Faculty Bibliography

BACKGROUND CONTEXT: Adult spinal deformity (ASD) surgery is complex and may lead to new-onset cervical malalignment and/or proximal junctional kyphosis (PJK). Roussouly et al describes variations in baseline thoracolumbar (TL) shape (Types 1-4), which have been shown to differentially influence surgical ASD outcomes. The effect of morphological shape on patterns of postoperative CD development remains underexplored. PURPOSE: Stratify patients by Roussouly type and assess patterns of conversion from baseline (BL) cervical alignment to postoperative cervical deformity (CD) in patients undergoing thoracolumbar ASD surgery. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter database of ASD patients. PATIENT SAMPLE: A total of 266 surgical ASD patients. OUTCOME MEASURES: Rate and timing of conversion to CD, rate of PJK, radiographic alignment parameters.
METHOD(S): Operative ASD patients with complete radiographic data at baseline, 6W, 1Y, 2Y, & 3Y intervals were included. Patients were grouped by baseline PI and apex of LL into component types of the Roussouly classification system utilizing pelvic incidence as published by Pizones et al. Patients with no BL CD were postoperatively stratified by Ames CD criteria (TS-CL>20 degree, cSVA>40mm), where CD was defined as fulfilling >1 criteria. Follow-up intervals were established post-ASD surgery, with 6W postop defined as "Early," 6W-1Y "Intermediate," 1-2Y "Late," and 2-3Y "Long." Univariate and Cox regression analyses identified CD conversion rate and PJK rate (<-10degree change in UIV and UIV+2) across Roussouly types 1-4.
RESULT(S): A total of 266 surgical ASD patients (59.7yrs, 77.4% F) with complete radiographic data were included. By Roussouly classification, 9% were Type 1, 15.8% Type 2, 46.6% Type 3, and 28.6% Type 4. 28.6% of ASD patients converted to postop CD (Early: 14.3%, Intermediate: 5.3%, Late: 4.1%, Long: 4.9%). There were no significant differences in CD conversion rate across Roussouly types (1: 33.3%; 2: 28.6%; 3: 26.6%; 4: 30.3%, P=0.895). Types 2 (41.7%), 3 (60.6%), and 4 (43.5%) had their peak rates of conversion in the Early (<6w) window compared to other follow-up intervals, whereas Type 1 patients had a peak rate (50%) between 6w-1Y. Type 2 patients had higher rates of later CD conversion (>1 year) than other types (50% vs 28.1%, P=0.135), while Type 1 patients trended higher rates of earlier CD conversion (<1 year) than other types (33.8% vs 12.5%, P=0.220); these patterns did not reach statistical significance. Across Roussouly Types, among patients who converted to CD, Type 4 had significantly higher rates of ++ SRS-Schwab PT and greater TPA at BL (both p<0.05). Type 4 patients had the highest rate of concurrent PJK with CD conversion (60.9%) compared to Type 1 (50%), Type 2 (50%), or Type 3 (54.5%) (P>0.05). There were no significant change in ODI, PCS, or SRS total among Roussouly Types in patients that converted to CD (p>0.05). Random forest analysis determined the top surgical (levels fused), radiographic (TS-CL), and demographic (frailty) factors associated with CD conversion.
CONCLUSION(S): Baseline thoracolumbar shape as described by the Roussouly classification has a differential effect on timing to CD conversion, though overall rates of CD conversion after TL-ASD correction were similar across Types 1-4. Type 1 patients with a lower apex of lumbar lordosis trended earlier conversion, while Type 2 patients with a higher apex of LL trended conversion beyond 1-year postop. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: To make the 40-factor adult spinal deformity frailty index (ASD-FI) more practical for use in clinical setting, a recent study proposed a modified, 8-factor frailty index (mASD-FI). The mASD-FI quantifies frailty of ASD patients on a scale from 0 to 21, with higher scores indicating greater frailty. While the mASD-FI has been shown to correlate with preoperative pain and disability, its relationship with postoperative outcomes has not been investigated. PURPOSE: Assess the relationship between mASD-FI score and clinical outcomes after ASD-corrective surgery. STUDY DESIGN/SETTING: Retrospective cohort study PATIENT SAMPLE: A total of 509 ASD patients OUTCOME MEASURES: Length of stay (LOS), complications, health-related quality of life (HRQL) questionnaires: ODI, SRS-22r, EQ-5D, SF-36 Physical Component Score (PCS).
