higher concentration relative to Th(IV). Comparative studies with a tris(2-aminoethyl)amine (TREN)-capped derivative are presented and support the need for a larger TRPN capping scaffold in achieving Th(IV) extraction selectivity.

Electron Paramagnetic Resonance, Electronic Ground State, and Electron Spin Relaxation of Seven Lanthanide Ions Bound to Lanmodulin and the Bioinspired Chelator, 3,4,3-LI(1,2-HOPO).

The electron paramagnetic resonance (EPR) spectra of lanthanide(III) ions besides Gd3+ , bound to small-molecule and protein chelators, are uncharacterized. Here, the EPR properties of 7 lanthanide(III) ions bound to the natural lanthanide-binding protein, lanmodulin (LanM), and the synthetic small-molecule chelator, 3,4,3-LI(1,2-HOPO) ("HOPO"), were systematically investigated. Echo-detected pulsed EPR spectra reveal intense signals from ions for which the normal continuous-wave first-derivative spectra are negligibly different from zero. Spectra of Kramers lanthanide ions Ce3+ , Nd3+ , Sm3+ , Er3+ , and Yb3+ , and non-Kramers Tb3+ and Tm3+ , bound to LanM are more similar to the ions in dilute aqueous:ethanol solution than to those coordinated with HOPO. Lanmodulins from two bacteria, with distinct metal-binding sites, had similar spectra for Tb3+ but different spectra for Nd3+ . Spin echo dephasing rates (1/Tm ) are faster for lanthanides than for most transition metals and limited detection of echoes to temperatures below ~6 to 12 K. Dephasing rates were environment dependent and decreased in the order water:ethanol>LanM>HOPO, which is attributed to decreasing librational motion. These results demonstrate that the EPR spectra and relaxation times of lanthanide(III) ions are sensitive to coordination environment, motivating wider application of these methods for characterization of both small-molecule and biomolecule interactions with lanthanides.

Impact of insurance status on healthcare resource utilization and outcomes in adolescent patients presenting with spinal cord injuries.

OBJECTIVE: Insurance disparities have been suggested to influence the medical and surgical outcomes of adult patients with spinal cord injury (SCI), with a paucity of studies demonstrating their impact on the outcomes of pediatric and adolescent SCI patients. The aim of this study was to assess the impact of insurance status on healthcare utilization and outcomes in adolescent patients presenting with SCI. METHODS: An administrative database study was performed using the 2017 admission year from 753 facilities using the National Trauma Data Bank. Adolescent patients (11-17 years old) with cervical/thoracic SCIs were identified using International Classification of Diseases, Tenth Revision, Clinical Modification coding. Patients were categorized by governmental insurance versus private insurance/self-pay. Patient demographics, comorbidities, imaging, procedures, hospital adverse events (AEs), and length of stay (LOS) data were collected. Multivariate regression analyses were used to determine the effect of insurance status on LOS, any imaging or procedure, or any AE. RESULTS: Of the 488 patients identified, 220 (45.1%) held governmental insurance while 268 (54.9%) were privately insured. Age was similar between the cohorts (p = 0.616), with the governmental insurance cohort (GI cohort) having a significantly lower proportion of non-Hispanic White patients than the private insurance cohort (PI cohort) (GI: 43.2% vs PI: 72.4%, p < 0.001). While transportation accident was the most common mechanism of injury for both cohorts, assault was significantly greater in the GI cohort (GI: 21.8% vs PI: 3.0%, p < 0.001). A significantly greater proportion of patients in the PI cohort received any imaging (GI: 65.9% vs PI: 75.0%, p = 0.028), while there were no significant differences in procedures performed (p = 0.069) or hospital AEs (p = 0.386) between the cohorts. The median (IQR) LOS (p = 0.186) and discharge disposition (p = 0.302) were similar between the cohorts. On multivariate analysis, with respect to governmental insurance, private insurance was not independently associated with obtaining any imaging (OR 1.38, p = 0.139), undergoing any procedure (OR 1.09, p = 0.721), hospital AEs (OR 1.11, p = 0.709), or LOS (adjusted risk ratio -2.56, p = 0.203). CONCLUSIONS: This study suggests that insurance status may not independently influence healthcare resource utilization and outcomes in adolescent patients presenting with SCIs. Further studies are needed to corroborate these findings.

