Predictors of Complication Severity Following Adult Spinal Deformity Surgery: Smoking Rate, Diabetes, and Osteotomy Increase Risk of Severe Adverse Events.

BACKGROUND: Given the physical and economic burden of complications in spine surgery, reducing the prevalence of perioperative adverse events is a primary concern of both patients and health care professionals. This study aims to identify specific perioperative factors predictive of developing varying grades of postoperative complications in adult spinal deformity (ASD) patients, as assessed by the Clavien-Dindo complication classification (Cc) system. METHODS: Surgical ASD patients ≥18 years were identified in the American College of Surgeons' National Surgical Quality Improvement Program from 2005 to 2015. Postoperative complications were stratified by Cc grade severity: minor (I, II, and III) and severe (IV and V). Stepwise regression models generated dataset-specific predictive models for Cc groups. Model internal validation was achieved by bootstrapping and calculating the area under the curve (AUC) of the model. Significance was set at P < 0.05. RESULTS: Included were 3936 patients (59 ± 16 years, 63% women, 29 ± 7 kg/m2) undergoing surgery for ASD (4.4 ± 4.7 levels, 71% posterior approach, 11% anterior, and 18% combined). Overall, 1% of cases were revisions, 39% of procedures involved decompression, 27% osteotomy, and 15% iliac fixation. Additionally, 66% of patients experienced at least 1 complication, 0% of which were Cc grade I, 51% II, 5% III, 43% IV, and 1% V. The final model predicting severe Cc (IV-V) complications yielded an AUC of 75.6% and included male sex, diabetes, increased operative time, central nervous system tumor, osteotomy, cigarette pack-years, anterior decompression, and anterior lumbar interbody fusion. Final models predicting specific Cc grades were created. CONCLUSIONS: Specific predictors of adverse events following ASD-corrective surgery varied for complications of different severities. Multivariate modeling showed smoking rate, osteotomy, diabetes, anterior lumbar interbody fusion, and higher operative time, among other factors, as predictive of severe complications, as classified by the Clavien-Dindo Cc system. These factors can help in the identification of high-risk patients and, consequently, improve preoperative patient counseling. CLINICAL RELEVANCE: The findings of this study provide a foundation for identifying ASD patients at high risk of postoperative complications .

Defining age-adjusted spinopelvic alignment thresholds: should we integrate BMI?

PURPOSE: To develop age- and BMI-adjusted alignment targets to improve patient-specific management and operative treatment outcomes. METHODS: Retrospective review of a single-center stereographic database. ASD patients receiving operative or non-operative treatment, ≥ 18y/o with complete baseline (BL) ODI scores and radiographic parameters (PT, SVA, PILL, TPA) were included. Patients were stratified by age consistent with US-Normative values (norms) of SF-36(< 35, 35-55, 45-54, 55-64, 65-74, ≥ 75y/o), and dichotomized by BMI (Non-Obese < 30; Obese ≥ 30). Linear regression analysis established normative age- and BMI-specific radiographic thresholds, utilizing previously published age-specific US-Normative ODI values converted from SF-36 PCS (Lafage et al.), in conjunction with BL age and BMI means. RESULTS: 486 patients were included (Age: 52.5, Gender: 68.7%F, mean BMI: 26.2, mean ODI: 32.7), 135 of which were obese. Linear regression analysis developed age- and BMI-specific alignment thresholds, indicating PT, SVA, PILL, and TPA to increase with both increased age and increased BMI (all R > 0.5, p < 0.001). For non-obese patients, PT, SVA, PILL, and TPA ranged from 10.0, - 25.8, - 9.0, 3.1 in patients < 35y/o to 27.8, 53.4, 17.7, 25.8 in patients ≥ 75 y/o. Obese patients' PT, SVA, PILL, and TPA ranged from 10.5, - 7.6, - 7.1, 5.8 in patients < 35 y/o to 28.3, 67.0, 19.15, 27.7 in patients ≥ 75y/o. Normative SVA values in obese patients were consistently ≥ 10 mm greater compared to non-obese values, at all ages. CONCLUSION: Significant associations exist between age, BMI, and sagittal alignment. While BMI influenced age-adjusted alignment norms for PT, SVA, PILL, and TPA at all ages, obesity most greatly influenced SVA, with normative values similar to non-obese patients who were 10 years older. Age-adjusted alignment thresholds should take BMI into account, calling for less rigorous alignment objectives in older and obese patients.

Cervical Deformity Correction Fails to Achieve Age-Adjusted Spinopelvic Alignment Targets.

