Faculty Bibliography

STUDY DESIGN/UNASSIGNED:Retrospective cohort study. OBJECTIVE/UNASSIGNED:To assess the impact of race on complications following spinal tumor surgery. METHODS/UNASSIGNED:Adults with cancer who underwent spine tumor surgery were identified in the American College of Surgeons National Surgical Quality Improvement Program datasets from 2012 to 2016. Clavien-Dindo Grade I-II (minor complications) and Clavien-Dindo Grade III-V (major complications including 30-day mortality) complications were compared between non-Hispanic Whites (NHW) and Black patients. A multivariable analysis was also conducted. RESULTS/UNASSIGNED:= .011). CONCLUSION/UNASSIGNED:Black patients who underwent metastatic spinal tumor surgery were at a significantly increased risk of perioperative morbidity compared to NHW patients independent of baseline and operative characteristics. Major complications did not differ between groups. Race should be further studied in the context of metastatic spine disease to improve our understanding of these disparities.

Introduction/UNASSIGNED:Patients with symptomatic cervical deformity (CD) requiring surgical correction often present with hyperkyphosis (HK), though patients with hyperlordotic curves may require surgery as well. Few studies have investigated differences in CD-corrective surgery with regards to HK and hyperlordosis (HL). Materials and Methods/UNASSIGNED:Operative CD patients (C2-C7 Cobb >10°, cervical lordosis [CL] >10°, cervical sagittal vertical axis [cSVA] >4 cm, chin-brow vertical angle >25°) with baseline (BL) and 1Y radiographic data. Patients were stratified based on BL C2-7 lordosis (CL) angle: those >1 standard deviation (SD) from the mean (-6.96° ±21.47°) were hyperlordotic (>14.51°) or hyperkyphotic (≤28.43°) depending on directionality. Patients within 1 SD were considered the control group. Results/UNASSIGNED:< 0.001), however postoperative differences in McGregor's slope and C0-C2 were not significant. HK drivers of deformity were primarily C (90%), whereas HL had primary computed tomography (38.1%), upper thoracic (23.8%), and C (14.3%) drivers. Conclusions/UNASSIGNED:Hyperlodotic patients trended higher revision rates with greater radiographic malalignment at 1Y postoperative, perhaps due to undercorrection compared to kyphotic etiologies.

Background/UNASSIGNED:To optimize quality of life in patients with cervical deformity (CD), there may be alignment targets to be prioritized. Objective/UNASSIGNED:To prioritize the cervical parameter targets for alignment. Methods/UNASSIGNED:°) were excluded. Patients assessed: Meeting Minimal Clinically Important Difference (MCID) for NDI (<-15 ΔNDI). Ratios of correction were found for regional parameters categorized by Primary Ames Driver (C or CT). Decision tree analysis assessed cut-offs for differences associated with meeting NDI MCID at 1Y. Results/UNASSIGNED:TS-CL. Conclusions/UNASSIGNED:Certain ratios of correction of cervical parameters contribute to improving neck disability. Prioritizing these radiographic alignment parameters may help optimize patient-reported outcomes for patients undergoing CD surgery.

Introduction/UNASSIGNED: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/UNASSIGNED:-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/UNASSIGNED:> 0.05). Conclusions/UNASSIGNED: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.

Background/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED: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/UNASSIGNED: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.

Background/UNASSIGNED:The lower instrumented vertebrae (LIVs) in cervical deformity (CD) constructs may have varying effects on patient outcomes that are still poorly understood. Objective/UNASSIGNED:The objective of the study is to compare outcomes in CD patients undergoing instrumented correction according to the relation of LIV with primary driver (PD). Methods/UNASSIGNED:Patients who met radiographic criteria for CD were included in the study. Patients were stratified by PD of deformity: cervical (C) through AMES classification (TS-CL >20 or cervical sagittal vertical axis >40) and thoracic (T) through hyper/hypokyphosis (TK) from T4-T12 (60 < TK < 40). Patients were further stratified by LIV in relation to curve apex (above/below). Univariate and multivariate analyses identified group differences in postoperative health-related quality-of-life and distal junctional kyphosis (DJK) (>10° LIV and LIV + 2) rate up to 1 year. Results/UNASSIGNED:= 0.119). Conclusions/UNASSIGNED:Stopping before apex was more common in patients with a primary thoracic driver (T) and associated with deleterious effects. Primary cervical driver (C) tended to have LIVs inclusive of CL apex with lower rates of DJK.

