Faculty Bibliography

STUDY DESIGN/METHODS:Retrospective review OBJECTIVE.: Develop a simplified frailty index for CD patients SUMMARY OF BACKGROUND DATA.: To improve preoperative risk stratification for surgical cervical deformity (CD) patients, a CD frailty index (CD-FI) incorporating 40 health deficits was developed. While novel, the CD-FI is clinically impractical due to the large number of factors needed for its calculation. To increase clinical utility, a simpler, modified CD-FI (mCD-FI) is necessary. METHODS:CD patients (C2-C7 Cobb>10°, CL>10°, cSVA>4 cm, or CBVA>25°) >18yr with preoperative CD-FI component factors. Pearson bivariate correlation assessed relationships between component deficits of the CD-FI and overall CD-FI score. Top deficits contributing to CD-FI score were included in multiple stepwise regression models. Deficits from model with largest R were dichotomized, and the mean score of all deficits calculated, resulting in mCD-FI score from 0 to 1. Patients were stratified by mCD-FI: Not Frail (NF, <0.3), Frail (0.3-0.5), Severely Frail (SF, >0.5). Means comparison tests established correlations between frailty category and clinical outcomes. RESULTS:Included: 121 CD patients (61 ± 11yr, 60%F). Multiple stepwise regression models identified 15 deficits as responsible for 86% of the variation in CD-FI; these factors were used to construct the mCD-FI. Overall, mean mCD-FI was 0.31 ± 0.14. Breakdown of patients by mCD-FI category: NF: 47.9%, Frail: 46.3%, SF: 5.8%. Compared to NF and Frail, SF patients had the longest inpatient hospital stays (P = 0.042), as well as greater baseline neck pain (P = 0.033), inferior NDI scores (P<0.001) and inferior EQ-5D scores (P < 0.001). Frail patients had higher odds of superficial infection (OR:1.1[1.0-1.2]), and SF patients had increased odds of mortality (OR:8.3[1.3-53.9]). CONCLUSIONS:Increased frailty, assessed by mCD-FI, correlated with increased length of stay, neck pain, and decreased health-related quality of life. Frail patients were at greater risk for infection, and severely frail patients had greater odds of mortality. This relationship between frailty and clinical outcomes suggests that mCD-FI offers clinical utility as a preoperative risk stratification tool. LEVEL OF EVIDENCE/METHODS:3.

OBJECTIVE:We sought to compare timing of intervention for patients with spinal cord injury (SCI) requiring surgical procedures during weekend versus weekday admissions. METHODS:The National Inpatient Sample database from 2012 to 2014 was queried to identify patients with SCI who underwent surgical treatment (decompression with or without stabilization) as an emergent/urgent procedure. Timing of intervention, inpatient morbidity, and inpatient mortality were compared between patients admitted during the weekend versus a weekday. Multiple logistic regression analyses were also performed. RESULTS:A total of 9390 patients were identified (mean age 55 years, 73.2% male) from the database, with 34.1% admitted during the weekend and 65.9% during a weekday. The average day of intervention for the entire cohort was 2.8 (SD 3.9, interquartile range 1-4); day 2.7 (standard deviation [SD] 4.0) versus day 2.8 ([SD] 3.9) for patients admitted in a weekend versus weekday (P = 0.418). After controlling for patient age, sex, and injury severity score on multiple logistic regression analysis, weekend admission was not significantly associated with early intervention (odds ratio [OR] 0.99; 95% confidence interval [CI], 0.82-1.21; P = 0.993), complication occurrence (OR 1.09; 95% CI, 0.86-1.38; P = 0.476), or inpatient mortality (OR 0.83; 95% CI, 0.44-1.56; P = 0.563). Patients with complete/American Spinal Injury Association A injuries were more likely to undergo early intervention (OR 2.09; 95% CI, 1.31-3.31; P = 0.002). CONCLUSION/CONCLUSIONS:In this national study, patients with SCI who were admitted during the weekend received surgical intervention as early as patients admitted during a weekday. Furthermore, no differences in complication or mortality rates between groups were found.

