Faculty Bibliography

Introduction/UNASSIGNED:This study assessed the incidence and risk factors for pseudarthrosis among primary spine fusion patients. Methods/UNASSIGNED:-tests. Binary logistic regression assessed patient-related and procedure-related predictors for pseudarthrosis. Results/UNASSIGNED:=0.026). Conclusions/UNASSIGNED:Alcoholism and surgical revision are major risk factors for pseudarthrosis in patients undergoing spine fusion.

Background/UNASSIGNED:The study aimed to characterize trends in incidence, etiology, fracture types, surgical procedures, complications, and concurrent injuries associated with traumatic pediatric cervical fracture using a nationwide database. Methods/UNASSIGNED:< .05. Results/UNASSIGNED:< .001). Conclusions/UNASSIGNED:Since 2003, incidence, complications, concurrent injuries, and fusions have increased. CCI, SCI, falls, and sports injuries were significant predictors of surgical intervention. Decreased mortality and SCI rates may indicate improving emergency medical services and management guidelines. Level of Evidence/UNASSIGNED:III. Clinical Relevance/UNASSIGNED:Clinicians should be aware of increased case complexity in the onset of added perioperative complications and concurrent injuries. Cervical fractures resultant of sports injuries should be scrutinized for concurrent SCIs.

STUDY DESIGN:Retrospective review of KID Inpatient Database (KID) from 2003, 2006, 2009, and 2012. OBJECTIVES:The aim of this study was to evaluate the impact of advances in spinal surgery on patient outcomes in the treatment of Scheuermann kyphosis (SK). SUMMARY OF BACKGROUND DATA:SK is one of the most common causes of back pain in adolescents. Trends in diagnoses and surgical treatment and approach to SK have not been well described. METHODS:SK patients aged 0-20 years in KID were identified by ICD-9 code 732.0. KID-supplied year- and hospital-trend weights were used to establish prevalence. Patient demographics, surgical details, and outcomes were analyzed with analysis of variance. RESULTS:A total of 1,070 SK patients were identified (33.2% female), with increasing incidence of SK diagnosed from 2003 to 2012 (3.6-7.5 per 100,000, p < .001). The average age of operative patients was 16.1±2.0 years and did not change (16.27-16.06 years, p = .905). The surgical rate has not changed over time (72.8%-72.8%, p = .909). Overall, 96.3% of operative patients underwent fusion, with 82.2% of cases spanning ≥4 levels; in addition, 8.6% underwent an anterior-only surgery, 74.6% posterior-only, and 13.6% combined approach. From 2003 to 2012, rates of posterior-only surgeries increased (62.4%-84.4%, p < .001) whereas the rate of combined-approach surgeries decreased (37.6%-8.8%, p < .001). Overall complication rates for SK surgeries have decreased (2003: 20.9%; 2012: 11.9%, p = .029). Concurrently, the rate of ≥4-level fusions has increased (43.5%-89.6%, p < .001), as well as the use of Smith-Peterson (7.8%-23.6%, p < .001) and three-column osteotomies (0.0%-2.7%, p = .011). In subanalysis comparing posterior to combined approaches, complication rates were significantly different (posterior: 9.88%, combined: 19.46%, p = .005). Patients undergoing a combined approach have a longer length of stay (LOS) than patients undergoing a posterior-only approach (7.8 vs. 5.6 days, p < .001). CONCLUSIONS:Despite unchanged demographics and operative rates in SK, there has been a shift from combined to isolated posterior approaches, with a concurrent increase in levels treated. A combined approach was associated with increased complication rates, LOS, and total charges compared to isolated approaches. Awareness of these inherent differences is important for surgical decision making and patient education. LEVELS OF EVIDENCE:Level III.

Background: For surgical adult spinal deformity (ASD) patients, incorporating restoration of appropriate Roussouly Classificaion shape into surgical planning may improve outcomes. With the introduction and use of the SRS-Schwab ASD classification system, it's important to compare the utility of both classification frameworks as they relate to surgical outcomes.
Purpose(s): Compare outcomes of surgical ASD patients classified by both Roussouly and Schwab systems.
Method(s): Retrospective review of prospective ASD database. ASD patients were grouped by theoretical Roussouly type (1: PI<45-, LL apex below L4; 2: PI<45-, LL apex above L4-L5 space; 3: 45-Result(s): Included: 515 ASD patients (59 +/- 14yrs, 80%F). Preop breakdown of current Roussouly types: Type 1 (10%), Type 2 (54%), Type 3 (24%), Type 4 (12%). Preop mismatch between current and theoretical types was 60%. By 2Y, 16% of patients matched Roussouly types. Matched and Mismatched groups did not differ in rates of reaching MCID for any HRQL metrics by 2Y (all p[0.1). Reop, PJK, and complications did not differ between Matched and Mismatched (all p[0.1), though Mismatched patients showed a trend of increased instrumentation failure (17% vs 26%, p = 0.080). By 2Y, 28% of patients improved in PT Schwab modifier, 37% in SVA, and 46% in PI-LL. Patients that improved in PT modifier reached MCID at higher rates for ODI and SRS Activity by 2Y, and had lower rates of instrumentation failure than those that did not (Table 1). Patients that both Matched Roussouly at 2Y and improved in all Schwab modifiers met MCID for ODI and SRS Activity at higher rates than patients that did not. Roussouly Match patients that improved in Schwab PT met SRS Activity MCID at a higher rate, and had less renal, infection, and neurologic complications than patients that did not. Roussouly Match patients that improved in Schwab SVA also had superior SF-36 scores and fewer cardiopulmonary complications (all p<0.05).
Conclusion(s): For surgical ASD patients, isolated restoration of sagittal spinal shape per the Roussouly system was not associated with superior clinical outcomes or complications by 2Y. In contrast, improvement in PT, per SRS-Schwab system, was associated with improvement in low-back disability by 2Y. Collectively, patients that matched Roussouly type and improved in Schwab modifiers had superior complication and patient-reported outcomes by 2Y. These results indicate concurrent consideration of both classification systems may offer utility in establishing optimal realignment targets