METHOD(S): ASD patients (scoliosis>=20degree, SVA>=5cm, PT>=25degree, or TK >=60degree) with available mASD-FI scores and HRQL data at pre- and 2-years postop intervals were included. Patients were stratified by mASD-FI score using published cutoffs: not frail (<7), frail (7-12), severely frail (>12). Analysis of variance (ANOVA) assessed differences in demographics, surgical factors, and HRQL across frailty groups. Linear regression assessed the relationship between mASD-FI score and postop clinical outcomes (LOS, HRQL scores). Binary logistic regression assessed the relationship between frailty category and odds of complication or reoperation (results presented: odds ratio [95% confidence interval]).
RESULT(S): A total of 509 ASD patients were included (59+/-14yrs, 79%F, BMI: 27.7+/-6.0 kg/m2). The overall cohort presented with moderate baseline deformity: SVA (83.7mm+/-71), PT (12.7degree+/-10.8), PI-LL (43.1degree+/-21.1). Mean preop mASD-FI score was 7.2+/-5.0, and breakdown by frailty category was: not frail (50.3%), frail (34.0%), severely frail (15.7%). Preop age, BMI, and Charlson Comorbidity Index score all increased across increasing frailty categories (all p<0.001); however, fusion length (p=0.247) and rates of osteotomy (p=0.731) did not. At baseline, increasing frailty was associated with inferior ODI, EQ-5D, SRS-22r, SF-36 PCS, and NRS Back and Leg pain scores (all p<0.001). Following surgery, length of stay increased with increasing frailty category (6.9 days, 7.9 days, 9.6 days, p<0.001). Complication rates increased with frailty (57.6%, 64.4%, 78.7%, p<0.001). Increasing frailty was also associated with inferior postoperative outcomes for ODI (19.9, 31.8, 41.2), SRS (3.9, 3.6, 3.2), EQ-5D (0.84, 0.80, 0.74), and SF-36 PCS (44.2, 36.5, 32.6, all p<0.001). Higher preop mASD-FI scores predicted inferior postoperative scores for ODI (R2=0.193), SRS (R2=0.132), EQ-5D (R2=0.156) and SF-36 (R2=0.198). Controlling for complication incidence, baseline mASD-FI score still predicted postop scores for ODI, SRS, EQ-5D, and SF-36 (all p<0.001). Frailty also predicted higher odds of revision surgery (1.6 [1.1-2.5]) and complication (2.2 [1.5-3.2]), including infection (2.1 [1.1-3.9]), wound (2.0 [1.3-3.0]), and implant-related (2.2 [1.4-3.5]) complications. Severe frailty was associated with even greater odds of revision (2.0 [1.1-3.4]) and complication (2.8 [1.5-5.0]), including infection (2.5 [1.3-5.0]) and radiographic (2.3 [1.4-3.8]) complications. Operative treatment was associated with significant pre- to postop changes in frailty (7.2+/-5.0 to 4.9+/-4.4, p<0.001).
CONCLUSION(S): Greater preoperative frailty, as assessed by mASD-FI score, was associated with significantly greater LOS and inferior postoperative health-related quality of life across multiple outcomes assessment instruments. Frailty status was associated with increased odds of reoperation, complication, and infection. Severely frail patients showed the greatest risk of experiencing an adverse event. These results suggest the mASD-FI may have utility as a preoperative risk assessment tool. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Metabolic (Met) syndrome is an amalgamation of medical disorders that ultimately increase patient complications. Factors such as obesity, hypertension, dyslipidemia and hyperglycemic are associated with this disease complex (two or more factors). PURPOSE: Assess the incremental value of improving Met syndrome in relation to clinical outcomes. STUDY DESIGN/SETTING: Retrospective cohort study of patients with metabolic syndrome through the use of the Nationwide Inpatient Sample (NIS) years 2007-16. PATIENT SAMPLE: Elective spine surgery patients with >2 metabolic syndrome criteria. OUTCOME MEASURES: Complications.