Association Between Intravenous to Oral Opioid Transition Time and Length of Hospital Stay After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

BACKGROUND: Transitioning from intravenous (IV) to oral opioids after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) is necessary during the postoperative course. However, few studies have assessed the effects of longer transition times on hospital length of stay (LOS). This study investigated the impact of longer IV to oral opioid transition times on LOS after PSF for AIS. METHODS: The medical records of 129 adolescents (10-18 years old) with AIS undergoing multilevel PSF at a major academic institution from 2013 to 2020 were reviewed. Patients were categorized by IV to oral opioid transition time: normal (≤2 days) vs prolonged (≥3 days). Patient demographics, comorbidities, deformity characteristics, intraoperative variables, postoperative complications, and LOS were assessed. Multivariate analyses were used to determine odds ratios for risk-adjusted extended LOS. RESULTS: Of the 129 study patients, 29.5% (n = 38) had prolonged IV to oral transitions. Demographics and comorbidities were similar between the cohorts. The major curve degree (P = 0.762) and median (interquartile range) levels fused (P = 0.447) were similar between cohorts, but procedure time was significantly longer in the prolonged cohort (normal: 6.6 ± 1.2 hours vs prolonged: 7.2 ± 1.3 hours, P = 0.009). Postoperative complication rates were similar between the cohorts. Patients with prolonged transitions had significantly longer LOS (normal: 4.6 ± 1.3 days vs prolonged: 5.1 ± 0.8 days, P < 0.001) but similar discharge disposition (P = 0.722) and 30-day readmission rates (P > 0.99). On univariate analysis, transition time was significantly associated with extended LOS (OR: 2.0, 95% CI [0.9, 4.6], P = 0.014), but this assocation was not significant on multivariate analysis (adjusted OR: 2.1, 95% CI [1.3, 4.8], P = 0.062). CONCLUSIONS: Longer postoperative IV to oral opioid transitions after PSF for AIS may have implications for hospital LOS.

Effects of delayed ambulation following posterior spinal fusion for adolescent idiopathic scoliosis: a single institutional study.

OBJECTIVE: Mobilizing out of bed and ambulation are key components of recovery following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). However, there remains a paucity of studies identifying risk factors associated with delayed ambulation and its impact on postoperative outcomes. The aim of this study was to investigate patient- and surgical-level risk factors associated with delayed ambulation and the ramifications of delayed ambulation on healthcare utilization for patients undergoing PSF for AIS. METHODS: The medical records of 129 adolescent (10-18 years) patients diagnosed with AIS undergoing posterior spinal fusion at a major academic institution between 2013 and 2020 were reviewed. Patients were categorized based on days from surgery to ambulation: early (≤ 1 day), intermediate (2 days), or late (≥ 3 days). Patient demographics, comorbidities, spinal deformity characteristics, intraoperative variables, postoperative complications, LOS, and unplanned readmissions were assessed. The odds ratios for risk-adjusted delayed ambulation and extended LOS were determined via multivariate stepwise logistic regressions. RESULTS: One Hundred and Twenty Nine patients were included in this study, of which 10.8% (n = 14) were classified as Early ambulators, 41.9% (n = 54) Intermediate ambulators, and 47.3% (n = 61) were Late ambulators. Late ambulators were significantly younger than early and intermediate ambulators (Early: 15.7 ± 1.9 years vs. Intermediate: 14.8 ± 1.7 years vs. Late: 14.1 ± 1.9 years, p = 0.010). The primary and secondary spinal curves were significantly worse among Late ambulators (p < 0.001 and p = 0.002 respectively). Fusion levels (p < 0.01), EBL (p = 0.014), and the rate of RBC transfusions (p < 0.001) increased as time to ambulation increased. Transition time from IV to oral pain medications (Early: 1.6 ± 0.8 days vs. Intermediate: 2.2 ± 0.6 days vs. Late: 2.4 ± 0.6 days, p < 0.001) and total hospital length of stay (Early: 3.9 ± 1.4 days vs. Intermediate: 4.7 ± 0.9 days vs. Late: 5.1 ± 1.2 days, p < 0.001) were longer in Late ambulators. On multivariate analysis, significant predictors of delayed ambulation included primary curve degree ≥ 70° [aOR: 5.67 (1.29‒31.97), p = 0.030] and procedure time [aOR: 1.66 (1.1‒2.59), p = 0.019]. CONCLUSIONS: Our study suggests that there may be patient- and surgical-level factors that are independently associated with late ambulation following PSF for AIS, including extent of major curve and length of operative time. Additionally, delayed ambulation has implications to length of hospital stay and postoperative complications.

Differences in Outcomes and Health Care Resource Utilization After Surgical Intervention for Metastatic Spinal Column Tumor in Safety-Net Hospitals.

