Atlantoaxial dislocation with congenital "sandwich fusion" in the craniovertebral junction: a retrospective case series of 70 patients.

BACKGROUND: In the setting of congenital C1 occipitalization and C2-3 fusion, significant strain is placed on the atlantoaxial joint. Vertebral fusion both above and below the atlantoaxial joint (i.e., a "sandwich") creates substantial instability. We retrospectively report on a case series of "sandwich fusion" atlantoaxial dislocation (AAD), describing the associated clinical characteristics and detailing surgical treatment. To the best of our knowledge, the present study is the largest investigation to date of this congenital subgroup of AAD. METHODS: Seventy consecutive patients with sandwich fusion AAD, from one senior surgeon, were retrospectively reviewed. The clinical features and the surgical treatment results were assessed using descriptive statistics. No funding sources or potential conflict of interest-associated biases exist. RESULTS: The mean patient age was 42.2 years (range: 5-77 years); 36 patients were male, and 34 were female. Fifty-eight patients (82.9%) had myelopathy, with Japanese Orthopaedic Association (JOA) scores ranging 4-16 (mean: 12.9). Cranial neuropathy was involved in 10 cases (14.3%). The most common presentation age group was 31 to 40 years (24 cases, 34.3%). Radiological findings revealed brainstem and/or cervical-medullar compression (58 cases, 82.9%), syringomyelia (16 cases, 22.9%), Chiari malformation (12 cases, 17.1%), cervical spinal stenosis (10 cases, 14.3%), high scapula deformity (1 case, 1.4%), os odontoideum (1 case, 1.4%), and dysplasia of the atlas (1 case, 1.4%). Computed tomography angiography was performed in 27 cases, and vertebral artery (VA) anomalies were identified in 14 cases (51.9%). All 70 patients underwent surgical treatment, without spinal cord or VA injury. Four patients (5.7%) suffered complications, including 1 wound infection, 1 screw loosening, and 2 cases of bulbar paralysis. In the 58 patients with myelopathy, the mean JOA score increased from 12.9 to 14.5. The average follow-up time was 50.5 months (range: 24-120 months). All 70 cases achieved solid atlantoaxial fusion at the final follow-up. CONCLUSIONS: Sandwich fusion AAD, a unique subgroup of AAD, has distinctive clinical features and associated malformations such as cervical-medullar compression, syringomyelia, and VA anomalies. Surgical treatment of AAD was associated with myelopathy improvement and minimal complication occurrence.

Correction to: Prior bariatric surgery lowers complication rates following spine surgery in obese patients.

The AHRQ (Agency for Healthcare Research and Quality) has requested the correction of the result Tables 1-3 of this study: All stated numbers below 10 shall be modified to read "<10" instead.

Cluster analysis describes constellations of cardiac anomalies presenting in spinal anomaly patients.

BACKGROUND: Cardiac anomalies are prevalent in patients with bony spinal anomalies. Prior studies evaluating incidences of bony congenital anomalies of the spine are limited. The Kids' Inpatient Database (KID) yields national discharge estimates of rare pediatric conditions like congenital disorders. This study utilized cluster analysis to study patterns of concurrent vertebral anomalies, anal atresia, cardiac malformations, trachea-esophageal fistula, renal dysplasia, and limb anomalies (VACTERL anomalies) co-occurring in patients with spinal congenital anomalies. METHODS: Retrospective review of KID 2003-2012. KID-supplied hospital- and year-adjusted weights allowed for incidence assessment of bony spinal anomalies and cardiac, gastrointestinal, urinary anomalies of VACTERL. K-means clustering assessed relationships between most frequent anomalies within bony spinal anomaly discharges; k set to n - 1(n = first incidence of significant drop/little gain in sum of square errors within clusters). RESULTS: There were 12,039,432 KID patients 0-20 years. Incidence per 100,000 discharges: 2.5 congenital fusion of spine, 10.4 hemivertebra, 7.0 missing vertebra. The most common anomalies co-occurring with bony vertebral malformations were atrial septal defect (ASD 12.3%), large intestinal atresia (LIA 11.8%), and patent ductus arteriosus (PDA 10.4%). Top congenital cardiac anomalies in vertebral anomaly patients were ASD, PDA, and ventricular septal defect (VSD); all three anomalies co-occur at 6.6% rate in this vertebral anomaly population. Cluster analysis revealed that of bony anomaly discharges, 55.9% of those with PDA had ASD, 34.2% with VSD had PDA, 22.9% with LIA had ASD, 37.2% with ureter obstruction had LIA, and 35.5% with renal dysplasia had LIA. CONCLUSIONS: In vertebral anomaly patients, the most common co-occurring congenital anomalies were cardiac, renal, and gastrointestinal. Top congenital cardiac anomalies in vertebral anomaly patients were ASD, PDA, and VSD. VACTERL patients with vertebral anomalies commonly presented alongside cardiac and renal anomalies.

