Faculty Bibliography

BACKGROUND CONTEXT: There have been few investigations into national trends in the use or outcomes of patients treated with robotic assisted surgery. PURPOSE: To evaluate if incorporation of robotic assisted procedures will lead to a rise in suboptimal outcomes. STUDY DESIGN/SETTING: Retrospective review of a national patient database between 2010-2016. PATIENT SAMPLE: A total of 4,109 weighted hospital discharges. OUTCOME MEASURES: Length of stay, complications, invasiveness.
METHOD(S): Inclusion criteria: elective spine surgery procedures as defined by ICD-9-CM and ICD-10-CM codes. Descriptive statistics assessed demographic information for the cohort. Rates of open and MIS robot assisted procedures were assessed, as well as trends in postoperative complications, and length of stay. Propensity score matching was performed between robotic spine surgery patients and non-robotic spine surgery patients for levels fused. Regression analysis was used to assess robot assisted procedures as a predictor of complications and extended LOS (LOS above 75th percentile), unfavorable discharge, and death during hospitalization.
RESULT(S): A total of 4,109 discharges were included. The overall trends in robotic surgery show a significant increase from 2010 to 2016, increasing from 11 recorded cases to 1,535 in 2016 (p<0.001). The majority of cases were open, however, an increasing percentage of cases have been MIS (8% in 2010 vs 12% in 2016, p<0.001). Average length of stay has significantly decreased from 9.5 days in 2010 to 4.4 days in 2016 (p<0.001). Postoperative hardware complications have significantly decreased from a high of 15.6% of cases in 2011 to 0.3% of cases in 2016, as well as DVTs (9.4% in 2011 vs 0% in 2016, both p<0.001). However, overall complication rates have increased, from 25% in 2011 to 29.3% in 2016 (p<0.001). In an analysis of invasiveness matched non-robot assisted patients, robot assisted surgery was not predictive of extended LOS, unfavorable discharge, total post-operative complications, or death during hospitalization (all p>0.05). Robot assisted surgery was predictive of bleeding complications (hemorrhage and hematoma) compared to non-robot surgery patients (OR: 2.05 [1.10-3.82], p=0.02).
CONCLUSION(S): Robot assisted surgery is an increasing implemented technique in spine surgery, with a significant rise from 2010 to 2016. However, during that period there has been a concurrent rise in postoperative complications. Invasiveness matched robot assisted patients were at significantly higher odds of bleeding complications compared to non-robotic patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Prior literature has demonstrated that correction of sagittal plane deformity in adult patients has resulted in improvements in health-related quality of life (HRQOL) outcomes. In the absence of sagittal plane pathology, the effects of coronal malalignment under-correction in patients with spinal deformity have not been fully investigated. PURPOSE: To evaluate the impact of coronal malalignment correction on HRQOL outcomes in adult spinal deformity. STUDY DESIGN/SETTING: Retrospective review of a multicenter database. PATIENT SAMPLE: A total of 522 ASD patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients without severe sagittal deformities. OUTCOME MEASURES: Our outcome measures included Oswestry Disability Index (ODI), SF-36 Physical Component Summary (PCS), and several other SF-36 and SRS-22r health domains scores.
METHOD(S): Using a prospective, multicenter database, we identified 1560 surgical patients. Of these, 522 patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients who only had coronal plane deformity. We only included patients undergoing primary surgery. We then compared 2-year post HRQOL outcomes in patients that had their coronal malalignment corrected (CVA < 40mm) vs not.
RESULT(S): Mean age of patients was 54 +/- 15 years, 91% females. 79 patients were identified with only a coronal plane deformity undergoing a primary ASD surgery. Of these, 38 (48%) were under-corrected and 41 (52%) had their coronal alignment corrected to <40mm. Compared to the corrected group, the uncorrected group had a higher ODI (26.0+/- 2.9 vs 14.7+/- 2.5; p=0.002) and lower SRS-22r Activity (3.6+/- 0.14 vs 4.2+/- 0.11; p=002), SRS-22r Appearance (3.3+/- 0.16 vs 3.9+/- 0.12, p=.001), SRS-22r total (3.6+/- 0.12 vs 4.1+/- 0.11, p=.004), SF-36 Physical Component Summary (40.8+/- 1.3 vs 46.8+/- 1.6; p=.005), SF-36 Physical Function (40.5+/- 1.7 vs 46.0+/- 1.5, p=.01), SF-36 Bodily Pain (41.7+/- 1.6 vs 47.8+/- 1.5, p=.006), SF-36 General Health (47.2+/- 1.8 vs 52.2+/- 1.4, p=.03), SF-36 Social Functioning (45.9+/- 2.1 vs 51.7+/- 1.4, p=.03), SF-36 Mental Health (48.9+/- 1.9 vs 54.2+/- 1.8, p=.048) 2 years following index surgery.