OBJECTIVE: To assess whether surgical cervical deformity (CD) patients meet spinopelvic age-adjusted alignment targets, reciprocal, and lower limb compensation changes. STUDY DESIGN: Retrospective review. METHODS: CD was defined as C2-C7 lordosis >10°, cervical sagittal vertical angle (cSVA) >4 cm, or T1 slope minus cervical lordosis (TS-CL) >20°. Inclusion criteria were age >18 years and undergoing surgical correction with complete baseline and postoperative imaging. Published formulas were used to create age-adjusted alignment target for pelvic tilt (PT), pelvic incidence and lumbar lordosis (PI-LL), sagittal vertical angle (SVA), and lumbar lordosis and thoracic kyphosis (LL-TK). Actual alignment was compared with age-adjusted ideal values. Patients who matched ±10-year thresholds for age-adjusted targets were compared with unmatched cases (under- or overcorrected). RESULTS: A total of 120 CD patients were included (mean age, 55.1 years; 48.4% women; body mass index, 28.8 kg/m2). For PT, only 24.4% of patients matched age-adjusted alignment, 51.1% overcorrected for PT, and 24.4% undercorrected. For PI-LL, only 27.6% of CD patients matched age-adjusted targets, with 49.4% overcorrected and 23% undercorrected postoperatively. Forty percent of patients matched age-adjusted target for SVA, 41.3% overcorrected, and 18.8% undercorrected. CD patients who had worsened in TS-CL or cSVA postoperatively displayed increased TK (-41.1° to -45.3°, P = 1.06). With lower extremity compensation, CD patients decreased in ankle flexion angle postoperatively (6.1°-5.5°, P = 0.036) and trended toward smaller sacrofemoral angle (199.6-195.6 mm, P = 0.286) and knee flexion (2.6° to -1.1°, P = 0.269). CONCLUSIONS: In response to worsening CD postoperatively, patients increased in TK and recruited less lower limb compensation. Almost 75% of CD patients did not meet previously established spinopelvic alignment goals, of whom a subset of patients were actually made worse off in these parameters following surgery. This finding raises the question of whether we should be looking at the entire spine when treating CD.

Bariatric Surgery Lowers Rates of Spinal Symptoms and Spinal Surgery in a Morbidly Obese Population.

STUDY DESIGN: Retrospective analysis of New York State Inpatient Database years 2004-2013. OBJECTIVE: Assess rates of spinal diagnoses and procedures before and after bariatric surgery (BS). SUMMARY OF BACKGROUND DATA: BS for morbid obesity helps address common comorbidity burdens and improves quality of life for patients. The effects of BS on spinal disorders and surgical intervention have yet to be investigated. MATERIALS AND METHODS: Patients included in analysis if they underwent BS and were seen at the hospital before and after this intervention. Spinal conditions and rates of surgery assessed before and after BS using χ 2 tests for categorical variables. Multivariable logistic regression analysis used to compare rates in BS patients to control group of nonoperative morbidly obese patients. Logistic testing controlled for comorbidities, age, biological sex. RESULTS: A total of 73,046 BS patients included (age 67.88±17.66 y, 56.1% female). For regression analysis, 299,504 nonbariatric, morbidly obese patients included (age 53.45±16.52 y, 65.6% female). Overall, rates of spinal symptoms decreased following BS (7.40%-5.14%, P <0.001). Cervical, thoracic, lumbar spine diagnoses rates dropped from 3.28% to 2.99%, 2.91% to 2.57%, and 5.39% to 3.92% (all P <0.001), respectively. Most marked reductions seen in cervical spontaneous compression fractures, cervical disc herniation, thoracic radicular pain, spontaneous lumbar compression fractures, lumbar spinal stenosis, lumbar spondylosis. Controlling for comorbidities, age and sex, obese nonbariatric patients more likely to have encounters associated with several cervical, thoracic or lumbar spinal diagnoses and procedures, especially for cervical spontaneous compression fracture, radicular pain, lumbar spondylosis, lumbar spinal stenosis, posterior procedures. BS significantly lowered comorbidity burden for many specific factors. CONCLUSIONS: BS lowered rates of documented spinal disorders and procedures in a morbidly obese population. These findings provide evidence of additional health benefits following BS, including reduction in health care encounters for spinal disorders and rates of surgical intervention.

Long-Term Risk of Death From Heart Disease Among Breast Cancer Patients.

Background: Most breast cancer patients die of non-cancer causes. The risk of death from heart disease, a leading cause of death, is unknown. The aim of this study is to characterize the long-term risk of fatal heart disease in breast cancer patients. Methods: This retrospective study used the Surveillance, Epidemiology, and End Results (SEER) database. Standard mortality ratios (SMR) were calculated for breast cancer patients diagnosed from 1992 to 2014. Patients were stratified by receipt of radiotherapy and/or chemotherapy, disease laterality, and diagnosis era. Hazard ratios (HRs) and odds ratios (ORs) were calculated to compare the risk of death from heart disease among other breast cancer patients. Results: There were 1,059,048 patients diagnosed with breast cancer from 1992 to 2014, of which 47,872 (4.6%) died from heart disease. The SMR for death from heart disease at 10+ years for patients who received only radiotherapy was 2.92 (95% CI 2.81-3.04, p < 0.001) and in patients who received only chemotherapy was 5.05 (95% CI 4.57-5.55, p < 0.001). There was no statistically significant difference in SMR for death from heart disease for left-sided vs. right-sided disease. At 10+ years, heart disease made up 28% of deaths from non-primary cancer. HRs and ORs showed that the risk of death from heart disease was highest in patients older than 70 years of age and with longer follow-up. Conclusion: The risk of fatal heart disease was highest in older breast cancer patients with longer follow-up (i.e., >5-10 years) and who received chemotherapy. These patients should be referred to cardio-oncology clinics to mitigate this risk.

Predictive Analytics for Determining Extended Operative Time in Corrective Adult Spinal Deformity Surgery.