Prior bariatric surgery lowers complication rates following spine surgery in obese patients.

BACKGROUND: Bariatric surgery (BS) is an increasingly common treatment for morbid obesity that has the potential to effect bone and mineral metabolism. The effect of prior BS on spine surgery outcomes has not been well established. The aim of this study was to assess differences in complication rates following spinal surgery for patients with and without a history of BS. METHODS: Retrospective analysis of the prospectively collected New York State Inpatient Database (NYSID) years 2004-2013. BS patients and morbidly obese patients (non-BS) were divided into cervical and thoracolumbar surgical groups and propensity score matched for age, gender, and invasiveness and complications compared. RESULTS: One thousand nine hundred thirty-nine spine surgery patients with a history of BS were compared to 1625 non-BS spine surgery patients. The average time from bariatric surgery to spine surgery is 2.95 years. After propensity score matching, 740 BS patients were compared to 740 non-BS patients undergoing thoracolumbar surgery, with similar comorbidity rates. The overall complication rate for BS thoracolumbar patients was lower than non-BS (45.8% vs 58.1%, P < 0.001), with lower rates of device-related (6.1% vs 23.2%, P < 0.001), DVT (1.2% vs 2.7%, P = 0.039), and hematomas (1.5% vs 4.5%, P < 0.001). Neurologic complications were similar between BS patients and non-BS patients (2.3% vs 2.7%, P = 0.62). For patients undergoing cervical spine surgery, BS patients experienced lower rates of bowel issues, device-related, and overall complication than non-BS patients (P < 0.05). CONCLUSIONS: Bariatric surgery patients undergoing spine surgery experience lower overall complication rates than morbidly obese patients. This study warrants further investigation into these populations to mitigate risks associated with spine surgery for bariatric patients.

Despite worse baseline status depressed patients achieved outcomes similar to those in nondepressed patients after surgery for cervical deformity.

