Faculty Bibliography

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.

BACKGROUND:Frailty is influential in determining operative outcomes, including complications, in patients with cervical deformity (CD). OBJECTIVE:To assess whether frailty status limits the highest achievable outcomes of patients with CD. METHODS:Adult patients with CD with 2-year (2Y) data included. Frailty stratification: not frail (NF) <0.2, frail (F) 0.2 to 0.4, and severely frail (SF) >0.4. Analysis of covariance established estimated marginal means based on age, invasiveness, and baseline deformity, for improvement, deterioration, or maintenance in Neck Disability Index (NDI), Modified Japanese Orthopaedic Association (mJOA), and Numerical Rating Scale Neck Pain. RESULTS:One hundred twenty-six patients with CD included 29 NF, 83 F, and 14 SF. The NF group had the highest rates of deterioration and lowest rates of improvement in cervical Sagittal Vertical Axis and horizontal gaze modifiers. Two-year improvements in NDI by frailty: NF: -11.2, F: -16.9, and SF: -14.6 (P = .524). The top quartile of NF patients also had the lowest 1-year (1Y) NDI (7.0) compared with F (11.0) and SF (40.5). Between 1Y and 2Y, 7.9% of patients deteriorated in NDI, 71.1% maintained, and 21.1% improved. Between 1Y and 2Y, SF had the highest rate of improvement (42%), while NF had the highest rate of deterioration (18.5%). CONCLUSION/CONCLUSIONS:Although frail patients improved more often by 1Y, SF patients achieve most of their clinical improvement between 1 and 2Y. Frailty is associated with factors such as osteoporosis, poor alignment, neurological status, sarcopenia, and other medical comorbidities. Similarly, clinical outcomes can be affected by many factors (fusion status, number of pain generators within treated levels, integrity of soft tissues and bone, and deformity correction). Although accounting for such factors will ultimately determine whether frailty alone is an independent risk factor, these preliminary findings may suggest that frailty status affects the clinical outcomes and improvement after CD surgery.

Vertebral osteomyelitis (VOM), which includes the clinical entities of spinal osteomyelitis, spondylodiscitis, or pyogenic spondylitis, describes a complex inflammatory reaction within the vertebral column in the setting of microbial infection [...].

STUDY DESIGN/METHODS: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/BACKGROUND: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/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 χ2 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.

AIMS/OBJECTIVE:Postoperative complication rates remain relatively high after adult spinal deformity (ASD) surgery. The extent to which modifiable patient-related factors influence complication rates in patients with ASD has not been effectively evaluated. The aim of this retrospective cohort study was to evaluate the association between modifiable patient-related factors and complications after corrective surgery for ASD. METHODS:ASD patients with two-year data were included. Complications were categorized as follows: any complication, major, medical, surgical, major mechanical, major radiological, and reoperation. Modifiable risk factors included smoking, obesity, osteoporosis, alcohol use, depression, psychiatric diagnosis, and hypertension. Patients were stratified by the degree of baseline deformity (low degree of deformity (LowDef)/high degree of deformity (HighDef): below or above 20°) and age (Older/Younger: above or below 65 years). Complication rates were compared for modifiable risk factors in each age/deformity group, using multivariable logistic regression analysis to adjust for confounders. RESULTS:A total of 480 ASD patients met the inclusion criteria. By two years, complication rates were 72% ≥ one complication, 28% major, 21% medical, 27% surgical, 11% major radiological, 8% major mechanical, and 22% required reoperation. Younger LowDef patients with osteoporosis were more likely to suffer either a major mechanical (odds ratio (OR) 5.9 (95% confidence interval (CI) 1.1 to 36.9); p = 0.048) or radiological complication (OR 7.0 (95% CI 1.9 to 25.9); p = 0.003). Younger HighDef patients were much more likely to develop complications if obese, especially major mechanical complications (OR 2.8 (95% CI 1.1 to 8.6); p = 0.044). Older HighDef patients developed more complications when diagnosed with depression, including major radiological complications (OR 3.5 (95% CI 1.1 to 10.6); p = 0.033). Overall, a diagnosis of depression proved to be a risk factor for the development of major radiological complications (OR 2.4 (95% CI 1.3 to 4.5); p = 0.005). CONCLUSION/CONCLUSIONS: 2022;104-B(11):1249-1255.

STUDY DESIGN/METHODS:Retrospective single-center, consecutively enrolled database of adult spinal deformity (ASD) patients. OBJECTIVE:To assess the performance of the mASD-FI in predicting clinical and patient-reported outcomes after ASD-corrective surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:The recently described modified Adult Spinal Deformity frailty index (mASD-FI) quantifies frailty of ASD patients, but the utility of this clinical prediction tool as a means of prognosticating postoperative outcomes has not been investigated. METHODS:ASD patients with available mASD-FI scores and HRQL data at presentation and 2-years postop were included. Patients were stratified by mASD-FI score using published cutoffs: not frail (NF,<7), frail (F,7-12), severely frail (SF,>12). ANOVA assessed differences in patient factors across frailty groups. Linear regression assessed the relationship of mASD-FI with length of stay(LOS) and HRQLs. Multivariable logistic regression revealed how frailty category predicted odds of complications, infections and reoperation. RESULTS:509 pts included (59yrs, 79%F, 27.7 kg/m2). The cohort presented with moderate baseline deformity: SVA (83.7mm±71), PT (12.7°±10.8), PI-LL (43.1°±21.1). Mean preoperative mASD-FI score was 7.2, frailty category: NF (50.3%), F (34.0%), SF (15.7%). Age, BMI, and CCI increased with frailty categories (all p < 0.001); however, fusion length (p = 0.247) and osteotomy rate (p = 0.731) did not. At baseline, increasing frailty was associated with inferior ODI, EQ-5D, SRS-22r, PCS, and NRS Back and Leg (all p < 0.001). Greater frailty was associated with increased LOS and reduced postoperative HRQL. Controlling for complication incidence, baseline mASD-FI predicted 2 year postop scores for year ODI (b = 0.7, 0.58-0.8, p < 0.001) SRS (b = -0.023, -0.03 - -0.02, p < 0.001), EQ-5D (b = -0.003, -0.004 - -0.002, p < 0.001). F and SF were associated with greater odds of unplanned revision surgery and complications. CONCLUSION/CONCLUSIONS:Higher preoperative mASD-FI score was associated with significantly greater complications, higher rate of unplanned reoperations and lower postoperative HRQL in this investigation. The mASD-FI provides similar prognostic utility while reducing burden for surgeons and patients.