STUDY DESIGN: Observational cohort study. OBJECTIVE: The aim of this study was to investigate the association between safety-net hospital (SNH) status and hospital length of stay (LOS), cost, and discharge disposition in patients undergoing surgery for metastatic spinal column tumors. SUMMARY OF BACKGROUND DATA: SNHs serve a high proportion of Medicaid and uninsured patients. However, few studies have assessed the effects of SNH status on outcomes after surgery for metastatic spinal column tumors. PATIENTS AND METHODS: This study was performed using the 2016-2019 Nationwide Inpatient Sample database. All adult patients undergoing metastatic spinal column tumor surgeries, identified using ICD-10-CM coding, were stratified by SNH status, defined as hospitals in the top quartile of Medicaid/uninsured coverage burden. Hospital characteristics, demographics, comorbidities, intraoperative variables, postoperative complications, and outcomes were assessed. Multivariable analyses identified independent predictors of prolonged LOS (>75th percentile of cohort), nonroutine discharge, and increased cost (>75th percentile of cohort). RESULTS: Of the 11,505 study patients, 24.0% (n = 2760) were treated at an SNH. Patients treated at SNHs were more likely to be Black-identifying, male, and lower income quartile. A significantly greater proportion of patients in the non-SNH (N-SNH) cohort experienced any postoperative complication [SNH: 965 (35.0%) vs . N-SNH: 3535 (40.4%), P = 0.021]. SNH patients had significantly longer LOS (SNH: 12.3 ± 11.3 d vs . N-SNH: 10.1 ± 9.5 d, P < 0.001), yet mean total costs (SNH: $58,804 ± 39,088 vs . N-SNH: $54,569 ± 36,781, P = 0.055) and nonroutine discharge rates [SNH: 1330 (48.2%) vs . N-SNH: 4230 (48.4%), P = 0.715) were similar. On multivariable analysis, SNH status was significantly associated with extended LOS [odds ratio (OR): 1.41, P = 0.009], but not nonroutine discharge disposition (OR: 0.97, P = 0.773) or increased cost (OR: 0.93, P = 0.655). CONCLUSIONS: Our study suggests that SNHs and N-SNHs provide largely similar care for patients undergoing metastatic spinal tumor surgeries. Patients treated at SNHs may have an increased risk of prolonged hospitalizations, but comorbidities and complications likely contribute greater to adverse outcomes than SNH status alone. LEVEL OF EVIDENCE: 3.

Impact of Racial Disparities on All-Cause Mortality in Patients With Tumors of the Spinal Cord or Spinal Meninges: A Propensity-Score Analysis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The influence that race has on mortality rates in patients with spinal cord tumors is relatively unknown. The aim of this study was to investigate the influence of race on the outcomes of patients with primary malignant or nonmalignant tumors of the spinal cord or spinal meninges. METHODS: The Surveillance, Epidemiology, and End Results (SEER) Registry was used to identify all patients with a code for primary malignant or nonmalignant tumor of the spinal cord (C72.0) or spinal meninges (C70.1) from 1973 through 2016. Racial groups (African-American/Black vs. White) were balanced using propensity-score (PS) matching using a non-parsimonious 1:1 nearest neighbor matching algorithm. Overall survival (OS) estimates were obtained using the Kaplan-Meier method and compared across non-PS-matched and PS-matched groups using log-rank tests. Associations of survival with clinical variables was assessed using doubly robust Cox proportional-hazards (CPH) regression analysis. RESULTS: There were a total of 7,498 patients identified with 648 (6.8%) being African American. African-American patients with primary intradural spine tumors were more likely to die of all causes than were White patients in both the non-PS-matched [HR: 1.26, 95% CI: (1.04, 1.51), P = 0.01] and PS-matched cohorts [HR: 1.64, 95% CI: (1.28, 2.11), P < 0.0001]. On multivariate CPH regression analysis age at diagnosis [HR: 1.03, 95% CI: (1.02, 1.05), P < 0.0001], race [HR: 1.82, 95% CI: (1.22, 2.74), P = 0.004), and receipt of RT [HR: 2.62, 95% CI: (1.56, 4.37), P = 0.0002) were all significantly associated with all-cause mortality, when controlling for other demographic, tumor, and treatment variables. CONCLUSIONS: Our study provides population-based estimates of the prognosis for patients with primary malignant or nonmalignant tumors of the spinal cord or spinal meninges and suggests that race may impact all-cause mortality.

Prospective analysis of home narcotic consumption and management of excess narcotic prescription following adolescent idiopathic scoliosis surgery.