OBJECTIVE Depression and anxiety have been demonstrated to have negative impacts on outcomes after spine surgery. In patients with cervical deformity (CD), the psychological and physiological burdens of the disease may overlap without clear boundaries. While surgery has a proven record of bringing about significant pain relief and decreased disability, the impact of depression and anxiety on recovery from cervical deformity corrective surgery has not been previously reported on in the literature. The purpose of the present study was to determine the effect of depression and anxiety on patients' recovery from and improvement after CD surgery. METHODS The authors conducted a retrospective review of a prospective, multicenter CD database. Patients with a history of clinical depression, in addition to those with current self-reported anxiety or depression, were defined as depressed (D group). The D group was compared with nondepressed patients (ND group) with a similar baseline deformity determined by propensity score matching of the cervical sagittal vertical axis (cSVA). Baseline demographic, comorbidity, clinical, and radiographic data were compared among patients using t-tests. Improvement of symptoms was recorded at 3 months, 6 months, and 1 year postoperatively. All health-related quality of life (HRQOL) scores collected at these follow-up time points were compared using t-tests. RESULTS Sixty-six patients were matched for baseline radiographic parameters: 33 with a history of depression and/or current depression, and 33 without. Depressed patients had similar age, sex, race, and radiographic alignment: cSVA, T-1 slope minus C2-7 lordosis, SVA, and T-1 pelvic angle (p > 0.05). Compared with nondepressed individuals, depressed patients had a higher incidence of osteoporosis (21.2% vs 3.2%, p = 0.028), rheumatoid arthritis (18.2% vs 3.2%, p = 0.012), and connective tissue disorders (18.2% vs 3.2%, p = 0.012). At baseline, the D group had greater neck pain (7.9 of 10 vs 6.6 on a Numeric Rating Scale [NRS], p = 0.015), lower mean EQ-5D scores (68.9 vs 74.7, p < 0.001), but similar Neck Disability Index (NDI) scores (57.5 vs 49.9, p = 0.063) and myelopathy scores (13.4 vs 13.9, p = 0.546). Surgeries performed in either group were similar in terms of number of levels fused, osteotomies performed, and correction achieved (baseline to 3-month measurements) (p < 0.05). At 3 months, EQ-5D scores remained lower in the D group (74.0 vs 78.2, p = 0.044), and NDI scores were similar (48.5 vs 39.0, p = 0.053). However, neck pain improved in the D group (NRS score of 5.0 vs 4.3, p = 0.331), and modified Japanese Orthopaedic Association (mJOA) scores remained similar (14.2 vs 15.0, p = 0.211). At 6 months and 1 year, all HRQOL scores were similar between the 2 cohorts. One-year measurements were as follows: NDI 39.7 vs 40.7 (p = 0.878), NRS neck pain score of 4.1 vs 5.0 (p = 0.326), EQ-5D score of 77.1 vs 78.2 (p = 0.646), and mJOA score of 14.0 vs 14.2 (p = 0.835). Anxiety/depression levels reported on the EQ-5D scale were significantly higher in the depressed cohort at baseline, 3 months, and 6 months (all p < 0.05), but were similar between groups at 1 year postoperatively (1.72 vs 1.53, p = 0.416). CONCLUSIONS Clinical depression was observed in many of the study patients with CD. After matching for baseline deformity, depression symptomology resulted in worse baseline EQ-5D and pain scores. Despite these baseline differences, both cohorts achieved similar results in all HRQOL assessments 6 months and 1 year postoperatively, demonstrating no clinical impact of depression on recovery up until 1 year after CD surgery. Thus, a history of depression does not appear to have an impact on recovery from CD surgery.

van Neck-Odelberg Disease: A 3.5-Year Follow-Up Case Report and Systematic Review.

V an Neck-Odelberg disease (VND) is a benign skeletal overgrowth of the ischiopubic synchondrosis (IPS) in prepubescent patients. There is a paucity of long-term follow-up data and reviews on management decision-making. We report on a 15-year-old female, with a history of sickle-cell disease (HbSS), presenting with unilateral groin pain. Patient's physical examination, radiographs, and a literature-review determined a diagnosis of VND. Conservative treatment was issued. Clinical symptoms resolved at three months, followed by complete lesion resolution at three years. Additionally, a search of Medline (PubMed), EMBASE, and OVID databases was performed. Reports including VND/IPS diagnosis, treatment, or follow-up decisions were identified. Systematic-review found 17 relevant articles, reporting on 29 patients. Patients presented with groin (51.7%) or buttock (20.7%) pain, and were diagnosed using X-ray (n=23) and magnetic resonance imaging (MRI) (n=17). Twenty-five patients were treated conservatively, with two (8.0%) reports of surgical intervention. Average follow-up was 6.25 months. Our case report and systematic-review support conservative treatment for VND.

Metabolic Bone Disorders Are Predictors for 2-year Adverse Outcomes in Patients Undergoing 2-3 Level Anterior Cervical Discectomy and Fusion for Cervical Radiculopathy or Myelopathy.