BACKGROUND: More sophisticated surgical techniques for correcting adult spinal deformity (ASD) have increased operative times, adding to physiologic stress on patients and increased complication incidence. This study aims to determine factors associated with operative time using a statistical learning algorithm. METHODS: Retrospective review of a prospective multicenter database containing 837 patients undergoing long spinal fusions for ASD. Conditional inference decision trees identified factors associated with skin-to-skin operative time and cutoff points at which factors have a global effect. A conditional variable-importance table was constructed based on a nonreplacement sampling set of 2000 conditional inference trees. Means comparison for the top 15 variables at their respective significant cutoffs indicated effect sizes. RESULTS: Included: 544 surgical ASD patients (mean age: 58.0 years; fusion length 11.3 levels; operative time: 378 minutes). The strongest predictor for operative time was institution/surgeon. Center/surgeons, grouped by decision tree hierarchy, a and b were, on average, 2 hours faster than center/surgeons c-f, who were 43 minutes faster than centers g-j, all P < 0.001. The next most important predictors were, in order, approach (combined vs posterior increases time by 139 minutes, P < 0.001), levels fused (<4 vs 5-9 increased time by 68 minutes, P < 0.050; 5-9 vs < 10 increased time by 47 minutes, P < 0.001), age (age <50 years increases time by 57 minutes, P < 0.001), and patient frailty (score <1.54 increases time by 65 minutes, P < 0.001). Surgical techniques, such as three-column osteotomies (35 minutes), interbody device (45 minutes), and decompression (48 minutes), also increased operative time. Both minor and major complications correlated with <66 minutes of increased operative time. Increased operative time also correlated with increased hospital length of stay (LOS), increased estimated intraoperative blood loss (EBL), and inferior 2-year Oswestry Disability Index (ODI) scores. CONCLUSIONS: Procedure location and specific surgeon are the most important factors determining operative time, accounting for operative time increases <2 hours. Surgical approach and number of levels fused were also associated with longer operative times, respectively. Extended operative time correlated with longer LOS, higher EBL, and inferior 2-y ODI outcomes. CLINICAL RELEVANCE: We further identified the poor outcomes associated with extended operative time during surgical correction of ASD, and attributed the useful predictors of time spent in the operating room, including site, surgeon, surgical approach, and the number of levels fused.

Predictive model for achieving good clinical and radiographic outcomes at one-year following surgical correction of adult cervical deformity.

BACKGROUND: For cervical deformity (CD) surgery, goals include realignment, improved patient quality of life, and improved clinical outcomes. There is limited research identifying patients most likely to achieve all three. OBJECTIVE: The objective is to create a model predicting good 1-year postoperative realignment, quality of life, and clinical outcomes following CD surgery using baseline demographic, clinical, and radiographic factors. METHODS: Retrospective review of a multicenter CD database. CD patients were defined as having one of the following radiographic criteria: Cervical sagittal vertical axis (cSVA) >4 cm, cervical kyphosis/scoliosis >10°° or chin-brow vertical angle >25°. The outcome assessed was whether a patient achieved both a good radiographic and clinical outcome. The primary analysis was stepwise regression models which generated a dataset-specific prediction model for achieving a good radiographic and clinical outcome. Model internal validation was achieved by bootstrapping and calculating the area under the curve (AUC) of the final model with 95% confidence intervals. RESULTS: Seventy-three CD patients were included (61.8 years, 58.9% F). The final model predicting the achievement of a good overall outcome (radiographic and clinical) yielded an AUC of 73.5% and included the following baseline demographic, clinical, and radiographic factors: mild-moderate myelopathy (Modified Japanese Orthopedic Association >12), no pedicle subtraction osteotomy, no prior cervical spine surgery, posterior lowest instrumented vertebra (LIV) at T1 or above, thoracic kyphosis >33°°, T1 slope <16 and cSVA <20 mm. CONCLUSIONS: Achievement of a positive outcome in radiographic and clinical outcomes following surgical correction of CD can be predicted with high accuracy using a combination of demographic, clinical, radiographic, and surgical factors, with the top factors being baseline cSVA <20 mm, no prior cervical surgery, and posterior LIV at T1 or above.

Risk-benefit assessment of major versus minor osteotomies for flexible and rigid cervical deformity correction.

INTRODUCTION: Osteotomies are commonly performed to correct sagittal malalignment in cervical deformity (CD). However, the risks and benefits of performing a major osteotomy for cervical deformity correction have been understudied. The objective of this retrospective cohort study was to investigate the risks and benefits of performing a major osteotomy for CD correction. METHODS: Patients stratified based on major osteotomy (MAJ) or minor (MIN). Independent t-tests and Chi-squared tests were used to assess differences between MAJ and MIN. A sub-analysis compared patients with flexible versus rigid CL. RESULTS: 137 CD patients were included (62 years, 65% F). 19.0% CD patients underwent a MAJ osteotomy. After propensity score matching for cSVA, 52 patients were included. About 19.0% CD patients underwent a MAJ osteotomy. MAJ patients had more minor complications (P = 0.045), despite similar surgical outcomes as MIN. At 3M, MAJ and MIN patients had similar NDI, mJOA, and EQ5D scores, however by 1 year, MAJ patients reached MCID for NDI less than MIN patients (P = 0.003). MAJ patients with rigid deformities had higher rates of complications (79% vs. 29%, P = 0.056) and were less likely to show improvement in NDI at 1 year (0.95 vs. 0.54, P = 0.027). Both groups had similar sagittal realignment at 1 year (all P > 0.05). CONCLUSIONS: Cervical deformity patients who underwent a major osteotomy had similar clinical outcomes at 3-months but worse outcomes at 1-year as compared to minor osteotomies, likely due to differences in baseline deformity. Patients with rigid deformities who underwent a major osteotomy had higher complication rates and worse clinical improvement despite similar realignment at 1 year.