PURPOSE: The aim of this study was to identify factors associated with the outpatient narcotic intake of patients following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) and to introduce a safe and effective method of disposing of unused narcotics. METHODS: Following Institutional Review Board approval, retrospective review of prospectively collected data from patients undergoing PSF for AIS took place. Pain scores, narcotic use, patient demographic data, pre-, intra-, and postoperative parameters, and discharge data were gathered via chart review. Patients were divided into two groups according to home narcotic use, high use (top 25th percentiles) and low use (bottom 75th percentiles), and multivariate statistical analysis was conducted. Narcotic surplus was collected during postoperative clinic visits and disposed of using biodegradable bags. RESULTS: Statistical analysis of 27 patients included in the study showed that patients with a higher home narcotic use correlated with increased length of hospitalization with an average of 3.4 days compared to the lower-use group of 2.8 day (p = 0.03). Higher-use group also showed increased inpatient morphine milligram equivalent than the lower-use group. There was no significant difference of home narcotic use when looking at patient age, height, weight, BMI, levels fused, intraoperative blood loss, or length of surgery. A total of 502 narcotic doses were disposed of in the clinic. CONCLUSION: Our study suggests that there are not a significant number of patient- or surgical-level factors predisposing patients to increased home narcotic usage following spinal fusion for adolescent idiopathic scoliosis. LEVEL OF EVIDENCE: Level I, prospective study.

Leveraging HFRS to assess how frailty affects healthcare resource utilization after elective ACDF for CSM.

BACKGROUND CONTEXT: Frailty is a common comorbidity associated with worsening outcomes in various medical and surgical fields. The Hospital Frailty Risk Score (HFRS) is a recently developed tool which assesses frailty using 109 International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) comorbidity codes to assess severity of frailty. However, there is a paucity of studies utilizing the HFRS with patients undergoing anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM). PURPOSE: The aim of this study was to investigate the impact of HFRS on health care resource utilization following ACDF for CSM. STUDY DESIGN: A retrospective cohort study was performed using the Nationwide Inpatient Sample (NIS) database from 2016-2019. PATIENT SAMPLE: All adult (≥18 years old) patients undergoing primary, ACDF for CSM were identified using the ICD-10 CM codes. OUTCOME MEASURES: Weighted patient demographics, comorbidities, perioperative complications, LOS, discharge disposition, and total admission costs were assessed. METHODS: The 109 ICD-10 codes with pre-assigned values from 0.1 to 7.1 pertaining to frailty were queried in each patient, with a cumulative HFRS ≥5 indicating a frail patient. Patients were then categorized as either Low HFRS (HFRS<5) or Moderate to High HFRS (HFRS≥5). A multivariate stepwise logistic regression was used to determine the odds ratio for risk-adjusted extended LOS, non-routine discharge disposition, and increased hospital cost. RESULTS: A total of 29,305 patients were identified, of which 3,135 (10.7%) had a Moderate to High HFRS. Patients with a Moderate to High HFRS had higher rates of 1 or more postoperative complications (Low HFRS: 9.5% vs. Moderate-High HFRS: 38.6%, p≤.001), significantly longer hospital stays (Low HFRS: 1.8±1.7 days vs. Moderate-High HFRS: 4.4 ± 6.0, p≤.001), higher rates of non-routine discharge (Low HFRS: 5.8% vs. Moderate-High HFRS: 28.2%, p≤.001), and increased total cost of admission (Low HFRS: $19,691±9,740 vs. Moderate-High HFRS: $26,935±22,824, p≤.001) than patients in the Low HFRS cohort. On multivariate analysis, Moderate to High HFRS was found to be a significant independent predictor for extended LOS [OR: 3.19, 95% CI: (2.60, 3.91), p≤.001] and non-routine discharge disposition [OR: 3.88, 95% CI: (3.05, 4.95), p≤.001] but not increased cost [OR: 1.10, 95% CI: (0.87, 1.40), p=.418]. CONCLUSIONS: Our study suggests that patients with a higher HFRS have increased total hospital costs, a longer LOS, higher complication rates, and more frequent nonroutine discharge compared with patients with a low HFRS following elective ACDF for CSM. Although frail patients should not be precluded from surgical management of cervical spine pathology, these findings highlight the need for peri-operative protocols to medically optimize patients to improve health care quality and decrease costs.

A comparison of in-hospital outcomes after elective anterior cervical discectomy and fusion in cases with and without Parkinson's Disease.