Patient-specific rods designed based on a particular pre-operative plan are a recent advancement to help achieve desired operative alignment goals. This study investigated the role of pre-operative planning and patient-specific rods on post-operative alignment and outcomes. Patients were grouped according to use of pre-operative planning and patient-specific, pre-contoured rods (PLAN) or absence of planning/rods (NON). Pre-operative and post-operative alignment were measured: cervical sagittal vertical axis (cSVA), cervical lordosis (CL), T1 Slope minus CL (TS-CL). Alignment differences between the groups were assessed using independent and paired samples t-tests. 34 patients were identified (15 PLAN, 19 NON). Pre- and post-operative CL, cSVA and TS were similar between the two groups (p > 0.05), though pre-operative TS-CL was slightly higher in PLAN patients (28.13° versus 18.42°, p = 0.049). There were no improvement differences pre- to post-operative for CL, cSVA and TS between the groups (p > 0.05). However, PLAN patients exhibited a greater correction of TS-CL, with an average of 5.8° decrease versus a 3.5° increase in TS-CL for NON patients (p = 0.015). PLAN patients did not demonstrate a significant change from pre- to post-operative alignment for cSVA or TS-CL (cSVA: 27.5 mm to 31.1 mm, p = 0.255; TS-CL: 28.1° to 22.3°, p = 0.13), though their TS-CL did trend towards significant post-operative improvement. In contrast, NON patients worsened in cSVA and TS-CL post-operatively (cSVA: 21.8 mm to 30.3 mm, p < 0.001; TS-CL: 18.4° to 22.0°, p = 0.035). Multi-segment posterior decompression and fusion patients have the potential to worsen with regards to post-operative alignment without pre-operative planning. Patients with pre-contoured rods and pre-operative planning exhibited a greater correction of TS-CL after surgery than un-planned cases, though limited by the pre-operative difference in cervical-thoracic mismatch between planned and unplanned cases.

We developed a predictive model to describe risk factors for complications in cervical deformity surgeries. Cervical deformity (CD) surgical patients are growing in number, but remain under-studied in the literature. CD was defined as at least one of the following: C2-C7 Cobb >10°, CL >10°, cSVA >4 cm, CBVA >25°. Patient demographics and clinical data were assessed as risk factors for medical/surgical complications using multivariate regression models. 123 patients underwent CD surgery (60.6 yrs, 60.8% F). The most common complications were neurologic (24.4%), dysphagia (13.0%), cardiopulmonary (11.4%), infection (9.7%). 51 (41.5%) of patients experienced a medical complication and 73 (59.3%) had a surgical complication. An overall complication was predicted with high accuracy (AUC = 0.79) by the following combinations of factors: higher baseline EQ5D pain and lower baseline EQ5D anxiety/depression scores, and higher cervical and global SVA. A medical complication can be predicted by male gender, baseline mJOA score, and cervical SVA (AUC = 0.770). A surgical complication can be predicted by higher estimated blood loss, lower anxiety scores, and larger global SVA (AUC = 0.739). 64.2% of patients undergoing cervical deformity correction sustained any complication. While the most reliable predictor of the occurrence of a complication involved a cluster of risk factors, a radiographic baseline sagittal parameter of cervical SVA was the strongest isolated predictor for complications across categories. Although these findings are specific to a cervical population with moderate to severe deformities, collectively they can be utilized for pre-operative risk assessment and patient education.

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:The impact of obesity on global spinopelvic alignment is poorly understood. This study investigated the effect of body mass index on achieving alignment targets and compensation mechanisms after corrective surgery for adult spinal deformity (ASD). METHODS:Retrospective review of a single-center database. Inclusion: patients ≥18 years with full-body stereographic images (baseline and 1 year) and who met ASD criteria (sagittal vertical axis [SVA] >5 cm, pelvic incidence minus lumbar lordosis [PI-LL] >10°, coronal curvature >20° or pelvic tilt >20°). Patients were stratified by age (<40, 40-65, and ≥65 years) and body mass index (<25, 25-30, and >30). Postoperative alignment was compared with age-adjusted ideal values. Prevalence of patients who matched ideals and unmatched (undercorrected/overcorrected) was assessed. Health-related quality of life (HRQL) scores, alignment, and compensatory mechanisms were compared across cohorts using analysis of variance and temporally with paired t tests. RESULTS:A total of 116 patients were included (average age, 62 years; 66% female). After corrective surgery, obese and overweight patients had more residual malalignment (worse PI-LL, T1 pelvic angle, pelvic tilt, and SVA) compared with normal patients (P < 0.05). In addition, obese and overweight patients recruited more pelvic shift (obese, 62.36; overweight, 49.80; normal, 31.50) and had a higher global sagittal angle (obese, 6.51; overweight, 6.35; normal, 3.40) (P < 0.05). Obese and overweight patients showed lower overcorrection rates and higher undercorrection rates (P < 0.05). Obese patients showed worse postoperative HRQL scores (Scoliosis Research Society 22 Questionnaire, Oswestry Disability Index, visual analog scale-leg) than did overweight and normal patients (P < 0.05). Obese and overweight patients who matched age-adjusted alignment targets for SVA or PI-LL showed no HRQL improvements (P > 0.05). CONCLUSIONS:After surgery, obese patients were undercorrected, showed more residual malalignment, recruited more pelvic shift, and had a greater global sagittal angle and worse HRQL scores. The benefits from age-adjusted alignment targets seem to be less substantial for obese and overweight patients.