The Epidemiology of Lung Metastases.

Introduction: Lung metastasis is usually associated with poor outcomes in cancer patients. This study was performed to characterize and analyze the population of patients with de novo (synchronous) lung metastases using the Surveillance, Epidemiology and End Results (SEER) database. Materials and Methods: Baseline characteristics of lung metastasis patients were obtained from SEER case listings. Incidence rates and counts of synchronous lung metastasis were also obtained using the SEER*Stat software. Survival outcomes were analyzed using univariate and multivariable Cox regressions, controlling for confounders. An alpha threshold of 0.05 was used for statistical significance and p-values were subject to correction for multiple comparisons. Results: The age-adjusted incidence rate of synchronous lung metastasis was 17.92 per 100,000 between 2010 and 2015. Synchronous lung metastases most commonly arose from primary lung cancers, colorectal cancers, kidney cancers, pancreatic cancers and breast cancers. During this time period, 4% of all cancer cases presented with synchronous lung metastasis. The percentage of patients presenting with synchronous lung metastasis ranged from 0.5% of all prostate cancers to 13% of all primary lung cancers. The percentage of all cancer cases presenting with synchronous lung metastasis increased over time. De novo metastatic patients with lung metastases had worse overall survival [hazard ratio = 1.22 (1.21-1.23), p < 0.001] compared to those with only extrapulmonary metastases, controlling for potential confounders. Conclusions: Synchronous lung metastasis occurs frequently and is an independent predictors of poor patient outcomes. As treatment for lung metastases becomes more complicated, patients with synchronous lung metastasis represent a high-risk population.

Improvement in some Ames-ISSG cervical deformity classification modifier grades may correlate with clinical improvement.

This retrospective cohort study describes adult cervical deformity(ACD) patients with Ames-ACD classification at baseline(BL) and 1-year post-operatively and assesses the relationship of improvement in Ames modifiers with clinical outcomes. Patients ≥ 18yrs with BL and post-op(1-year) radiographs were included. Patients were categorized with Ames classification by primary deformity descriptors (C = cervical; CT = cervicothoracic junction; T = thoracic; S = coronal) and alignment/myelopathy modifiers(C2-C7 Sagittal Vertical Axis[cSVA], T1 Slope-Cervical Lordosis[TS-CL], Horizontal Gaze[Horiz], mJOA). Univariate analysis evaluated demographics, clinical intervention, and Ames deformity descriptor. Patients were evaluated for radiographic improvement by Ames classification and reaching Minimal Clinically Important Differences(MCID) for mJOA, Neck Disability Index(NDI), and EuroQuol-5D(EQ5D). A total of 73 patients were categorized: C = 41(56.2%), CT = 18(24.7%), T = 9(12.3%), S = 5(6.8%). By Ames modifier 1-year improvement, 13(17.8%) improved in mJOA, 26(35.6%) in cSVA grade, 19(26.0%) in Horiz, and 15(20.5%) in TS-CL. The overall proportion of patients without severe Ames modifier grades at 1-year was as follows: 100% cSVA, 27.4% TS-CL, 67.1% Horiz, 69.9% mJOA. 1-year post-operatively, severe myelopathy(mJOA = 3) prevalence differed between Ames-ACD descriptors (C = 26.3%, CT = 15.4%, T = 0.0%, S = 0.0%, p = 0.033). Improvement in mJOA modifier correlated with reaching 1-year NDI MCID in the overall cohort (r = 0.354,p = 0.002). For C descriptors, cSVA improvement correlated with reaching 1-year NDI MCID (r = 0.387,p = 0.016). Improvement in more than one radiographic Ames modifier correlated with reaching 1-year mJOA MCID (r = 0.344,p = 0.003) and with reaching more than one MCID for mJOA, NDI, and EQ-5D (r = 0.272,p = 0.020). In conclusion, improvements in radiographic Ames modifier grades correlated with improvement in 1-year postoperative clinical outcomes. Although limited in scope, this analysis suggests the Ames-ACD classification may describe cervical deformity patients' alignment and outcomes at 1-year.

Effect of age-adjusted alignment goals and distal inclination angle on the fate of distal junctional kyphosis in cervical deformity surgery.