METHOD(S): Pts undergoing elective spine surgery were isolated in NIS 2007-2016. Spine patients were then separated into two groups: metabolic syndrome patients (>2 metabolic variables: hypertension, diabetes, obesity, and triglycerides) and non-metabolic patients (<2 metabolic variables). T-tests and chi-squared tests compared differences in pts demographics. Resolution of metabolic factors were incrementally analyzed for their effect on perioperative complications through utilization of logistic regressions.
RESULT(S): A total of 2,855,517 elective spine pts were included and 20.1% had metabolic syndrome (81.4% 2 factors, 18.4% 3 factors, 0.2% 4 factors). Met pts were older, less female, and more comorbid (p<0.001). Among the metabolic patients, the most common metabolic variable was hypertension (95.9%), blood sugar (72.4%), obesity (48.9%), and triglycerides/HDL (1.8%). A total of 28.8% Met pts developed more complications such as anemia (9.8% vs 5.9%), device-related (3.5% vs 2.9%), neurologic (2.3% vs 1.4%), and bowel issues (9.7% vs 6.8%; p<0.05). Controlling for age and invasiveness, having 3 Met factors increased a PT's likelihood (0.89x) of developing a perioperative complication (p<0.05) whereas 2 factors had lower odds (0.82). More specifically, pts that were hyperglycemic, obese, and had hypertension had the greatest odds at developing a complication (0.58 [0.58-0.57]) followed by those that had concomitant hypertension, high triglycerides, and were obese (0.55[0.63-0.48]; all p<0.001). Met pts with 2 factors, being obese and having hypertension produced the lowest odds at developing a complication (0.5[0.61-0.43;p<0.001). These Met pts also had a lower length of stay than those with 3 and 4 (p<0.001).
CONCLUSION(S): Metabolic patients improved in perioperative complications incrementally, demonstrating the utility of efforts to mitigate burden of metabolic syndrome even if not completed abolished. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Frailty is an increasingly recognized characteristic that has been validated across many studies as influencing operative risk. Utilization of frailty indices can allow for its identification of which spine patients may be too high risk for surgical intervention. This may be especially useful when it comes to surgeries that are minimally invasive and are supposed to have decrease perioperative outcomes. PURPOSE: Identify MIS techniques effects in postoperative outcomes in TLIF patients. STUDY DESIGN/SETTING: Retrospective review of a prospective database. PATIENT SAMPLE: TLIF spine patients. OUTCOME MEASURES: Complications, length of stay (LOS), estimated blood loss (EBL).
METHOD(S): Pts that underwent a lumbar spine procedure in a single-center Comprehensive Spine Quality Database. Pts were stratified based on procedural approach (Open [OP] and Minimally invasive Surgery [MIS]). Frailty was then calculated for each resultant group by using 30 variables with a validated method. Based on these scores, pts were categorized no frailty [NF]: <0.09, frail [F]: 0.09-0.18, and severe frailty [SF] >0.18. Groups were then controlled for surgical invasiveness. Chi-squared tests identified the relationship between complications and length of stay among various frailty states given surgical approach (OP vs MIS). These patients were propensity score matched for levels fused. Hospital acquired complications (HACs) were identified based on frailty groups through the use of chi-squared and t-tests for other surgical factors. A logistic regression analysis identified the association between frailty status and surgical, regarding postoperative (postop) outcomes.