BACKGROUND:Surgical treatments for adult cervical spinal deformity (ACSD) are often complex and have high complication rates. OBJECTIVE:To assess all-cause mortality following ACSD surgery. METHODS:ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Clinical and surgical parameters and all-cause mortality were assessed. RESULTS:Of 123 ACSD patients, 120 (98%) had complete baseline data (mean age, 60.6 yr). The mean number of comorbidities per patient was 1.80, and 80% had at least 1 comorbidity. Surgical approaches included anterior only (15.8%), posterior only (50.0%), and combined anterior/posterior (34.2%). The mean number of vertebral levels fused was 8.0 (standard deviation [SD] = 4.5), and 23.3% had a 3-column osteotomy. Death was reported for 11 (9.2%) patients at a mean of 1.1 yr (SD = 0.76 yr; range = 7 d to 2 yr). Mean follow-up for living patients was 1.2 yr (SD = 0.64 yr). Causes of death included myocardial infarction (n = 2), pneumonia/cardiopulmonary failure (n = 2), sepsis (n = 1), obstructive sleep apnea/narcotics (n = 1), subsequently diagnosed amyotrophic lateral sclerosis (n = 1), burn injury related to home supplemental oxygen (n = 1), and unknown (n = 3). Deceased patients did not significantly differ from alive patients based on demographic, clinical, or surgical parameters assessed, except for a higher major complication rate (excluding mortality; 63.6% vs 22.0%, P = .006). CONCLUSION/CONCLUSIONS:All-cause mortality at a mean of 1.2 yr following surgery for ACSD was 9.2% in this prospective multicenter series. Causes of death were reflective of the overall high level of comorbidities. These findings may prove useful for treatment decision making and patient counseling in the context of the substantial impact of ACSD.

BACKGROUND CONTEXT/BACKGROUND:Distal Junctional Kyphosis (DJK) is a primary concern of surgeons correcting cervical deformity. Identifying patients and procedures at higher risk for developing this condition is paramount in improving patient selection and care. PURPOSE/OBJECTIVE:Develop a risk index for DJK development in the first year after surgery. STUDY DESIGN/SETTING/METHODS:Retrospective review of a prospective multicenter cervical deformity database. PATIENT SAMPLE/METHODS:). OUTCOME MEASURES/METHODS:Development of DJK at any time before 1 year. METHODS:distal vertebra, as well as a change in this angle by <-10 from baseline. Conditional Inference Decision Trees were used to identify factors predictive of DJK incidence and the cut-off points at which they have an effect. A conditional Variable-Importance table was constructed based on a non-replacement sampling set of 2000 Conditional Inference Trees. 12 influencing factors were found, binary logistic regression for each variable at significant cut-offs indicated their effect size. RESULTS:(OR:5.4 CI:2.20-13.23), and [6] C4_Tilt >56.7 (OR:5.0 CI:1.90-13.1).Clinically, combined approaches (OR:2.67 CI:1.21-5.89) and usage of Smith Petersen osteotomy (OR:2.55 CI:1.02-6.34) were the most important predictors for DJK. CONCLUSIONS:In a surgical cohort of cervical deformity patients, we found a 23.8% incidence of DJK. Different procedures and patient malalignment predicted incidence of DJK up to 1-year. Preoperative TS-CL, Cervical Kyphosis, SVA, and Cervical Lordosis all strongly predicted DJK at specific cut-off points. Knowledge of these factors will potentially help direct future study and strategy aimed at minimizing this potentially dramatic occurrence.

