Faculty Bibliography

INTRODUCTION/BACKGROUND:Osteoporosis affects nearly 200 million individuals worldwide. Given this notable disease burden, there have been increased efforts to investigate complications in patients with osteoporosis undergoing cervical fusion (CF). However, there are limited data regarding long-term outcomes in osteoporotic patients in the setting of ≥4-level cervical fusion. METHODS:The New York State Statewide Planning and Research Cooperative System database was used to identify patients who underwent posterior or combined anterior-posterior ≥4-level CF for cervical radiculopathy or myelopathy from 2009 to 2011, with a minimum follow-up surveillance of 2 years. The following were compared between patients with and without osteoporosis: demographics, hospital-related parameters, medical/surgical complications, readmissions, and revisions. Binary multivariate stepwise logistic regression was used to identify independent predictors of outcomes. RESULTS:A total of 2,604 patients were included (osteoporosis: n = 136 (5.2%); nonosteoporosis: n = 2,468). Patients with osteoporosis were older (66.9 ± 11.2 vs. 60.0 ± 11.4 years, P < 0.001), more often female (75.7% vs. 36.2%, P < 0.001), and White (80.0% vs. 65.3%, P = 0.007). Both cohorts had comparable comorbidity burdens (Charlson/Deyo: 1.1 ± 1.2 vs. 1.0 ± 1.3, P = 0.262), total hospital charges ($100,953 ± 94,933 vs. $91,618 ± 78,327, P = 0.181), and length of stay (9.7 ± 10.4 vs. 8.4 ± 9.6 days, P = 0.109). Patients with osteoporosis incurred higher rates of overall medical complication rates (41.9% vs. 29.4%, P = 0.002) and individual surgical complications, such as nonunion (2.9% vs. 0.7%, P = 0.006). Osteoporosis was associated with medical complications (OR = 1.57, P = 0.021), surgical complications (OR = 1.52, P = 0.030), and readmissions (OR = 1.86, P = 0.003) at 2 years. DISCUSSION/CONCLUSIONS:Among patients who underwent multilevel cervical fusion, those with osteoporosis had higher risk of adverse postoperative outcomes at two years. These data indicate that preoperative screening and management of osteoporosis may be important for optimizing long-term outcomes in patients who require multilevel CF. DATA AVAILABILITY AND TRIAL REGISTRATION NUMBERS/UNASSIGNED:The data used in this study are available for public use at https://www.health.ny.gov/statistics/sparcs/.

Study Design: Multicenter, prospective cohort Objectives: Malalignment following adult spine deformity (ASD) surgery can impact outcomes and increase mechanical complications. We assess whether preoperative goals for sagittal alignment following ASD surgery are achieved. Methods: ASD patients were prospectively enrolled based on 3 criteria: deformity severity (PI-LL ≥25°, TPA ≥30°, SVA ≥15 cm, TCobb≥70° or TLCobb≥50°), procedure complexity (≥12 levels fused, 3-CO or ACR) and/or age (>65 and ≥7 levels fused). The surgeon documented sagittal alignment goals prior to surgery. Goals were compared with achieved alignment on first follow-up standing radiographs. Results: The 266 enrolled patients had a mean age of 61.0 years (SD = 14.6) and 68% were women. Mean instrumented levels was 13.6 (SD = 3.8), and 23.2% had a 3-CO. Mean (SD) offsets (achieved-goal) were: SVA = −8.5 mm (45.6 mm), PI-LL = −4.6° (14.6°), TK = 7.2° (14.7°), reflecting tendencies to undercorrect SVA and PI-LL and increase TK. Goals were achieved for SVA, PI-LL, and TK in 74.4%, 71.4%, and 68.8% of patients, respectively, and was achieved for all 3 parameters in 37.2% of patients. Three factors were independently associated with achievement of all 3 alignment goals: use of PACs/equivalent for surgical planning (P <.001), lower baseline GCA (P =.009), and surgery not including a 3-CO (P =.037). Conclusions: Surgeons failed to achieve goal alignment of each sagittal parameter in ∼25-30% of ASD patients. Goal alignment for all 3 parameters was only achieved in 37.2% of patients. Those at greatest risk were patients with more severe deformity. Advancements are needed to enable more consistent translation of preoperative alignment goals to the operating room.