RESULT(S): A total of 1,300 TLIF spine patients were isolated (59yrs, 29.3kg/m2). After PSM for levels fused, there were 338 pts for both MIS and OP. MIS pts were older (56.1 vs 53.3; p<0.05) than Op pts and had similar BMI's (29.1 vs 29.7; respectively). However, OP received more posterior approaches and less anterior approaches than MIS pts (p<0.05). By surgical factors: MIS and OP patients had similar LOS (3 vs 2.9days) and EBL (282.8 vs 251.5cc) but differed by Op time (195.7 vs 247.1; p<0.05) respectively. Further breakdown by frailty displayed statistical significance between MIS and OP patients with MIS pts having more F (16% vs 12%) and SF pts (4.3% vs 1.9%) than OP (all p<0.05). FMIS patients had lower postop neurologic complications as compared to FOP pts (4.63% vs 14.8%). However, SFMIS patiens had more post-operative complications than SFOP pts (55.2% vs 23.1%) and increased a pt's likelihood of being SFMIS by 5.4x's (all p<0.05).
CONCLUSION(S): This study displays that when frailty status is taken into account, TLIF MIS patients benefit from this procedure type when analyzed against neurologic complications. However, these patients were seen to suffer more from postop complications but did not differ on any other specific complications or surgical variables. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Cervical deformity (CD) severity has been linked to poor quality of life and severe neck pain. However, little is known of the relationship between surgical invasiveness accounting for cervical deformity severity and frailty status. PURPOSE: Investigate the outcomes of CD surgery by invasiveness, frailty status and baseline degree of deformity. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Ninety-six CD patients. OUTCOME MEASURES: HRQL measurements: NDI, EQ5D, mJOA.
METHOD(S): Inclusion criteria was defined as operative CD patients (C2-C7 Cobb>10degreeor CK>10degree, cSVA>4cm or CBVA>25degree) >18yr with follow up (1-year) radiographic and HRQL scores, NDI, mJOA and EQ5D. Patients were stratified by severity of deformity by TS-CL, categorized by the new-mJOA based modifiers: Low/Mod <45degree (Low-Mod); Severe >45degree(Sev). Frailty scores were calculated based upon the modified CD frailty index by Passias et. Al and categorized into severely frail (SF) >=0.5 and not SF (N-SF)<0.5. Patients were categorized by their frailty and deformity status (Low-Mod/N-SF; Low-Mod/SF; Sev/N-SF; Sev/SF). Logistic regression analysis assessed the relationship between increasing invasiveness and outcomes (DJK, complications). Within the significant frailty/deformity risk groups, decision tree analysis assessed thresholds for an invasiveness severity cut-off point, below which experiencing a reoperation, complication, DJK occurrence and poor mJOA were higher.
RESULT(S): Ninety-six CD patients met inclusion criteria (62.2+/-10.2 years, 66% female, 28.4+/-7.4 kg/m2). By approach: 19.8% anterior-only, 47.9% posterior-only, 32.3% combined (levels fused: 7.7+/-3.9). By deformity severity: 23.7% Low, 40.9% Moderate, 34.4% Severe, while frailty assessment placed 32.3% in N-SF and 67.7% SF. This categorized the patients into deformity/frailty groups as follows: 19.8% Low-Mod/N-SF(19), 13.5%(13) Sev/N-SF, 44.8%(43) Low-Mod/SF, 21.9%(21) Sev/SF. Logistic regression analysis found a significant relationship between increasing deformity severity and occurrence of severe postop DJK(1.053 [1.016-1.093], p= 0.005), complications(1.045 [1.012 - 1.080], p=0.007), revision by 1-year(1.059 [1.000-1.122], p= 0.049). Additionally, increasing invasiveness and occurrence of severe DJK (1.030 [1.007-1.054], p= 0.024) and revision (1.026 [1.008 - 1.044], p=0.005). Invasiveness increased with deformity and frailty severity: 53.6 Low-Mod/N-SF, 81.4 Sev/N-SF, 56.4 Low-Mod/SF, 79.8 Sev/SF; p=0.002. After defining a favorable outcome as no occurrence of severe DJK, no major complications and no revisions, and 1Y mJOA improvement (28.1%), invasiveness scores were compared within deformity/frailty groups between patients who met/did not meet the favorable outcome. For the NSF deformity groups, those with a favorable outcome had larger invasiveness scores (Low-Mod: 58.7 vs 48.5; Sev: 77.7 vs 89.6). For the SF deformity groups, the favorable outcome had significantly lower invasiveness scores for the Low-Mod deformity group (38.1 vs 62.9, p=0.008), while the Sev/SF deformity favorable outcome group remained larger (86.8 vs 79.4), though this was not significant. For the Low-Mod/SF group an invasiveness cutoff score of <48 where achieving a favorable outcome was 3x higher (3.08[1.2-7.9], p=0.019).