Background: Following orthopedic surgery, patients with Parkinson's disease (PD) have been shown to have high rates of surgical complications, and some studies suggest that PD may be associated with greater risk for postoperative medical complications. As complication rates are critical to consider for elective surgery planning, the current study aimed to describe the association of PD with medical complications following anterior cervical discectomy and fusion (ACDF), the most commonly performed procedure to treat cervical degenerative pathology. Methods: The 2008-2018 National Inpatient Sample database was queried for cases involving elective ACDF. Demographics and comorbidities were extracted using ICD codes. Cases were propensity matched based on demographic and comorbidity burden, and logistic regression was used to compare in-hospital complications between patients with and without PD. Results: After weighting, a total of 1,273,437 elective ACDF cases were identified, of which 3948 (0.31%) involved cases with PD. After 1:1 propensity score matching by demographic and comorbidity variables, there were no differences between the PD and non-PD cohorts. Logistic regression models constructed for the matched and unmatched populations showed that PD cases have greater odds of in-hospital minor adverse events with no differences in odds of serious adverse events or mortality. Conclusions: After matching for demographics and comorbidity burden, PD cases undergoing elective ACDF had slightly longer length of stay and greater risk for minor adverse events but had similar rates of serious adverse events and mortality. These findings are important for surgeons and patients to consider when making decisions about surgical intervention.

Analysis of the Frequency, Characteristics, and Reasons for Termination of Spine-related Clinical Trials.

STUDY DESIGN: Cross-sectional analysis of completed and terminated spine-related clinical trials in the ClinicalTrials.gov registry. OBJECTIVE: The aim was to quantify completed and terminated spine-related clinical trials, assess reasons for termination, and determine predictors of termination by comparing characteristics of completed and terminated trials. SUMMARY OF BACKGROUND DATA: Clinical trials are key to the advancement of products and procedures related to the spine. Unfortunately, trials may be terminated before completion. ClinicalTrials.gov is a registry and results database maintained by the National Library of Medicine that catalogs trial characteristics and tracks overall recruitment status (eg, ongoing, completed, terminated) for each study as well as reasons for termination. Reasons for trial termination have not been specifically evaluated for spine-related clinical trials. METHODS: The ClinicalTrials.gov database was queried on July 20, 2021 for all completed and terminated interventional studies registered to date using all available spine-related search terms. Trial characteristics and reason for termination, were abstracted. Univariate and multivariate analyses were performed determine predictors of trial termination. RESULTS: A total of 969 clinical trials were identified and characterized (833 completed, 136 terminated). Insufficient rate of participant accrual was the most frequently reported reason for trial termination, accounting for 33.8% of terminated trials.Multivariate analysis demonstrated increased odds of trial termination for industry-sponsorship [odds ratio (OR)=1.59] relative to sponsorship from local groups, device studies (OR=2.18) relative to investigations of drug or biological product(s), and phase II (OR=3.07) relative to phase III studies ( P <0.05 for each). CONCLUSIONS: Spine-related clinical trials were found to be terminated 14% of the time, with insufficient accrual being the most common reason for termination. With significant resources put into clinical studies and the need to advance scientific objectives, predictors, and reasons for trial termination should be considered and optimized to increase the completion rate of trials that are initiated.

Geographic variations in health care resource utilization following elective ACDF for cervical spondylotic myelopathy: A national trend analysis.

BACKGROUND: As health care expenditures continue to increase, standardizing health care delivery across geographic regions has been identified as a method to reduce costs. However, few studies have demonstrated how the practice of elective spine surgery varies by geographic location. The aim of this study was to assess the geographic variations in management, complications, and total cost of elective anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM). METHODS: The National Inpatient Sample database (2016-2017) was queried using the ICD-10-CM procedural and diagnostic coding systems to identify all adult (≥18 years) patients with a primary diagnosis of CSM undergoing an elective ACDF. Patients were divided into regional cohorts as defined by the U.S. Census Bureau: Northeast, Midwest, South, and West. Weighted patient demographics, Elixhauser comorbidities, perioperative complications, length of stay (LOS), discharge disposition, and total cost of admission were assessed. RESULTS: A total of 17,385 adult patients were identified. While the age (p=0.116) and proportion of female patients (p=0.447) were similar among the cohorts, race (p<0.001) and healthcare coverage (p<0.001) varied significantly. The Northeast had the largest proportion of patients in the 76-100th household income quartile (Northeast: 32.1%; Midwest: 16.9%; South: 15.7%; West: 27.5%, p<0.001). Complication rates were similar between regional cohorts (Northeast: 10.1%; Midwest: 12.2%; South: 10.3%; West: 11.9%, p=0.503), as was LOS (Northeast: 2.2±2.4 days; Midwest: 2.1±2.4 days; South: 2.0±2.5 days; West: 2.1±2.4 days, p=0.678). The West incurred the greatest mean total cost of admission (Northeast: $19,167±10,267; Midwest: $18,903±9,114; South: $18,566±10,152; West: $24,322±15,126, p<0.001). The Northeast had the lowest proportion of patients with a routine discharge (Northeast: 72.0%; Midwest: 84.8%; South: 82.3%; West: 83.3%, p<0.001). The odds ratio for Western hospital region was 3.46 [95% CI: (2.41, 4.96), p<0.001] compared to the Northeast for increased cost. CONCLUSION: Our study suggests that regional variations exist in elective ACDF for CSM, including patient demographics, hospital costs, and nonroutine discharges, while complication rates and LOS were similar between regions.