BACKGROUND: Age-adjusted alignment targets in the context of distal junctional kyphosis (DJK) development have yet to be investigated. Our aim was to assess age-adjusted alignment targets, reciprocal changes, and role of lowest instrumented level orientation in DJK development in cervical deformity (CD) patients. METHODS: CD patients were evaluated based on lowest fused level: cervical (C7 or above), upper thoracic (UT: T1-T6), and lower thoracic (LT: T7-T12). Age-adjusted alignment targets were calculated using published formulas for sagittal vertical axis (SVA), pelvic incidence-lumbar lordosis (PI-LL), pelvic tilt (PT), T1 pelvic angle (TPA), and LL-thoracic kyphosis (TK). Outcome measures were cervical and global alignment parameters: Cervical SVA (cSVA), cervical lordosis, C2 slope, C2-T3 angle, C2-T3 SVA, TS-CL, PI-LL, PT, and SVA. Subanalysis matched baseline PI to assess age-adjusted alignment between DJK and non-DJK. RESULTS: Seventy-six CD patients included. By 1Y, 20 patients developed DJK. Non-DJK patients had 27% cervical lowest instrumented vertebra (LIV), 68% UT, and 5% LT. DJK patients had 25% cervical, 50% UT, and 25% LT. There were no baseline or 1Y differences for PI, PI-LL, SVA, TPA, or PT for actual and age-adjusted targets. DJK patients had worse baseline cSVA and more severe 1Y cSVA, C2-T3 SVA, and C2 slope (P < 0.05). The distribution of over/under corrected patients and the offset between actual and ideal alignment for SVA, PT, TPA, PI-LL, and LL-TK were similar between DJK and non-DJK patients. DJK patients requiring reoperation had worse postoperative changes in all cervical parameters and trended toward larger offsets for global parameters. CONCLUSION: CD patients with severe baseline malalignment went on to develop postoperative DJK. Age-adjusted alignment targets did not capture differences in these populations, suggesting the need for cervical-specific goals.

Pelvic Incidence Affects Age-adjusted Alignment Outcomes in a Population of Adult Spinal Deformity.

STUDY DESIGN: A single-center retrospective cohort study. OBJECTIVE: The objective of this study was to assess the effects of patient height and pelvic incidence (PI) on age-adjusted alignment outcomes of surgical adult spinal deformity (ASD) patients. SUMMARY OF BACKGROUND DATA: Patient height and PI have yet to be evaluated for their individual effects on achieving age-adjusted alignment targets. METHODS: Surgical ASD patients were grouped by percentile (low: <25th; normative: 25th-75th; high: >75th) for height and PI. Correction groups were generated at postoperative follow-up for actual alignment compared with age-adjusted ideal values for pelvic tilt (PT), pelvic incidence minus lumbar lordosis mismatch (PI-LL), and sagittal vertical axis, and PI-adjusted ideal alignment values for sacral slope (SS), as derived from clinically relevant formulas. Means comparison tests assessed differences in rates of matching ideal alignment (±10 y threshold for age-adjusted targets; -7 to 5 degrees measured minus ideal for SS) across height and PI groups. RESULTS: Breakdown of all included 198 patients by PI group: low (25%, 38±11 degrees), normative (50%, 57±5 degrees), high (25%, 75±7 degrees). Breakdown of patient height groups: low (25%, 1.52±0.04 m), normative (50% 1.64±0.05 m), and high (25%, 1.79±0.06 m). Overall, 29% of patients met postoperative age-adjusted alignment targets for PT, 23% for PI-LL, and 25% for sagittal vertical axis. Overall, 26% of patients met PI-adjusted SS alignment. There were no differences across patient height groups in rates of achieving adjusted alignment target (all P>0.05). Patients with high PI reached age-adjusted ideal alignment for PT at a lower rate (16%) than patients with normative (33%) or low PI (33%, P=0.056). Of patients that matched at least 1 ideal alignment target, those with high PI showed inferior preoperative to postoperative changes in EuroQol 5-dimension questionnaire as compared with normative and low PI patients (P=0.015). CONCLUSIONS: Patients with high PI reached ideal postoperative age-adjusted PT alignment at a lower rate than patients with normative and low PI. Height had no impact on postoperative age-adjusted alignment outcomes. Current postoperative ideal alignment targets may warrant an adjustment to account for PI.

Complication Risk in Primary and Revision Minimally Invasive Lumbar Interbody Fusion: A Comparable Alternative to Conventional Open Techniques?

STUDY DESIGN: Retrospective cohort study of prospective patients undergoing minimally invasive lumbar fusion at a single academic institution. OBJECTIVE: To assess differences in perioperative outcomes between primary and revision MIS (minimally invasive surgical) lumbar interbody fusion patients and compare with those undergoing corresponding open procedures. METHODS: Patients ≥18 years old undergoing lumbar interbody fusion were grouped by surgical technique: MIS or open. Patients within each group were propensity score matched for comorbidities and levels fused. Patient demographics, surgical factors, and perioperative complication incidences were compared between primary and revision cases using means comparison tests, as appropriate. RESULTS: Of the 214 lumbar interbody fusion patients included after propensity score matching, 44 (21%) cases were MIS, and 170 (79%) were open. For MIS patients, there were no significant differences between primary and revision cases in estimated blood loss (EBL; 344 vs 299 cm3, P = .682); however, primary cases had longer operative times (301 vs 246 minutes, P = .029). There were no differences in length of stay (LOS), intensive care unit LOS, readmission, and intraoperative or postoperative complications (all P > .05). For open patients, there were no differences between primary and revision cases in EBL (P > .05), although revisions had longer operative times (331 vs 278 minutes, P = .018) and more postoperative complications (61.7% vs 23.8%, P < .001). MIS revision procedures were shorter than open revisions (182 vs 213 minutes, P = .197) with significantly less EBL (294 vs 965 cm3, P < .001), shorter inpatient and intensive care unit LOS, and fewer postoperative complications (all P < .05). CONCLUSIONS: Clinical outcomes of revision MIS lumbar interbody fusion were similar to those of primary surgery. Additionally, MIS techniques were associated with less EBL, shorter LOS, and fewer perioperative complications than corresponding open revisions.