CONCLUSION(S): For SF patients, when deformity severity is low to moderate, surgeons may limit the invasiveness of their procedures in order to account for the patient's susceptibility to poor outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Adult spinal deformity (ASD) correction involves complex, invasive procedures. However, it is unknown how metabolic syndrome affects the cost efficiency of ASD surgery. PURPOSE: Investigate the differences in ASD surgery cost for metabolic syndrome patients. STUDY DESIGN/SETTING: Retrospective review of a single center ASD database. PATIENT SAMPLE: A total of 557 ASD patients. OUTCOME MEASURES: Complications, revisions and costs.
METHOD(S): ASD patients (scoliosis >=20degree, SVA>=5cm, PT >=25degree, or TK >=60degree) >=18, undergoing >=4 level fusions were included. Descriptive analysis assessed mean baseline demographic, radiographic and surgical data were assessed. Patients diagnosed with: BMI >30, diabetes mellitus, and HTN were classified metabolic syndrome patients (MetS). Independent samples T-tests assessed baseline differences in SVA, PT, PI-LL, and levels fused between MetS and non-MetS patients. Total surgery costs for MetS and non-MetS ASD patients were compared. Costs were calculated using the PearlDiver database, which reflects both private insurance and Medicare reimbursement claims. Complications and comorbidities (CC) and major complications and comorbidities (MCC) were assessed according to CMS.gov manual definitions.
RESULT(S): A total of 557 patients met inclusion criteria. Baseline demographics and surgical details: age 60.8 +/- 13.2, 67.5% female, BMI 28.3 +/- 6.67, 6.2% anterior approach, 81.0% posterior approach, 12.8% combined approach, 10.4 +/- 3.9 levels fused, op time 423.5 +/- 166.4 minutes, EBL 2061.4 +/- 1631.5 cc, LOS 7.6 +/- 5.4 days. 11 MetS patients were included. There was no significant difference in BL SVA (54.2degree vs 70.3degree), PT (26.7degree vs 23.7degree), PI-LL (16.4degree vs 21.2degree), or levels fused between groups (10.5 vs 10.6) (all p>0.05). Twenty-seven percent of MetS patients experienced a CC or MCC, with 18% undergoing revisions within 90 days (vs 13.2% and 3.2% for non-MetS, p<0.05). The average costs of surgery for MetS patients was $68,004.06 vs $48,726.40 for non-MetS patients (p<0.05).
CONCLUSION(S): Metabolic syndrome is a growing concern among health care providers. In metabolic syndrome patients undergoing corrective adult spinal deformity surgery, the total costs of surgery was 28.4% higher for metabolic syndrome patients ($68,004.06 vs $48,726.40). Optimizing modifiable factors like diabetes or BMI in preoperative patients may have an impact on cost effectiveness. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Miller et al. adult spinal deformity frailty index (ASD-FI) correlates with increased complication risk after surgery; however, its development is rooted in health related quality of life metrics (HRQLs) that may be subjective, and the 40 factors needed for its calculation limit the index's utility in a clinical setting. PURPOSE: Develop a simplified, modified frailty index for ASD patients STUDY DESIGN/SETTING: Retrospective cohort study PATIENT SAMPLE: A total of 531 ASD patients OUTCOME MEASURES: HRQLs, length of stay (LOS) METHODS: ASD patients (scoliosis>=20degree, SVA>=5cm, PT>=25degree, or TK >=60degree) with baseline (BL) and 2-year HRQL follow up. HRQL components were removed from the FI and top contributors to the ASD-FI score of the remaining were assessed via Pearson correlation, and included in forward multiple stepwise regressions. Factors with the largest R2 value were including in the modified, ASD-FI (clin-ASD-FI). Factors included in the clin-ASD-FI were regressed against mortality, extended length of hospital stay (>8 days), revisions, major complications and weights for the clin-ASD-FI were calculated via Beta/Sullivan. Total clin-ASD-FI score was created with a score from 0 to 1. Linear regression correlated the clin-ASD-FI with ASD-FI scores and published cut-offs for the ASD-FI were used to create the new frailty cutoffs: not frail (NF: < 0.11), frail (F: 0.11-0.21) and severely frail (SF: >0.21). Binary logistic regression assessed odds of complication or reop for frail patients. Logistic regressions were run to determine whether the clin-ASD-FI is superior to previously utilized measures predicting risk (age, ASA, previous FI, and CCI) for complications and reop.