Octogenarians Are Independently Associated With Extended LOS and Non-Routine Discharge After Elective ACDF for CSM.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to determine the impact age has on LOS and discharge disposition following elective ACDF for cervical spondylotic myelopathy (CSM). METHODS: A retrospective cohort study was performed using the National Inpatient Sample (NIS) database from 2016 and 2017. All adult patients >50 years old undergoing ACDF for CSM were identified using the ICD-10-CM diagnosis and procedural coding system. Patients were then stratified by age: 50 to 64 years-old, 65 to 79 years-old, and greater than or equal to 80 years-old. Weighted patient demographics, comorbidities, perioperative complications, LOS, discharge disposition, and total cost of admission were assessed. RESULTS: A total of 14 865 patients were identified. Compared to the 50-64 and 65-79 year-old cohorts, the 80+ years cohort had a significantly higher rate of postoperative complication (50-64 yo:10.2% vs. 65-79 yo:12.6% vs. 80+ yo:18.9%, P = 0.048). The 80+ years cohort experienced significantly longer hospital stays (50-64 yo: 2.0 ± 2.4 days vs. 65-79 yo: 2.2 ± 2.8 days vs. 80+ yo: 2.3 ± 2.1 days, P = 0.028), higher proportion of patients with extended LOS (50-64 yo:18.3% vs. 65-79 yo:21.9% vs. 80+ yo:28.4%, P = 0.009), and increased rates of non-routine discharges (50-64 yo:15.1% vs. 65-79 yo:23.0% vs. 80+ yo:35.8%, P < 0.001). On multivariate analysis, age 80+ years was found to be a significant independent predictor of extended LOS [OR:1.97, 95% CI:(1.10,3.55), P = 0.023] and non-routine discharge [OR:2.46, 95% CI:(1.44,4.21), P = 0.001]. CONCLUSIONS: Our study demonstrates that octogenarian age status is a significant independent risk factor for extended LOS and non-routine discharge after elective ACDF for CSM.

Ramifications of Postoperative Dysphagia on Health Care Resource Utilization Following Elective Anterior Cervical Discectomy and Interbody Fusion for Cervical Spondylotic Myelopathy.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: The aim of this study was to investigate patient risk factors and health care resource utilization associated with postoperative dysphagia following elective anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: There is a paucity of data on factors predisposing patients to dysphagia and the burden this complication has on health care resource utilization following ACDF. METHODS: A retrospective cohort study was performed using the Nationwide Inpatient Sample (NIS) database from 2016 to 2017. All adult (above 18 y old) patients undergoing ACDF for cervical spondylotic myelopathy were identified using the ICD-10-CM diagnosis and procedural coding system. Patients were then categorized by whether they had a recorded postoperative dysphagia or no dysphagia. Weighted patient demographics, comorbidities, perioperative complications, length of hospital stay (LOS), discharge disposition, and total cost of admission were assessed. A multivariate stepwise logistic regression was used to determine both the odds ratio for risk-adjusted postoperative dysphagia as well as extended LOS. RESULTS: A total of 17,385 patients were identified, of which 1400 (8.1%) experienced postoperative dysphagia. Compared with the No-Dysphagia cohort, the Dysphagia cohort had a greater proportion of patients experiencing a complication (P=0.004), including 1 complication (No-Dysphagia: 2.9% vs. Dysphagia: 6.8%), and >1 complication (No-Dysphagia: 0.3% vs. Dysphagia: 0.4%). The Dysphagia cohort experienced significantly longer hospital stays (No-Dysphagia: 1.9±2.1 d vs. Dysphagia: 4.2±4.3 d, P<0.001), higher total cost of admission (No-Dysphagia: $19,441±10,495 vs. Dysphagia: $25,529±18,641, P<0.001), and increased rates of nonroutine discharge (No-Dysphagia: 16.5% vs. Dysphagia: 34.3%, P<0.001). Postoperative dysphagia was found to be a significant independent risk factor for extended LOS on multivariate analysis, with an odds ratio of 5.37 (95% confidence interval: 4.09, 7.05, P<0.001). CONCLUSION: Patients experiencing postoperative dysphagia were found to have significantly longer hospital LOS, higher total cost of admission, and increased nonroutine discharge when compared with the patients who did not. LEVEL OF EVIDENCE: Level III.