Ossification of the Posterior Longitudinal Ligament in Cervical Spine Cases Trends in Surgical Treatments and Outcomes in the US from 2005 to 2013.

BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) is characterized by ectopic bone formation within the ligament and can elicit cervical spinal canal stenosis. Surgical treatment for OPLL is debated in the literature. This study examined nationwide data to estimate the prevalence of cervical OPLL (C-OPLL) and investigated trends in surgical treatment and outcomes. METHODS: A retrospective cross-sectional study was conducted of the National Inpatient Sample (NIS) database for patients with a diagnosis code for C-OPLL (ICD-9-CM 723.7) from 2005 to 2013. NIS supplied hospital- and yearadjusted weights allowed for accurate assessment of prevalence. Descriptive statistics assessed patient demographics, comorbidities, surgical factors, and complications. Trends were analyzed using chi-squared, ANOVA, and independent sample t-tests. RESULTS: A total of 4,601 C-OPLL discharges were identified (56.7 years, 43% female). The prevalence of C-OPLL has increased from 0.7/100,000 in 2005 to 2.1/100,000 in 2013. Among hospitalized C-OPLL patients, 89.1% underwent surgery, with 62.1% undergoing an anterior-only (A) approach, 21.5% posterior-only (P), and 16.4% combined (AP). Rates of anterior- and decompression-only surgeries have declined since 2005, from 67.5% to 44.4% and 21.6% to 14.8%, respectively (p < 0.001 for both). Corpectomy rates have dramatically increased, from 3.6% to 27.2% (p < 0.001). Overall complication rates have increased 2.5% since 2005 (p < 0.001) with higher rates of dysphagia (0.7%) and dural tears (5.6%) associated with A-only surgeries (p < 0.001 for both). The overall mortality rate was 0.8%, with P surgery associated with the highest rate, 1.6% (p = 0.002). CONCLUSIONS: The rate of hospitalization for C-OPLL has increased over the last decade as have morbidity rates for C-OPLL discharges. Anterior-only surgeries were associated with higher complication rates. Surgical rates have remained constantsince 2005, butrates of anterior-only and decompression-only procedures have decreased in favor of posterior-only and combined-approach surgeries.

Epidemiology of liver metastases.

AIMS: The objectives of this study were to (1) characterize the epidemiology of liver metastases at the time of primary cancer diagnosis (synchronous liver metastases), (2) characterize the incidence trends of synchronous liver metastases from 2010-2015 and (3) assess survival of patients with synchronous liver metastases. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015 was queried to obtain cases of patients with liver metastases at the time of primary cancer diagnosis. The primary cancers with an incidence rate of liver metastasis >0.1 are presented in this analysis. RESULTS: Among 2.4 million cancer patients, 5.14 % of cancer patients presented with synchronous liver metastases. The most common primary site was breast cancers for younger women (ages 20-50), and colorectal cancers for younger men. As patients get older, a more heterogenous population of the top cancers with liver metastases emerges including esophageal, stomach, small intestine, melanoma, and bladder cancer in addition to the large proportion of lung, pancreatic, and colorectal cancers. The 1-year survival of all patients with liver metastases was 15.1 %, compared to 24.0 % in those with non-hepatic metastases. Regression analysis showed that the presence of liver metastasis was associated with reduced survival, particularly in patients with cancers of the testis, prostate, breast, and anus, and in those with melanoma. CONCLUSIONS: The most common primary sites for patients with liver metastases varied based on age at diagnosis. Survival for patients with liver metastasis was significantly decreased as compared to patients without liver metastasis.

ODI Cannot Account for All Variation in PROMIS Scores in Patients With Thoracolumbar Disorders.

STUDY DESIGN: Retrospective review of single institution. OBJECTIVE: To assess the relationship between Patient-Reported Outcomes Measurement Information System (PROMIS) and Oswestry Disability Index (ODI) scores in thoracolumbar patients. METHODS: Included: Patients ≥18 years with a thoracolumbar spine condition (spinal stenosis, disc herniation, low back pain, disc degeneration, spondylolysis). Bivariate correlations assessed the linear relationships between ODI and PROMIS (Physical Function, Pain Intensity, and Pain Interference). Correlation cutoffs assessed patients with high and low correlation between ODI and PROMIS. Linear regression predicted the relationship of ODI to PROMIS. RESULTS: A total of 206 patients (age 53.7 ± 16.6 years, 49.5% female) were included. ODI correlated with PROMIS Physical Function (r = -0.763, P < .001), Pain Interference (r = 0.800, P < .001), and Pain Intensity (r = 0.706, P < .001). ODI strongly predicted PROMIS for Physical Function (R 2 = 0.58, P < .001), Pain Intensity (R 2 = 0.50, P < .001), and Pain Interference (R 2 = 0.64, P < .001); however, there is variability in PROMIS that ODI cannot account for. ODI questions about sitting and sleeping were weakly correlated across the 3 PROMIS domains. Linear regression showed overall ODI score as accounting for 58.3% (R 2 = 0.583) of the variance in PROMIS Physical Function, 63.9% (R 2 = 0.639) of the variance in Pain Interference score, and 49.9% (R 2 = 0.499) of the variance in Pain Intensity score. CONCLUSIONS: There is a large amount of variability with PROMIS that cannot be accounted for with ODI. ODI questions regarding walking, social life, and lifting ability correlate strongly with PROMIS while sitting, standing, and sleeping do not. These results reinforce the utility of PROMIS as a valid assessment for low back disability, while indicating the need for further evaluation of the factors responsible for variation between PROMIS and ODI.