RESULT(S): A total of 531 ASD patients (59.5yrs, 79.5%F). The final stepwise regression model R2 of 0.681: <18.5 or >20 BMI (weight: 0.0625 out of 1), cardiac disease (0.125), disability employment status (0.3125), diabetes mellitus (0.0625), hypertension (0.0625), osteoporosis (0.125), blood clot (0.1875), and bowel incontinence (0.0625). These factors calculated the score from 0 to 1, with a mean cohort score of 0.13+/-0.14. Breakdown by clin-ASD-FI score: 51.8% NF, 28.1% F, 20.2% SF. Increasing frailty severity was associated with longer LOS (NF: 7.0, F: 8.3, SF: 9.2 days; p<0.001). When assessing BL HRQL status between the new clin-ASD-FI groups, ODI, EQ5D, SRS, PCS, MCS, NRS-Back, and NRS-Neck were worse with increasing categorical frailty (all p<0.001). Frailty independently predicted occurrence of any complication (9.357[2.20-39.76], p=0.002) and reop (2.79[0.662-11.72], p=0.162). Specific complications predicted included infection, neurologic, operative, radiographic, and wound complications (OR: 1.69-5, all p<0.001). Chi-square and p-values for the historical risk predictors of complications are as follows: Age(complication: 1.01[1-1.03] p=0.052; reop: 0.999[0.984-1.01] p=0.866), ASA(complication: 1.102[1.20-2.18], p=0.002; reop: 1.31[0.927-1.84], p=0.177), previous frailty index(complication: 8.57[1.66-44.17], p=0.010; reop=2.629[0.498-16.06], p=0.241), CCI(complication: 1.24[1.10-1.40], p<0.001; reop: 1.06[0.943-1.20], p=0.320).
CONCLUSION(S): Utilizing an existing ASD frailty index, we proposed a modified version eliminating the patient-reported components. This index is a true assessment of physiologic status, and represents a superior risk factor to other risk assessment tools for baseline and revision spinal deformity surgery as a result of its immutability with surgery, lack of subjectivity, and ease of use. Future studies should explore external validation of the proposed frailty index. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The impact of neuromuscular disorders such as multiple sclerosis (MS) on outcomes following anterior cervical discectomy and fusion (ACDF) is underreported. PURPOSE: Identify the impact of MS on two-year (2Y) postoperative complications and revisions following 2-3-level ACDF for cervical radiculopathy (CR) or myelopathy (CM). STUDY DESIGN/SETTING: Retrospective review of the New York State Statewide Planning and Research Cooperative System (SPARCS) database. PATIENT SAMPLE: Patients undergoing 2-3 level ACDF for CR/CM. OUTCOME MEASURES: Two-year postoperative complications and reoperations.
METHOD(S): Patients undergoing 2-3 level ACDF for CR/CM were identified from SPARCS. Patients with a baseline diagnosis of MS were also identified. Patients with infectious/traumatic/neoplastic were excluded. The remaining patients were 1:1 propensity score-matched (MS to no-MS) for age, sex, race, Deyo index and compared for rates of 2Y postoperative complications and reoperations. Logistic regression models were utilized to determine significant predictors of these outcomes.