Hospital Consumer Assessment of Healthcare Providers and Systems survey response rates are significantly affected by patient characteristics and postoperative outcomes for patients undergoing primary total knee arthroplasty.

INTRODUCTION: The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey measures patients' satisfaction of their hospital experience. A minority of discharged patients return the survey. Underlying bias among who ultimately returns the survey (non-response bias) after total knee arthroplasty (TKA) may affect results of the survey. Thus, the objective of the current study is to assess the relationship between patient characteristics and postoperative outcomes on HCAHPS survey nonresponse. METHODS: All adult patients at a single institution undergoing inpatient, elective, primary TKA between February 2013 and May 2020 were selected for analysis. Following discharge, all patients had been mailed the HCAHPS survey. The primary outcome analyzed in the current study is survey return. Patient characteristics, surgical variables, and 30-day postoperative outcomes were analyzed. Univariate and multivariate analyses were performed to identify factors independently associated with return of the HCAHPS survey. RESULTS: Of 4,804 TKA patients identified, 1,498 (31.22%) returned HCAHPS surveys. On multivariate regression analyses controlling for patient factors, patients who did not return the survey were more likely to have a higher American Society of Anesthesia score (ASA score of 4 or higher, OR = 2.37; P<0.001), and be partially or totally dependent (OR = 2.37; P = 0.037). Similarly, patients who did not return the survey were more likely to have had a readmission (OR = 1.94; P<0.001), be discharged to a place other than home (OR = 1.52; P<0.001), or stay in the hospital for longer than 3 days (OR = 1.43; P = 0.004). DISCUSSION: Following TKA, HCAHPS survey response rate was only 31.22% and completion of the survey was associated with several demographic and postoperative variables. These findings suggest that HCAHPS survey results capture a non-representative fraction of the true TKA patient population. This bias is necessary to consider when using HCAHPS survey results as a metric for quality of healthcare and federal reimbursement rates.

The Clinical Implications of Spontaneous Hemorrhage in Vestibular Schwannomas.

Background Spontaneous hemorrhage into vestibular schwannomas (VSs) is rare and can render more rapid symptom onset and a seemingly poorer prognosis for an otherwise benign pathology. We describe our series of hemorrhagic VS (HVSs) and systematically reviewed the literature to better understand relevant clinical factors and outcomes. Methods Retrospective case review series and systematic review of the literature using PRISMA guidelines. Results Fifty-three patients with HVS met inclusion criteria. Compared with historical data for all VS, patients with HVS had relatively higher rates of perioperative mortality, significant preoperative facial weakness, and harbored relatively larger tumors. Regardless of the extent of resection (EOR), surgery for HVS resulted in significant improvement of facial weakness ( p = 0.041), facial numbness ( p < 0.001), vertigo ( p < 0.001), and headache ( p < 0.001). Patients with facial weakness tended to have larger tumors ( p = 0.058) on average and demonstrated significant improvement after surgery, irrespective of EOR ( p < 0.01). The use of blood-thinning medications did not affect patient health outcome. Histopathology of HVS samples showed an increased number of dilated/ectatic thin-walled vascular channels, reflective of potentially increased vascular permeability and hypervascularity. Conclusion HVS may be an aggressive subgroup of VS, associated with a surprisingly high mortality rate. When features of HVS are identified on imaging, these patients should be treated expeditiously, especially given that facial nerve dysfunction, which is identified in more than half of patients with HVS, appears to be reversible. Overall, this study has significant implications in the management of VS, raising awareness of a small, but highly morbid subgroup.

Impact of race on outcomes and healthcare utilization following spinal fusion for adolescent idiopathic scoliosis.