Epidemiology of synchronous brain metastases.

BACKGROUND: The objectives of this study were to characterize (1) epidemiology of brain metastases at the time of primary cancer diagnosis, (2) incidence and trends of synchronous brain metastases from 2010 to 2015, and (3) overall survival (OS) of patients with synchronous brain metastases. METHODS: A total of 42 047 patients with synchronous brain metastases from 2010 to 2015 were identified from the Surveillance, Epidemiology, and End Results database. Descriptive analysis was utilized to analyze demographics and incidence. The Kaplan-Meier method and a Cox proportional hazards model were utilized to evaluate potential prognostic factors for OS. RESULTS: The majority of patients were diagnosed from age older than 50 (91.9%). Common primary sites included lung (80%), melanoma (3.8%), breast (3.7%), and kidney/renal pelvis (3.0%). Among pediatric patients, common primaries included kidney/renal pelvis and melanomas. The incidence was roughly 7.3 persons/100 000. Synchronous brain metastases were associated with significantly poorer OS compared to extracranial metastases alone (hazard ratio [HR] =1.56; 95% CI: 1.54-1.58; P < .001). Among patients with brain metastases, male gender (HR = 1.60 vs 1.52), age older than 65 years (HR = 1.60 vs 1.46), synchronous liver, bone, or lung metastases (HR = 1.61 vs 1.49), and earlier year of diagnosis (HR = 0.98 for each year following 2010) were associated with significantly poorer OS. CONCLUSIONS: The vast majority of brain metastases are from lung primaries. Synchronous brain metastases are associated with poorer OS compared to extracranial metastases alone.

Probability of severe frailty development among operative and nonoperative adult spinal deformity patients: an actuarial survivorship analysis over a 3-year period.

BACKGROUND: Little is known of how frailty, a dynamic measure of physiological age, progresses relative to age or disability status. Operative treatment of adult spinal deformity (ASD) may play a role in frailty remediation and maintenance. PURPOSE: Compare frailty status, severe frailty development, and factors influencing severe frailty development among ASD patients undergoing operative or nonoperative treatment. DESIGN: Retrospective review with maximum follow-up of 3 years. SETTING: Prospective, multicenter, ASD database. PARTICIPANTS: Patients were consecutively enrolled from 13 participating centers. INCLUSION CRITERIA: ≥18 years undergoing either operative or nonoperative treatment for ASD, exclusion criteria: spinal deformity of neuromuscular etiology, presence of active infection, or malignancy. The mean age of the participants analyzed were 54.9 for the operative cohort and 55.0 for the nonoperative cohort. OUTCOMES MEASURES: Frailty status, severe frailty development, and factors influencing severe frailty development. METHODS: ASD patients (coronal scoliosis ≥20°, sagittal vertical axis (SVA) ≥5 cm, Pelvic Tilt (PT) ≥25°, or thoracic kyphosis ≥60°) >18 y/o, with Base Line (BL) frailty scores were included. Frailty was scored from 0 to 1 (not frail: <0.3, frail 0.3-0.5, severe frailty >0.5) through the use of ASD-frailty index (FI) which has been validated using the International Spine Study Group (ISSG) ASD database, European Spine Study Group ASD database, and the Scoli-RISK-1 Patient Database. The ISSG is funded through research grants from DePuy Synthes and individual donations and supported the current work. Operative (Op) and Nonoperative (Non-Op) patients were propensity matched. T-tests compared frailty among treatment groups and BL, 1, 2, and ≥3 years. An actuarial Kaplan-Meier survivorship analysis with log-rank (Mantel-Cox) test, adjusting for patients lost to follow-up, determined probability of severe frailty development. Multivariate Cox Regressions gauged the effect of sagittal malalignment, patient and surgical details on severe frailty development. RESULTS: The analysis includes 472 patients (236 Op, 236 Non-Op) selected by propensity score matching from a cohort of 1,172. Demographics and comorbidities were similar between groups (p>.05). Op exhibited decreased frailty at all follow-up intervals compared with BL (BL: 0.22 vs Y1: 0.18; Y2: 0.16; Y3: 0.15, all p<.001). Non-Op displayed similar frailty from BL to 2Y follow up, and increased frailty at 3Y follow up (0.23 vs 0.25, p=.014). Compared with Non-Op, Op had lower frailty at 1Y (0.18 vs 0.24), 2Y (0.16 vs 0.23), and 3Y (0.15 vs 0.25; all p<.001). Cumulative probability of maintaining nonsevere frailty was (Op: 97.7%, Non-Op: 94.5%) at 1Y, (Op: 95.1%, Non-Op: 90.4%) at 2Y, and (Op: 95.1%, Non-Op: 89.1%) at ≥3Y, (p=.018). Among all patients, baseline depression (hazard ratio: 2.688[1.172-6.167], p=.020), Numeric Rating Scale (NRS) back pain scores (HR: 1.247[1.012-1.537], p=.039), and nonoperative treatment (HR: 2.785[1.167-6.659], p=.021) predicted severe frailty development with having a HR>1.0 and p value<.05. Among operative patients, 6-week postoperative residual SVA malalignment (SRS-Schwab SVA+modifier) (HR: 15.034[1.922-116.940], p=.010) predicted severe frailty development indicated by having a HR>1.0 and p value <.05. CONCLUSIONS: Non-Op patients were more likely to develop severe frailty, and at a quicker rate. Baseline depression, increased NRS back pain scores, nonoperative treatment, and postoperative sagittal malalignment at 6-week follow-up significantly predicted severe frailty development. Operative intervention and postoperative sagittal balance appear to play significant roles in frailty remediation and maintenance in ASD patients. Frailty is one factor, in a multifactorial conservation, that may be considered when determining operative or nonoperative values for ASD patients. Operating before the onset of severe frailty, may result in a lower complication risk and better long-term clinical outcomes.