STUDY DESIGN/METHODS:Retrospective review of a multicenter comprehensive cervical deformity (CD) database. OBJECTIVE:To develop a novel risk index specific to each patient to aid in patient counseling and surgical planning to minimize postop DJK occurrence. BACKGROUND:Distal junctional kyphosis(DJK) is a radiographic finding identified after patients undergo instrumented spinal fusions which can result in sagittal spinal deformity, pain and disability, and potentially neurological compromise. DJK is considered multifactorial in nature and there is a lack of consensus on the true etiology of DJK. METHODS:CD pts with baseline(BL) and at least 1-year postoperative(1Y) radiographic follow-up were included. A patient-specific DJK score was created through use of unstandardized Beta weights of a multivariate regression model predicting DJK(end of fusion construct to the 2nd distal vertebra change in this angle by<-10° from BL to postop). RESULTS:110 CD pts included(61yrs, 66.4%F, 28.8kg/m2). 31.8% of these pts developed DJK (16.1% 3M, 11.4% 6M, 62.9% 1Y). At BL, DJK pts were more frail and underwent combined approach more (both P<0.05). Multivariate model regression analysis identified individualized scores through creation of a DJK equation: -0.55+0.009(BL Inclination) -0.078(Pre Inflection)+5.9×10-5(BL LIV angle) + 0.43(combine approach) - 0.002(BL TS-CL)- 0.002(BL PT)- 0.031(BL C2-C7)+ 0.02(∆T4-T12)+ 0.63(Osteoporosis)- 0.03(anterior approach) - 0.036( Frail) - 0.032(3 column osteotomy). This equation has a 77.8% accuracy of predicting DJK. A score ≥81 predicted DJK with an accuracy of 89.3%. The BL reference equation correlated with 2Y outcomes of NSR-Back percentage(P=0.003), reoperation(P=0.04), and MCID for EQ. 5D(P=0.04). CONCLUSIONS:This study proposes a novel risk index of DJK development that focuses on potentially modifiable surgical factors as well as established patient-related and radiographic determinants. The reference model created demonstrated strong correlations with relevant two year outcome measures, including axial pain-related symptoms, occurrence of related reoperations, and the achievement of minimal clinically importance differences for EQ. 5D.

PURPOSE/OBJECTIVE:To determine the proportions of patients returning to work at various points after adult spinal deformity (ASD) surgery and the associations between surgical invasiveness and time to return to work. METHODS:Using a multicenter database of patients treated surgically for ASD from 2008 to 2015, we identified 188 patients (mean age 51 ± 15 years) who self-reported as employed preoperatively and had 2-year follow-up. Per the ASD-Surgical and Radiographical Invasiveness Index (ASD-SR), 118 patients (63%) underwent high-invasiveness (HI) surgery (ASD-SR ≥ 100) and 70 (37%) had low-invasiveness (LI) surgery (ASD-SR < 100). Patients who self-reported ≥ 75% normal level of work/school activity were considered to be working full time. Chi-squared and Fisher exact tests were used to compare categorical variables (α = .05). RESULTS:Preoperatively, 69% of employed patients worked full time. Postoperatively, 15% of employed patients were full time at 6 weeks, 70% at 6 months, 83% at 1 year, and 84% at 2 years. Percentage of employed patients working full time at 2 years was greater than preoperatively (p < .001); percentage of patients returning to full time at 6 weeks was lower in the HI (5%) than in the LI group (19%) (p = .03), a difference not significant at later points. CONCLUSIONS:Most adults returned to full-time work after ASD surgery. A smaller percentage of patients in the HI group than in the LI group returned to full-time work at 6 weeks. Patients employed full time preoperatively will likely return to full-time employment after ASD surgery. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND/UNASSIGNED:Chiari malformation (CM) is a cluster of related developmental anomalies of the posterior fossa ranging from asymptomatic to fatal. Cranial and spinal decompression can help alleviate symptoms of increased cerebrospinal fluid pressure and correct spinal deformity. As surgical intervention for CM increases in frequency, understanding predictors of reoperation may help optimize neurosurgical planning. MATERIALS AND METHODS/UNASSIGNED:This was a retrospective analysis of the prospectively collected Healthcare Cost and Utilization Project's California State Inpatient Database years 2004-2011. Chiari malformation Types 1-4 (queried with ICD-9 CM codes) with associated spinal pathologies undergoing stand-alone spinal decompression (queried with ICD-9 CM procedure codes) were included. Cranial decompressions were excluded. RESULTS/UNASSIGNED:= 0.026). CONCLUSIONS/UNASSIGNED:Multiple medical and CM-specific comorbidities were associated with reoperation. Addressing them, where possible, may aid in improving CM surgery outcomes.