OBJECTIVES: Racial disparities in spine surgery have been shown to impact surgical management and postoperative complications. However, for adolescent patients with idiopathic scoliosis (AIS) treated by posterior spinal fusion (PSF), the influence of race on postoperative outcomes remains unclear. The aim of the study was to investigate the differences in baseline patient demographics, inpatient management, and postoperative complications for adolescents with AIS undergoing elective, posterior spinal surgery (≥ 4 levels). PATIENTS AND METHODS: The Kids' Inpatient Database year 2012 was queried. Adolescent patients (age 10-17 years old) with AIS undergoing elective, PSF (≥ 4 levels) were selected using the International Classification of Diseases, Ninth Revision, Clinical Modification coding system. Patients were divided into 4 cohorts: Black, White, Hispanic, and Other. Patient demographics, comorbidities, complications, length of hospital stay (LOS), discharge disposition and total cost were recorded. The primary outcome was the rate of intraoperative and postoperative complications and resource utilization after elective PSF intervention. RESULTS: Patient demographics significantly differed between the four cohorts. While age was similar (p = 0.288), the White cohort had a greater proportion of female patients (White: 79.0%; Black: 72.1%; Hispanic: 78.2%; Other: 75.9%, p = 0.006), and the Black cohort had the largest proportion of patients in the 0-25th income quartile (White: 16.1%; Black: 43.3%; Hispanic: 28.0%; Other: 15.3%, p < 0.001). There were significant differences in hospital region (p < 0.001) and bed size (p < 0.001) between the cohorts, with more Hispanic adolescents being treated in the West (White: 21.9%; Black: 8.9%; Hispanic: 40.3%; Other: 29.3%) at small hospitals (White: 14.0%; Black: 13.9%; Hispanic: 16.2%; Other: 7.1%). Baseline comorbidities were similar between the cohorts. The use of blood transfusions was significantly greater in the Black cohort compared to the other racial groups (White: 16.7%; Black: 25.0%; Hispanic: 24.5%; Other: 22.7%, p < 0.001). The number of vertebral levels involved differed significantly between the cohorts (p < 0.001), with the majority of patients having 9-levels or greater involved (White: 80.9%; Black: 81.7%; Hispanic: 84.3%; Other: 67.3%). The rate of complications encountered during admission was greatest in the Other cohort (White: 21.9%; Black: 23.6%; Hispanic: 22.2%; Other: 34.9%, p < 0.001). While LOS was similar between the cohorts (p = 0.702), median total cost of admission was highest for Hispanic patients (White: $49,340 [37,908-65,078]; Black: $47,787 [37,718-64,670]; Hispanic: $54,718 [40,689-69,266]; Other: $54,110 [41,292-71,540], p < 0.001). CONCLUSIONS: Our study suggests that race may not have a significant impact on surgical outcomes after elective posterior spine surgery for adolescent idiopathic scoliosis. Further studies are necessary to corroborate our findings.

Independent Association of Obesity and Nonroutine Discharge Disposition After Elective Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Myelopathy.

OBJECTIVE: The prevalence of obesity continues to rise in the United States at a disparaging rate. Although previous studies have attempted to identify the influence obesity has on short-term outcomes following elective spine surgery, few studies have assessed the impact on discharge disposition following anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM). The aim of this study was to determine whether obesity impacts the hospital management, cost, and discharge disposition after elective ACDF for adult CSM. METHODS: The National Inpatient Sample database was queried using the International Classification of Diseases, 10th revision, Clinical Modification, coding system to identify all (≥18 years) patients with a primary diagnosis of CSM undergoing an elective ACDF for the years 2016 and 2017. Discharge weights were used to estimate national demographics, Elixhauser comorbidities, complications, length of stay, total cost of admission, and discharge disposition. RESULTS: There were 17,385 patients included in the study, of whom 3035 (17.4%) had obesity (no obesity: 14,350; obesity: 3035). The cohort with obesity had a significantly greater proportion of patients with 3 or more comorbidities compared with the cohort with no obesity (no obesity: 28.1% vs. obesity: 43.5%, P < 0.001). The overall complication rates were greater in the cohort with obesity (no obesity: 10.3% vs. obesity: 14.3%, P = 0.003). On average, the cohort with obesity incurred a total cost of admission $1154 greater than the cost of the cohort with no obesity (no obesity: $19,732 ± 11,605 vs. obesity: $20,886 ± 10,883, P = 0.034) and a significantly greater proportion of nonroutine discharges (no obesity: 16.6% vs. obesity: 24.2%, P < 0.001). In multivariate regression analysis, obesity, age, race, health care coverage, hospital bed size, region, comorbidity, and complication rates all were independently associated with nonroutine discharge disposition. CONCLUSIONS: Our study demonstrates that obesity is an independent predictor for nonroutine discharge disposition following elective anterior cervical discectomy and fusion for cervical spondylotic myelopathy.