STUDY DESIGN: Retrospective cohort study utilizing the New York statewide planning and research cooperative system. STUDY OBJECTIVE: To investigate postoperative complications of patients with metabolic bone disorders (MBDs) who undergo 2-3 levels of anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: MBDs and cervical degenerative pathologies, including cervical radiculopathy (CR) and cervical myelopathy (CM), are prevalent in the aging population. Complications with ACDF procedures can lead to increased hospitalization times, more expensive overhead, and worse patient outcomes. METHOD: Patients with CM/CR who underwent an ACDF of 2-3 vertebrae from 2009 to 2011 with a minimum 2-year follow-up were identified. Patients diagnosed with 1 or more MBD at baseline were compared with a control cohort without any MBD diagnosis. Cohorts were compared for demographics, hospital-related parameters, and 2-year medical, surgical, and overall complications. Binary multivariate logistic regression was used to identify independent predictors. RESULTS: A total of 22,276 patients were identified (MBD: 214; no-MBD: 22,062). Among MBD patients, the majority had vitamin D deficiency (n = 194, 90.7%). MBD patients were older (53.0 vs 49.7 y, P < 0.001), and with higher Deyo index (1.0 vs 0.5, P < 0.001). MBD patients had higher rates of medical complications, including anemia (6.1% vs 2.3%), pneumonia (4.7% vs 2.1%), hematoma (3.3% vs 0.7%), infection (2.8% vs 0.9%), and sepsis (3.7% vs 0.9%), as well as overall medical complications (23.8% vs 9.6%) (all, P ≤0.033). MBD patients also experienced higher surgical complications, including implant-related (5.7% vs 1.9%), wound infection (4.2% vs 1.2%), and wound disruption (0.9% vs 0.2%), and overall surgical complications (9.8% vs 3.2%) (all, P ≤0.039). Regression analysis revealed that a baseline diagnosis of MBD was independently associated with an increased risk of 2-year surgical complications (odds ratio = 2.10, P < 0.001) and medical complications (odds ratio = 1.84, P = 0.001). CONCLUSIONS: MBD as a comorbidity was associated with an increased risk of 2-year postoperative complications after 2-3 level ACDF for CR or CM.

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.

Is frailty responsive to surgical correction of adult spinal deformity? An investigation of sagittal re-alignment and frailty component drivers of postoperative frailty status.

PURPOSE: Frailty has been associated with adverse postoperative outcomes. Recently, a novel frailty index for preoperative risk stratification in patients with adult spinal deformity was developed. Components of the ASD-FI utilize patient comorbidity, clinical symptoms, and patient-reported-outcome-measures (PROMS). Our purpose was to investigate components of the Adult Spinal Deformity Frailty Index (ASD-FI) responsive to surgery and drivers of overall frailty. METHODS: Operative ASD patients ≥ 18 years, undergoing multilevel fusions, with complete baseline, 6 W, 1Y and 2Y ASD-FI scores. Descriptive analysis assessed demographics, radiographic parameters, and surgical details. Pearson bivariate correlations, independent and paired t tests assessed postoperative changes to ASD-FI components, total score, and radiographic parameters. Linear regression models determined the effect of successful surgery (achieving lowest level SRS-Schwab classification modifiers) on change in ASD-FI total scores. RESULTS: 409 6-week, 696 1-year, and 253 2-year operative ASD patients were included. 6-week and 1-year baseline frailty scores were 0.34, 2 years was 0.38. Following surgery, 6-week frailty was 0.36 (p = 0.033), 1 year was 0.25 (p < 0.001), and 2 years was 0.28 (p < 0.001). Of the ASD-FI variables, 17/40 improved at 6 weeks, 21/40 at 1 year, and 18/40 at 2 years. Successful surgery significantly predicted decreases in 1-year frailty scores (R = 0.27, p < 0.001), SRS-Schwab SVA modifier was the greatest predictor (Adjusted Beta: - 0.29, p < 0.001). CONCLUSIONS: Improvement in sagittal realignment and functional status correlated with improved postoperative frailty. Additional research and deformity sub-group analyses are needed to describe associations between specific functional activities that correlated with frailty improvement as well as evaluation of modifiable and non-modifiable indices.