STUDY DESIGN/METHODS:Retrospective cohort. OBJECTIVE:To describe the 2-year outcomes for patients undergoing surgical correction of cervical deformity. BACKGROUND:Adult cervical deformity (CD) has been shown to compromise health-related quality of life. While advances in spinal realignment have shown promising short-term clinical results in this parameter, the long-term outcomes of CD corrective surgery remain unclear. METHODS:Operative CD patients >18 years with 2-year (2Y) HRQL/radiographic data were included. Improvement in radiographic, neurologic and HRQL outcomes were reported. Patients with a prior cervical fusion and patients with the greatest and smallest change based on NDI, NRS neck, mJOA were compared using multivariable analysis controlling for age, and frailty, and invasiveness. RESULTS:158 patients were included in this study. By 2Y, 96.3% of patients improved in Ames cSVA modifier, 34.2% in TS-CL, 42.0% in Horizontal gaze modifier, and 40.9% in SVA modifier. Additionally, 65.5% of patients improved in Passias CL modifier, 53.3% in TS-CL modifier, 100% in C2-T3 modifier, 88.9% in C2S modifier, and 81.0% in MGS modifier severity by 2Y. The cohort significantly improved from BL to 2Y in NDI, NRS Neck, and mJOA, all P<0.05. 59.3% of patients met MCID for NDI, 62.3% for NRS Neck, and 37.3% for mJOA. 97 patients presented with at least one neurologic deficit at BL and 63.9% no longer reported that deficit at follow-up. There were 45 (34.6%) cases of DJK (∆DJKA>10° between LIV and LIV-2), of which 17 were distal junctional failure (DJF-DJK requiring reoperation). Patients with the greatest beneficial change were less likely to have had a complication in the 2-year follow-up period. CONCLUSION/CONCLUSIONS:Correction of cervical deformity results in notable clinical and radiographic improvement with most patients achieving favorable outcomes after two years. However, complications including distal junctional kyphosis or failure remain prevalent.

BACKGROUND:Studies have utilized psychological questionnaires to identify the psychological distress among certain surgical populations. RESEARCH QUESTION/OBJECTIVE:Is there an additional psychological burden among patients undergoing surgical treatment for their symptomatic degenerative cervical disease? MATERIALS AND METHODS/METHODS:Patients>18 years of age with symptomatic, degenerative cervical spine disease were included and prospectively enrolled. Correlations and multivariable logistic regression analysis assessed the relationship between these mental health components (PCS, FABQ) and the severity of disability described by the NDI, EQ-5D, and mJOA score. Patient distress scores were compared to previously published benchmarks for other diagnoses. RESULTS:). Increasing neck disability and decreasing EQ-5D were correlated with greater PCS and FABQ(all p<0.001). Patients with severe psychological distress at baseline were more likely to report severe neck disability, while physician-reported mJOA had weaker associations. Compared to historical controls of lumbar patients, patients in our study had greater levels of psychological distress, as measured by FABQ (40.0 vs 17.6;p<0.001) and PCS (27.4 vs 19.3;p<0.001). DISCUSSION AND CONCLUSION/CONCLUSIONS:Degenerative cervical spine patients seeking surgery were found to have a significant level of psychological distress, with a large portion reporting severe fear avoidance beliefs and catastrophizing pain at baseline. Strong correlation was seen between patient-reported functional metrics, but less so with physician-reported signs and symptoms. Additionally, this population demonstrated higher psychological burden in certain respects than previously identified benchmarks of patients with other disorders. Preoperative treatment to help mitigate this distress, impact postoperative outcomes, and should be further investigated. LEVEL OF EVIDENCE/METHODS:Level III.

BACKGROUND:As corrective surgery for cervical deformity (CD) increases, so does the rate of complications and reoperations. To minimize suboptimal postoperative outcomes, it is important to develop a tool that allows for proper preoperative risk stratification. OBJECTIVE:To develop a prognostic utility for identification of risk factors that lead to the development of major complications and unplanned reoperations. METHODS:CD patients age 18 years or older were stratified into 2 groups based on the postoperative occurrence of a revision and/or major complication. Multivariable logistic regressions identified characteristics that were associated with revision or major complication. Decision tree analysis established cutoffs for predictive variables. Models predicting both outcomes were quantified using area under the curve (AUC) and receiver operating curve characteristics. RESULTS:A total of 109 patients with CD were included in this study. By 1 year postoperatively, 26 patients experienced a major complication and 17 patients underwent a revision. Predictive modeling incorporating preoperative and surgical factors identified development of a revision to include upper instrumented vertebrae > C5, lowermost instrumented vertebrae > T7, number of unfused lordotic cervical vertebrae > 1, baseline T1 slope > 25.3°, and number of vertebral levels in maximal kyphosis > 12 (AUC: 0.82). For developing a major complication, a model included a current smoking history, osteoporosis, upper instrumented vertebrae inclination angle < 0° or > 40°, anterior diskectomies > 3, and a posterior Smith Peterson osteotomy (AUC: 0.81). CONCLUSION/CONCLUSIONS:Revisions were predicted using a predominance of radiographic parameters while the occurrence of major complications relied on baseline bone health, radiographic, and surgical characteristics.