STUDY DESIGN/UNASSIGNED:Comparative cohort study. OBJECTIVE/UNASSIGNED:Factors that influence the lower instrumented vertebra (LIV) selection in adult cervical deformity (ACD) are less reported, and outcomes in the cervicothoracic junction (CTJ) and proximal thoracic (PT) spine are unclear. METHODS/UNASSIGNED:A prospective ACD database was analyzed using the following inclusion criteria: LIV between C7 and T5, upper instrumented vertebra at C2, and at least a 1-year follow-up. Patients were divided into CTJ (LIV C7-T2) and PT groups (LIV T3-T5) based on LIV levels. Demographics, operative details, radiographic parameters, and the health-related quality of life (HRQOL) scores were compared. RESULTS/UNASSIGNED:= 0.001). Complications and reoperations were comparable. The HRQOL scores were not different preoperatively and at 1-year follow-up. CONCLUSIONS/UNASSIGNED:The selection of PT LIV in cervical deformities was more common in patients with larger baseline deformities, who were more likely to undergo pedicle-subtraction osteotomy. Despite this, the complications and HRQOL outcomes were comparable at 1-year follow-up.

BACKGROUND:Frailty severity may be an important determinant for impaired recovery after cervical spine deformity (CD) corrective surgery. OBJECTIVE:To evaluate postop clinical recovery among CD patients between frailty states undergoing primary procedures. METHODS:Patients >18 yr old undergoing surgery for CD with health-related quality of life (HRQL) data at baseline, 3-mo, and 1-yr postoperative were identified. Patients were stratified by the modified CD frailty index scale from 0 to 1 (no frailty [NF] <0.3, mild/severe fraily [F] >0.3). Patients in NF and F groups were propensity score matched for TS-CL (T1 slope [TS] minus angle between the C2 inferior end plate and the C7 inferior end plate [CL]) to control for baseline deformity. Area under the curve was calculated for follow-up time intervals determining overall normalized, time-adjusted HRQL outcomes; Integrated Health State (IHS) was compared between NF and F groups. RESULTS:A total of 106 CD patients were included (61.7 yr, 66% F, 27.7 kg/m2)-by frailty group: 52.8% NF, 47.2% F. After propensity score matching for TS-CL (mean: 38.1°), 38 patients remained in each of the NF and F groups. IHS-adjusted HRQL outcomes from baseline to 1 yr showed a significant difference in Euro-Qol 5 Dimension scores (NF: 1.02, F: 1.07, P = .016). No significant differences were found in the IHS Neck Disability Index (NDI) and modified Japanese Orthopedic Association between frailty groups (P > .05). F patients had more postop major complications (31.3%) compared to the NF (8.9%), P = .004, though DJK occurrence and reoperation between the groups was not significant. CONCLUSION/CONCLUSIONS:While all groups exhibited improved postop disability and pain scores, frail patients experienced greater amount of improvement in overall health state compared to baseline disability. This signifies that with frailty severity, patients have more room for improvement postop compared to baseline quality of life.

STUDY DESIGN/METHODS:Retrospective review of a prospective multicenter cervical deformity database OBJECTIVE.: To examine the differences in sagittal alignment correction between three positioning methods in cervical spinal deformity surgery (CD). SUMMARY OF BACKGROUND DATA/BACKGROUND:Surgical correction for CD is technically demanding and various techniques are utilized to achieve sagittal alignment objectives. The effect of different patient positioning techniques on sagittal alignment correction following CD remains unknown. METHODS:Patients with sagittal deformity who underwent a posterior approach (with and without anterior approach) with an upper instrumented vertebra of C6 or above. Patients with Grade 5, 6 or 7 osteotomies were excluded. Positioning groups were Mayfield skull clamp, bivector traction, and halo ring. Pre-operative lower surgical sagittal curve (C2-C7), C2-C7 sagittal vertical axis (cSVA), cervical scoliosis, T1 slope minus cervical lordosis (TS-CL), T1 Slope (T1S), chin-brow vertebral angle (CBVA), C2-T3 curve, and C2-T3 SVA was assessed and compared to post-operative radiographs. Segmental changes were analyzed using the Fergusson method. RESULTS:80 patients (58% female) with a mean age was 60.6 ± 10.5 years (range 31-83) were included. The mean post-operative C2-C7 lordosis was 7.8°±14 and C2-C7 SVA was 34.1mm ± 15. There were overall significant changes in cervical alignment across the entire cohort, with improvements in T1 slope (p < 0.001), C2-C7 (p < 0.001), TS-CL (p < 0.001), and cSVA (p = 0.006). There was no difference post-operatively of any radiographic parameter between positioning groups (p > 0.05). The majority of segmental lordotic correction was achieved at C4-5-6 (Mean 6.9°±11). Additionally, patients who had bivector traction applied had had significantly more segmental correction at C7-T1-T2 compared to Mayfield and halo traction (4.2° vs. 0.3° vs. -1.7° respectively, p < 0.027). CONCLUSION/CONCLUSIONS:Post-operative cervical sagittal correction or alignment was not affected by patient position. The majority of segmental correction occurred at C4-5-6 across all positioning methods, while bivector traction had the largest corrective ability at the cervicothoracic junction. LEVEL OF EVIDENCE/METHODS:4.