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.

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.

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.

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.

Patients with psychiatric diagnoses have increased odds of morbidity and mortality in elective orthopedic surgery.

Psychiatric diagnoses (PD) present a significant burden on elective surgery patients and may have potentially dramatic impacts on outcomes. As ailments of the spine can be particularly debilitating, the effect of PD on outcomes was compared between elective spine surgery patients and other common elective orthopedic surgery procedures. This study included 412,777 elective orthopedic patients who were concurrently diagnosed with PD within the years 2005 to 2016. 30.2% of PD patients experienced a post-operative complication, compared to 25.1% for non-PD patients (p < 0.001). Mood Disorders (bipolar or depressive disorders) were the most commonly diagnosed PD for all elective Orthopedic procedures, followed by anxiety, then dementia (p < 0.001). Logistic regression analysis found PD to be a significant predictor of higher cost to charge ratio (CCR), length of stay (LOS), and death (all p < 0.001). Between, hand, elbow, and shoulder specialties, spine patients had the highest odds of increased CCR and unfavorable discharge, and the second highest odds of death (all p < 0.001).

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.

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.

Bariatric Surgery Population at Significantly Increased Risk of Spinal Disorders and Surgical Intervention Compared With Morbidly Obese Patients.

INTRODUCTION: Obesity is associated with acceleration of musculoskeletal degenerative diseases and functional impairment secondary to spinal disorders. Bariatric surgery (BS) is an increasingly common treatment for severe obesity but can affect bone and mineral metabolism. The effect of BS on degenerative spinal disorders is yet to be fully described. The aim of our study was to analyze changes in bariatric patients' risk for spinal degenerative diseases and spinal surgery. METHODS: Retrospective analysis of the prospectively collected New York State Inpatient Database (NYSID) years (2004-2013) using patient linkage codes. The incidence of degenerative spinal diagnoses and spinal surgery was queried using International Classification of Diseases, Ninth Revision (ICD)-9 codes for morbidly obese patients (ICD-9 278.01) with and without a history of BS. The incidence of degenerative spinal diagnoses and spinal surgery was determined using χ tests for independence. Logistic testing controlled for age, sex, and comorbidity burden. RESULTS: A total of 18,176 patients were identified in the NYSID database with a history of BS and 146,252 patients were identified as morbidly obese without a history of BS. BS patients have a significantly higher rate of spinal diagnoses than morbidly obese patients without BS (19.3% vs. 8.1%, P<0.001). Bariatric patients were more likely to have spinal diagnoses and procedures than nonbariatric obese patients (P<0.001). This was mostly observed in lumbar spinal stenosis (5.0%), cervical disk herniation (3.3%), lumbar disk degeneration (3.4%), lumbar spondylolisthesis (2.9%), lumbar spondylosis (1.9%), and cervical spondylosis with myelopathy (2.0%). Spine procedure rates are higher for bariatric patients than nonbariatric overall (25.6% vs. 2.3, P<0.001) and for fusions and decompressions (P<0.001). When controlling for age, sex, and comorbidities (and diagnosis rate with regards to procedure rates), these results persist, with BS patients having a higher likelihood of spinal diagnoses and procedures. In addition, bariatric patients had a lower comorbidity burden than morbidly obese patients without a history of BS. CONCLUSIONS: Morbidly obese BS patients have a dramatically higher incidence of spinal diagnoses and procedures, relative to morbidly obese patients without BS. Further study is necessary to determine if there is a pathophysiological mechanism underlying this higher risk of spinal disease and intervention in bariatric patients, and the effect of BS on these rates following treatment. LEVEL OF EVIDENCE: Level III.

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

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