STUDY DESIGN/METHODS:Retrospective cohort study. OBJECTIVE:Assess changes in outcomes and surgical approaches for adult cervical deformity (ACD) surgery over time. SUMMARY OF BACKGROUND DATA/BACKGROUND:As the population ages and prevalence of cervical deformity increases, corrective surgery has been increasingly seen as a viable treatment. Dramatic surgical advancements and expansion of knowledge on this procedure have transpired over years, but the impact on cervical deformity surgery is unknown. METHODS:ACD patients (≥18 yrs) with complete baseline and up to two-year HRQL and radiographic data were included. Descriptive analysis included demographics, radiographic, and surgical details. Patients were grouped into Early(2013-2014) and Late(2015-2017) by DOS. Univariate and multivariable regression analyses were used to assess differences in surgical, radiographic, and clinical outcomes over time. RESULTS:119 cervical deformity patients met inclusion criteria. Early group consisted of 72 patients, and Late group consisted of 47. Late group had a higher CCI (1.3 vs. 0.72), more cerebrovascular disease (6% vs. 0%, both P<0.05), and no difference in age, frailty, deformity, or cervical rigidity. Controlling for baseline deformity, and age, Late group underwent fewer three-column osteotomies (OR=0.18, 95% CI:0.06-0.76, P=0.014). At last follow-up, Late group had less patients with: a moderate/high Ames horizontal modifier (71.7% vs. 88.2%), and overcorrection in PT (4.3% vs. 18.1%, both P<0.05). Controlling for baseline deformity, age, levels fused, and three-column osteotomies, Late group experienced fewer adverse events (OR =0.15, 95% CI: 0.28-0.8, P=0.03), and neurological complications (OR =0.1, 95% CI:0.012-0.87, P=0.03). CONCLUSION/CONCLUSIONS:Despite a population with greater co-morbidity and associated risk, outcomes remained consistent between early and later time-periods, indicating general improvements in care. The later cohort demonstrated fewer three-column osteotomies, less suboptimal realignments and concomitant reductions in adverse events and neurologic complications. This may suggest greater facility with less invasive techniques.

BACKGROUND:Three-column osteotomies (3COs), usually in the form of pedicle subtraction or vertebral column resection, have become common in adult spinal deformity surgery. Although a powerful tool for deformity correction, 3COs can increase the risks of perioperative morbidity. METHODS:Operative patients with adult spinal deformity (Cobb angle of >20°, sagittal vertical axis [SVA] of >5 cm, pelvic tilt of >25°, and/or thoracic kyphosis of >60°) with available baseline and 2-year radiographic and health-related quality-of-life (HRQoL) data were included. Patients were stratified into 2 groups by surgical year: Group I (2008 to 2013) and Group II (2014 to 2018). Patients with 3COs were then isolated for outcomes analysis. Severe sagittal deformity was defined by an SVA of >9.5 cm. Best clinical outcome (BCO) was defined as an Oswestry Disability Index (ODI) of <15 and Scoliosis Research Society (SRS)-22 of >4.5. Multivariable regression analyses were used to assess differences in surgical, radiographic, and clinical parameters. RESULTS:Seven hundred and fifty-two patients with adult spinal deformity met the inclusion criteria, and 138 patients underwent a 3CO. Controlling for baseline SVA, PI-LL (pelvic incidence minus lumbar lordosis), revision status, age, and Charlson Comorbidity Index (CCI), Group II was less likely than Group I to have a 3CO (21% versus 31%; odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.97) and more likely to have an anterior lumbar interbody fusion (ALIF; OR = 1.6; 95% CI = 1.3 to 2.3) and a lateral lumbar interbody fusion (LLIF; OR = 3.8; 95% CI = 2.3 to 6.2). Adjusted analyses showed that Group II had a higher likelihood of supplemental rod usage (OR = 21.8; 95% CI = 7.8 to 61) and a lower likelihood of proximal junctional failure (PJF; OR = 0.23; 95% CI = 0.07 to 0.76) and overall hardware complications by 2 years (OR = 0.28; 95% CI = 0.1 to 0.8). In an adjusted analysis, Group II had a higher likelihood of titanium rod usage (OR = 2.7; 95% CI = 1.03 to 7.2). Group II had a lower 2-year ODI and higher scores on Short Form (SF)-36 components and SRS-22 total (p < 0.05 for all). Controlling for baseline ODI, Group II was more likely to reach the BCO for the ODI (OR = 2.8; 95% CI = 1.2 to 6.4) and the SRS-22 total score (OR = 4.6; 95% CI = 1.3 to 16). CONCLUSIONS:Over a 10-year period, the rates of 3CO usage declined, including in cases of severe deformity, with an increase in the usage of PJF prophylaxis. A better understanding of the utility of 3CO, along with a greater implementation of preventive measures, has led to a decrease in complications and PJF and a significant improvement in patient-reported outcome measures. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.