RESULT(S): A total of 302 total patients were identified (MS, n=151; non-MS, n=151). MS patients were more frequently female (72.8% vs 27.2%, p<0.001). Age was comparable (50.1 vs 50.1 years, p=0.225). MS patients incurred higher charges for their surgical visit ($41,029 vs $31,654) and higher LOS (2.8 vs 2.2 days), both p<=0.016. They experienced higher rates of deep vein thrombosis (DVT) (3.3% vs 0%, p=0.02), with similar overall medical (19.2% vs 21.2%), surgical (7.9% vs 10.6%), and total complications (21.9% vs 25.8%), all p>0.05. MS patients had similar rates of 2Y revisions (6.6% vs 5.3%, p=0.627). MS was not associated with medical, surgical, or overall complications or revisions at minimum 2Y follow-up.
CONCLUSION(S): Despite differences in demographics and higher rates of postoperative DVT, MS patients experienced comparable postoperative course with respect to other individual and overall complications and revisions following 2-3-level CF for degenerative spinal pathologies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Chiari malformations (CM) are congenital or acquired hind brain anomalies with resultant cerebellar tonsillar herniation through the foramen magnum. Chiari I malformation consists of herniation of the cerebellar tonsils into the foramen magnum thus crowding the craniocervcial junction. Surgical management is variable among these type 1 patients(pts) based on their presenting symptoms. PURPOSE: Identify complication rates following CM surgery. STUDY DESIGN/SETTING: Retrospective cohort study of (Kids' Inpatient Database) KID. PATIENT SAMPLE: Chiari Malformation Type I. OUTCOME MEASURES: Complication rates, fusion, decompression, duroplasty, laminectomy, LOS, Readmission.
METHOD(S): The KID database was queried for diagnoses of operative Chiari Malformation from 2003-2012 by ICD-9 codes (348.4). Differences in preoperative demographics (age/BMI) and perioperative complication rates between patient cohorts were assessed using Pearson's chi-squared tests and T-tests when necessary. Binary logistic regression were utilized to find significant factors associated with complication rate. Decision tree analysis was utilized for continuous variables predictive of complication rate. Certain surgical procedures were analyzed for their relationship with post-operative outcomes.
RESULT(S): A total of 13,812 CM-1 patients were isolated (10.12 yrs, 0.62 CCI). Of these pts, 8.2% (1,128) received a complication. From 2003 to 2012, the rate of complications for CM-1 pts decreased significantly (9.6%-5.1%) along with surgical rate (33.3%-28.6%), despite the increase in CM diagnosis (36.3%-42.3%; all p<0.05). CM-1 pts who had a complication were younger (9.73+/-6.8 yrs vs 10.2+/-6.3 yrs) and had a lower invasiveness score (0.35+/-1.0 vs 0.41+/-1.0), however; they had a larger CCI (1.10+/-1.6 vs 0.6+/-1.3) than those who did not have a complication (all p<0.05). The most prevalent comorbidities for these pts were cerebrovascular (16.67%), malignancy (11.6%), pulmonary (9.6%), and renal (7.1%; all p<0.05). CM-1 pts who experienced complications had a concurrent diagnosis of syringomyelia (7.1%) and also Scoliosis (3.2%; all p<0.05). CM-1 pts who did not have a complication had a greater surgical rate than those that had a complication (76.4% vs 23.6% p<0.05). Having an interbody instrument, having an invasiveness score>4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p<0.05). The most common complication was nervous system related (2.8%), anemia (2.4%), and acute respiratory distress (2.1%). CM-1 pts that underwent a fusion (3.4% vs 2.1%) had greater complication rates as well as those that underwent a craniotomy (23.2% vs 19.1%; all p<0.05). However, CM-1 pts who underwent a decompression had lower postop complications (21.3% vs 28.9%; all p<0.05). A total of 13,812 CM-1 patients isolated (10.12 yrs, 0.62 CCI). Of these pts, 8.2% (1,128) received a complication. From 2003 to 2012, the rate of complications for CM-1 pts decreased significantly (9.6%-5.1%) along with surgical rate (33.3%-28.6%), despite the increase in CM diagnosis (36.3%-42.3%; all p<0.05). CM-1 pts who had a complication were younger (9.73+/-6.8yrs vs 10.2+/-6.3yrs) and had a lower invasiveness score (0.35+/-1.0 vs 0.41+/-1.0), however; they had a larger CCI (1.10+/-1.6 vs 0.6+/-1.3) than those who did not have a complication (all p<0.05). The most prevalent comorbidities for these pts were cerebrovascular (16.67%), malignancy (11.6%), pulmonary (9.6%), and renal (7.1%; all p<0.05). CM-1 pts who experienced complications had a concurrent diagnosis of syringomyelia (7.1%) and also Scoliosis (3.2%; all p<0.05). CM-1 pts who did not have a complication had a greater surgical rate than those that had a complication (76.4% vs 23.6% p<0.05). Having an interbody instrument, having an invasiveness score>4.25 and receiving a fusion greater than 4 levels were all significant factors associated with receiving a complication postoperatively (p<0.05). The most common complication was nervous system related (2.8%), anemia (2.4%), and acute respiratory distress (2.1%). CM-1 pts that underwent a fusion (3.4% vs 2.1%) had greater complication rates as well as those that underwent a craniotomy (23.2% vs 19.1%; all p<0.05). However, CM-1 pts that underwent a decompression had lower postop complications (21.3% vs 28.9%; all p<0.05).
CONCLUSION(S): Treatment of Chiari malformation has been identified to have improved from 2003 to 2012 with increased identification of diagnosis and decreased complications. Chiari patients undergoing fusions and craniotomies are at a greater risk of postoperative complications especially when the instrumented fusions are performed on >4 levels. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Navigation assisted and robotics systems are becoming more widespread in their utilization and can be invaluable intraoperative adjuncts during spine surgery. These systems are utilized in hopes of improving surgical accuracy and clinical outcomes. However, there is a lack in specificity of which type of procedures benefit the most from use of navigation versus robotics. PURPOSE: Identify Trends of Navigation and Robotic assisted elective spine surgeries from the onset of inception. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Elective spine patients from (2007-2016). OUTCOME MEASURES: Complications, procedures, levels fused.
METHOD(S): Patients(pts) between 2007-2016 in Nationwide Inpatient Sample (NIS) were isolated by ICD9 codes for Navigation [Nav] or Robotic [Rob]-Assisted surgery. Basic demographics and surgical variables were identified between each group via chi-squared and t-tests. Each system was analyzed from 2009-2015 for trends in usage with specific procedures and specific diagnoses.
RESULT(S): Included 3,759,751 elective spine patients (56.9 yrs, 52.7% F) with 100,488 Nav and 4,724 Rob pts. Nav pts were younger (56.7 vs 62.7) and had a lower comorbidity index (1.8 vs 6.2; all p<0.05). Nav pts also had more decompressions (65% vs 42%), fusions (71% vs 50.5%), anterior (17% vs 16.7%), posterior (58.3% vs 36.8%), and combined approach (7.1%vs 5%) than Rob pts. Overall, complication rates increased for Nav (5.8%-21.7%) and Rob pts (3.3%-18.4%) as well as for 2-3 level fusions (50.4%-52.5%) and (1.3%-3.2%); respectively. Concomitantly, Rob and Nav systems have been used on increasingly invasive spinal procedures (Rob:1.7-2.2; Nav: 3.7-4.6). During this time, the rate of posterior approaches (27.4%-41.3%) increased as well as osteotomies (4%-7%) and spinal fusions (40.9%-54.2%) for Rob pts. However, the rates for anterior approach for Rob procedures has since decreased (14.9%-14.4%). Nav increased for posterior (51.5%-63.9%) and anterior approaches (16.4%-19.2%) despite the decrease rate of osteotomies (2.1%-2.1%) and decompressions (73.6%-63.2%).
CONCLUSION(S): From 2007 to 2016 Robotic and Nav systems have been performed on increasing invasive spine procedures. Robotic systems have shifted from anterior to posterior approaches especially for spinal fusions. While, Navigation computer-assisted procedures have been increasingly used for different approaches, but have decreased in rates of usage for decompression procedures. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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