BACKGROUND:Cervical spine (C-spine) injuries cause significant morbidity and mortality among the elderly. Although the population of older-adults ≥65 years in the US is expanding, estimates of the burden and outcome of C-spine injury are lacking. METHODS:The Nationwide Inpatient Sample 2001-2010 was analyzed. International Classification of Diseases codes identified patients with isolated C-spine fractures (ICF) and C-spine fractures with spinal cord injury (CSCI). Annual admission and mortality rates were calculated using US-Census data. RESULTS:A total of 167,278 older-adults were included. Median age was 81 years (IQR=74-86). Most patients were female (54.9%), had Medicare coverage (77.6%), treated in teaching hospitals (63.2%), and falls were the leading injury-mechanism (51.2%). ICF occurred in 91.3%, while CSCI occurred in 8.7% (p<0.001). ICF was more common in ≥85 year-olds and CSCI in 65-69 year-olds (p<0.001). The most common injured C-spine level in ICF was C2-level (47.6%, p<0.001), and in CSCI was C1-C4 level (4.5%, p<0.001). Overall, 15.8% underwent C-spine surgery. Hospitalization rates increased from 26/100,000 in 2001 to 68/100,000 in 2010 (∼167% change, p<0.001). Correspondingly, overall mortality increased from 3/100,000 in 2001 to 6/100,000 in 2010, p<0.001. In-hospital mortality was 11.3%, was strongly associated with increasing age and CSCI (p<0.001). CONCLUSIONS:In summary, C-spine fractures among US older-adults constitute a significant healthcare burden. ICF occur commonly, C2-vertebra fractures are most frequent, while CSCI are linked to increased hospital-resource utilization and worse outcomes. The incidence of C-spine fractures and mortality more than doubled over the past decade; however, proportional in-hospital mortality is decreasing.

Chiari malformations are structural defects in the posterior fossa where the cerebellum displaces caudally into the foramen magnum and upper spinal canal. These malformations are classified by severity as Types 1-4, each presenting with different associated and/or concurrent conditions and anomalies. The aim of this study was to utilize a nationwide database to study patients with Chiari malformations including their concurrent diagnoses and associated anomalies. Using a retrospective review of the Nationwide Inpatient Sample (NIS) database from 2003 to 2012, Chiari malformations were assessed by Chiari type and rates of concurrence for various additional anomalies were evaluated using cross-tabulations. There were 305,726 national cases of Chiari Type 1, 119,632 cases of Chiari Type 2, 15,540 cases of Type 3, and 79,663 cases of Type 4. Overall 44.3% of Chiari patients have at least one concurrent anomaly. Stratified by Chiari Type, 7.1% of Type 1 patients, 12.3% of Type 2, and 100% of Type 3 and 4 have at least one concurrent anomaly. The most common isolated neurologic associations were tethered cord, syringomyelia, and hydrocephalus, while the most common anomaly clusters were syringomyelia and scoliosis in Type 1 (0.63), tethered cord syndrome and scoliosis (0.72%) in Type 2, encephalocele and acquired hydrocephalus (11.45%) in Type 3, and reduction deformity of the brain with acquired hydrocephalus (15.95%) in Type 4. Chiari malformations have strong associations with other abnormalities outside of known relationships in the current classification. While neurologic abnormalities are most common, additional body systems are frequently involved especially with worsening hindbrain defects.

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.

STUDY DESIGN/METHODS:Retrospective analysis of 2 prospectively collected multicenter databases, one for cervical deformity (CD) and the other for general adult spinal deformity. OBJECTIVE:To investigate the relative quality-of-life and disability burden in patients with uncompensated cervical, thoracolumbar, or cervical and thoracolumbar deformities. SUMMARY OF BACKGROUND DATA/BACKGROUND:The relative quality-of-life burden of cervical and thoracolumbar deformities have never been compared with each other. This may have significant implications when deciding on the appropriate treatment intervention for patients with combined thoracolumbar and cervical deformities. METHODS:When defining CD C2-C7 sagittal vertical axis (SVA)>4 cm was used while a C7-S1 SVA>5 cm was used to defined thoracolumbar deformity. Patients with both SVA criteria were defined as "combined." Primary analysis compared patients in the different groups by demographic, comorbidity data, and quality-of-life scores [EuroQOL 5 dimensions questionnaire (EQ-5D)] using t tests. Secondary analysis matched deformity groups with propensity scores matching based on baseline EQ-5D scores. Differences in disease-specific metrics [the Oswestry Disability Index, Neck Disability Index, modified Japanese Orthopaedic Association questionnaire (mJOA)] were analyzed using analysis of variance tests and post hoc analysis. RESULTS:In total, 212 patients were included in our analysis. Patients with CD only had less neurological deficits (mJOA: 14.6) and better EQ-5D (0.746) scores compared with patients with combined deformities (11.9, 0.716), all P<0.05. Regarding propensity score-matched deformity cohorts, 99 patients were matched with similar quality-of-life burden, 33 per deformity cohort. CD only patients had fewer comorbidities (1.03 vs. 2.12 vs. 2.70; P<0.001), whereas patients with combined deformity had more baseline neurological impairment compared with CD only patients (mJOA: 12.00 vs. 14.25; P=0.050). CONCLUSIONS:Combined deformity patients were associated with the lowest quality-of-life and highest disability. Furthermore, regarding deformity cohorts matched by similar baseline quality-of-life status (EQ-5D), patients with combined deformities were associated with significantly worse neurological impairments. This finding implies that quality of life may not be a direct reflection of a patient's disability status, especially in patients with combined cervical and thoracolumbar deformities. LEVEL OF EVIDENCE/METHODS:Level III.