STUDY DESIGN/METHODS:Retrospective review of a prospective database. OBJECTIVE:Identify demographic, surgical, and radiographic factors that predict superior recovery kinetics following CD corrective surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:Analyses of cervical deformity (CD) corrective surgery use area-under-the-curve (AUC) to assess health-related quality of life (HRQL) metrics throughout recovery. METHODS:Outcome Measures: Baseline (BL) to 1-Year (1Y) HRQL (Neck Disability Index [NDI]). CD criteria: C2-7 Cobb angle>10°, coronal Cobb angle>10°, cSVA>4 cm TS-CL>10°, or CBVA>25°. AUC normalization divided BL and postoperative outcomes by BL. Normalized scores(y-axis) were plotted against follow-up(x-axis). AUC was calculated and divided by cumulative follow-up length to determine overall, time-adjusted recovery (Integrated Health State [IHS]). IHS NDI was stratified by quartile, uppermost 25% being 'Superior' Recovery Kinetics (SRK) vs. 'Normal' Recovery Kinetics (NRK). BL demographic, clinical, and surgical information predicted SRK using generalized linear modeling. RESULTS:98 patients included (62 ± 10yrs, 28 ± 6 kg/m2, 65%F, CCI:0.95), 6% smokers, 31% smoking history. Surgical approach: combined (33%), posterior (49%), anterior (18%). Posterior levels fused: 8.7, anterior: 3.6, EBL: 915.9ccs, operative time: 495 min. Ames BL classification: cSVA (53.2% minor deformity, 46.8% moderate), TS-CL (9.8% minor, 4.3% moderate, 85.9% marked), horizontal gaze (27.4% minor, 46.6% moderate, 26% marked). Relative to BL NDI (Mean: 47), normalized NDI decreased at 3-months (0.9 ± 0.5, p = 0.260) and 1Y (0.78 ± 0.41, p < 0.001). NDI IHS correlated with age (p = 0.011), gender (p = 0.042), anterior approach (p = 0.042), posterior approach(p = 0.042). Greater BL PT (SRK:25.6°, NRK:17°, p = 0.002), PI-LL (SRK:8.4°, NRK:-2.8°, p = 0.009), and anterior approach (SRK:34.8%, NRK:13.3%; p = 0.020) correlated with SRK. 69.4% met MCID for NDI(<Δ-15) and 63.3% met SCB for NDI(<Δ-10); 100% of SRK met both MCID and SCB. The predictive model for SRK included(AUC = 88.1%): BL VAS EQ5D(OR 0.96, CI:0.92-0.99), BL swallow sleep score(OR:1.04, CI:1.01-1.06), BL PT(OR:1.12, CI:1.03-1.22), BL mJOA (OR:1.5, CI:1.07-2.16), BL T4-T12, BL T10-L2, BL T12-S1 and BL L1-S1. CONCLUSIONS:Superior recovery kinetics following cervical deformity surgery was predicted with high accuracy using baseline patient reported (VAS EQ5D, swallow sleep, mJOA) and radiographic factors (PT, TK, T10-L2, T12-S1, L1-S1). Awareness of these factors can improve decision-making and reduce postoperative neck disability.Level of Evidence: 3.