Long-term causes of death among pediatric patients with cancer.

BACKGROUND: The objectives of this study were to characterize the risk of death (1) from the primary cancer vs competing cause of death; and (2) from various causes of death vs the general poplation. The relative risk of death after a pediatric cancer diagnosis versus the general population and the risk of death from a primary cancer diagnosis versus competing causes of death. METHODS: This retrospective, population-based study used the Surveillance, Epidemiology, and End Results database (1980-2015) and included patients aged 0 to 19 years at the time of diagnosis. Observed deaths were calculated; the risk of death versus the general population was assessed with standardized mortality ratios (SMRs). Competing risk models for the cause of death were performed. RESULTS: There were 58,356 patients who were diagnosed, and the mortality rate was 22.8%. To assess causes of death, 6996 patients who died during the study period were included (45,580 total person-years at risk): 5128 (73%) died of their primary cancer, and 1868 (27%) died of a competing cause. Among all patients, the rate of death from the index cancer was higher than the rate of death from another cause within the first 5 years after diagnosis. The risk of death from a nonprimary cancer began to supersede the rate of death from the primary cancer 10 years after diagnosis for patients with germ cell tumors, lymphomas, and sarcomas. SMRs for the primary cancer were highest within the first 5 years after diagnosis for all cancers (SMRs, 100-50,000; P < .0001). The risk of death from competing causes (heart disease, suicide, and sepsis) was elevated (SMR, >100; P < .001). The risk of dying of heart disease was high, especially for patients with astrocytomas (SMR, 47.84; 95% confidence interval [CI], 27.87-76.59) and neuroblastomas (SMR, 98.59; 95% CI, 47.28-181.32). The risk of dying of suicide was high in most patients, particularly for those with osteosarcomas (SMR, 111.40; 95% CI, 2.82-620.69), Hodgkin lymphomas (SMR, 62.35; 95% CI, 34.89-102.83), and gonadal germ cell tumors (SMR, 28.97; 95% CI, 12.51-57.09). CONCLUSIONS: The cause of death for patients with gonadal germ cell tumors, lymphomas, and sarcomas is more commonly a secondary cancer or noncancerous cause than the primary disease; their risk of death from competing causes (heart disease, suicide, and sepsis) rises throughout life.

Hospital-acquired conditions occur more frequently in elective spine surgery than for other common elective surgical procedures.

Hospital-acquired conditions (HACs) have been the focus of recent initiatives by the Centers for Medicare and Medicaid Services in an effort to improve patient safety and outcomes. Spine surgery can be complex and may carry significant comorbidity burden, including so called "never events." The objective was to determine the rates of common HACs that occur within 30-days post-operatively for elective spine surgeries and compare them to other common surgical procedures. Patients: >18 y/o undergoing elective spine surgery were identified in the American College of Surgeons' NSQIP database from 2005 to 2013. Patients were stratified by whether they experienced >1 HAC, then compared to those undergoing other procedures including bariatric surgery, THA and TKA. Of the 90,551 spine surgery patients, 3021 (3.3%) developed at least one HAC. SSI was the most common (1.4%), followed by UTI (1.3%), and VTE (0.8%). Rates of HACs in spine surgery were significantly higher than other elective procedures including bariatric surgery (2.8%) and THA (2.8%) (both p < 0.001). Spine surgery and TKA patients had similar rates of HACs(3.3% vs 3.4%, p = 0.287), though spine patients experienced higher rates of SSI (1.4%vs0.8%, p < 0.001) and UTI (1.3%vs1.1%, p < 0.001) but lower rates of VTE (0.8%vs1.6%, p < 0.001). Spine surgery patients had lower rates of HACs overall (3.3%vs5.9%) when compared to cardiothoracic surgery patients (p < 0.001). When compared to other surgery types, spine procedures were associated with higher HACs than bariatric surgery patients and knee and hip arthroplasties overall but lower HAC rates than patients undergoing cardiothoracic surgery.