SUMMARY OF BACKGROUND DATA/BACKGROUND:The influence of frailty on economic burden following corrective surgery for adult cervical deformity (CD) is understudied and may provide valuable insights for pre-operative planning. OBJECTIVE:To assess the influence of baseline frailty status on the economic burden of CD surgery. STUDY DESIGN/METHODS:Retrospective cohort. METHODS:CD patients with frailty scores and baseline (BL) and 2-year (2Y) NDI data were included. Frailty score was categorized patients by mFI-CD into Not Frail (NF) and Frail (F). ANCOVA was used to estimate marginal means adjusting for age, sex, surgical approach, and baseline Sacral Slope, TS-CL, C2-C7 angle, cSVA. Costs were derived from PearlDiver registry data. Reimbursement consisted of a standardized estimate using regression analysis of Medicare pay-scales for services within a 30-day window including length of stay and death. This data is representative of national average Medicare cost differentiated by complication/comorbidity outcome, surgical approach, and revision status. Cost per Quality-Adjusted Life Year (QALY) at 2Y was calculated for NF and F patients. RESULTS:There were 126 patients included. There were 68 Not Frail patients and 58 classified as Frail (F). Frailty groups did not differ by overall complications, instance of distal junctional kyphosis, or reoperations (all P>0.05). These groups had similar rates of radiographic and clinical improvement by two years. NF and F had similar overall cost ($36,731.03 vs. $37,356.75, P=0.793), resulting in equivocal costs per QALYs for both patients at 2Y ($90,113.79 vs. $80,866.66, P=0.097). CONCLUSION/CONCLUSIONS:Frail and not frail patients experienced similar complication rates and upfront costs, with equivocal utility gained, leading to a comparative cost effectiveness with non-frail patients based on cost per QALYs at two years. Surgical correction for cervical deformity is an economical healthcare investment for frail patients, when accounting for anticipated utility gained and cost-effectiveness following the procedure. LEVEL OF EVIDENCE/METHODS:III.

STUDY DESIGN/SETTING/METHODS:Retrospective cohort. OBJECTIVE:Adult spinal deformity (ASD) corrective surgery is often a highly invasive procedure portending patients to both immediate and long-term complications. Therefore, we sought to compare the economic impact of certain complications before and after 2 years. METHODS:2 years postoperatively. Published methods converted ODI to SF-6D to QALYs. Cost was calculated using CMS.gov definitions. Marginalized means for utility gained and cost-per-QALY were calculated via ANCOVA controlling for significant confounders. RESULTS:2 years. CONCLUSION/CONCLUSIONS:Mechanical complications had the single greatest impact on cost-utility after adult spinal deformity surgery, but less so after 2 years. Understanding the cost-utility of specific interventions at certain timepoints may mitigate economic burden and prophylactic efforts should strategically be made against early mechanical complications.

BACKGROUND CONTEXT: It is imperative to determine which factors have greater implications on postoperative outcomes, which can afford tailored treatment plans for adult spinal deformity (ASD) patients. PURPOSE: To determine the discriminative ability of commonly used indices to predict adverse outcomes after corrective surgery for adult spinal deformity. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: This study included 9,763 patients. OUTCOME MEASURES: Perioperative complications.
METHOD(S): ASD patients from the National Surgical Quality Improvement Program (NSQIP) 2005-2015 were included. Logistic regression analysis determined significant odds ratios among complications between the following indices and demographics: Passias et al modified frailty index score for ASD (mFI-ASD), the modified Charlson Comorbidity Index (mCCI), ASA classification score, age and body mass index (BMI). Using multivariate analysis, indices and demographics that demonstrated significance for predicting complications were identified. CIT run forest analysis generated an index threshold value for all complications tested.
RESULT(S): Included: 9,763 ASD patients. At least 4 of the 5 risk indices were significant for the following complications: any type, major, cardiac, infection and death. None of the indices correlated with reoperation or readmission. The mFI-ASD demonstrated the highest odds ratio (OR) for all complications (p <.001), followed by ASA status. Modified CCI also correlated with a higher OR for all five complications, compared to age and BMI. An index threshold value for each complication was determined by CIT run forest analysis. Analysis of threshold values showed mFI had the highest ORs for any complication (OR: 3.50) as well as infection (OR: 2.53). ASA status, on the other hand, had the highest ORs for major complications (OR: 2.93), cardiac complications (OR: 4.09) and death (OR: 10.18).
CONCLUSION(S): The modified FI-ASD demonstrated superiority in predicting adverse postoperative outcomes, compared to various commonly used indices and patient characteristics. These findings are important as it allows spine surgeons to appropriately counsel their patients preoperatively. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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