CONCLUSION(S): Patients with coronal malalignment and little sagittal plane deformity experience worse improvement in pain and disability, with under-correction of their coronal plane deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The literature reports age and frailty as strong predictors of outcomes following spine surgery. This postop impact calls for investigation of unique adjustment parameters accounting for the two factors. Grasping the concordance of surgical factors with age and frailty may help surgical planning for individualized, optimal postop outcomes. PURPOSE: Modify the age-adjusted alignment goals with frailty to optimize outcomes in surgical adult spinal deformity (ASD) patients. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter spine database PATIENT SAMPLE: A total of 853 patients OUTCOME MEASURES: Age-frailty-adjusted alignment goals (AF); optimal outcomes METHODS: Included: ASD patients with baseline (BL) frailty and ODI scores, radiographic parameters (PT, SVA, PILL, TPA). Patients were dichotomized by the ASD frailty index (not frail, frail). Linear regression analysis established normative radiographic thresholds, utilizing previously published age(A) specific (<35, 35-55, 45-54, 55-64, 65-74, >=75y/o) US-Normative ODI values converted from SF-36 PCS, in conjunction with frailty score. Patients met AF goals if 1-year postop alignment was within one standard deviation (+1SD Overcorrected [Over]; -1SD Undercorrected [Under]).
RESULT(S): A total of 853 patients were included (57.4+/-15yrs, 80%female, 27.2+/-5.9kg/m2). BL frailty: 438 not frail (51.3%), 308 frail (46.8%). Primary analyses demonstrated correlation between BL frailty score, PT, PILL, TPA, SVA, ODI (P<0.001). Linear regression analysis (R: 0.420-0.517,p<0.001) developed AF specific alignment threshold equations: (PT=5.7+0.25[A]+0.86[F]+0.073[ODI]), (SVA=-63.85 +1.23[A]+93.48[F]+0.52[ODI]), (PI-LL=-21.35+0.83[A]+22.89[F]+ 0.083[ODI]), (TPA=-2.91+0.30[A]+10.12[F]+ 0.097[ODI]). Thresholds increased with age and frailty for all four parameters. Patients<35 years and not frail predicted PT:13.3degree, SVA: -13.3mm, PI-LL: -6.6degree, TPA: 7.5degree, while patients>=75 and frail increased in all thresholds (PT: 29.1degree, SVA: 96.9mm, PI-LL: 25.6degree, TPA: 29.6degree). 38.1% patients matched PT ABF, 43.8% SVA, 38.6% PI-LL, and 45.3% TPA. Match PT patients had less PJK incidence 3mos-2yrs (Match:51% vs O/U:55.9%; p=0.173), as well as SVA (Match: 45.5% vs O/U: 60.8%; p<0.001), PI-LL (Match: 42.9% vs O/U: 61%; p<0.01), and TPA (Match: 49.5% vs O/U: 57.8%; p=0.015). PT Match group met MCID for SRS-22 Pain more (p=0.005), while SVA, PILL and TPA Match met MCID for ODI, PCS, and SRS-22 more (p<0.05). Match SVA and TPA had less overall LOS(p<0.01).
CONCLUSION(S): Incorporating frailty with age-specific goals influenced SVA, PT, PILL and TPA. Use of these modified goals is more sensitive to response to surgery than age and contribute to superior clinical and complication outcomes. Specific alignment thresholds accounting for age and frailty appeal for less rigorous alignment goals in older and severely frail patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Thoracolumbar malalignment is often seen in patients presenting with cervical deformities. For operative cervical deformity (CD) patients, it is unknown whether certain thoracolumbar parameters play a large role in poor outcomes (complications, distal junctional kyphosis, reoperation) and whether addressment of such parameters is warranted. PURPOSE: To investigate the impact of cervical to thoracolumbar ratios on poor outcomes in CD corrective surgery. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: 110 CD patients. OUTCOME MEASURES: Radiographic parameters: regionally and globally; complications; distal junctional kyphosis (DJK); reoperations; health-related quality-of-life (HRQLs): NDI, EQ5D, mJOA.
METHOD(S): Included: surgical CD pts (C2-C7 Cobb >10degree, CL>10degree, cSVA >4cm, or CBVA >25degree) with full baseline and 1-year data. Patients were assessed for ratios of preop cervical and global parameters including: C2 slope/T1 slope, TS-CL/PI-LL, cSVA/SVA. Deformity classification ratios of cervical (Ames-ISSG) to spinopelvic (SRS-Schwab) were investigated: cSVA modifier/SVA modifier, TS-CL modifier/PI-LL modifier. Cervical to thoracic ratios included C2-C7 lordosis/T4-T12 kyphosis. Correlations assessed the relationship between ratios and poor outcome (major complication, reoperation, HRQL decline or failure to meet MCID). Decision tree analysis through multiple iterations of multivariate regressions assessed cut-offs for ratios for acquiring suboptimal outcomes.
RESULT(S): A total of 110 cervical deformity patients were included in the present analysis (61.5+/-9.9 years, 66% female, 28.8+/-7.5 kg/m2). By approach, 18.2% underwent anterior-only procedures, 46.4% posterior, and 35.4% combined. Average levels fused: 7.7+/-3.7 levels (anterior: 3.5, posterior: 8.5). The average preoperative radiographic ratios assessed included a C2 slope/T1 slope 1.56, TS-CL/PI-LL of 11.1, cSVA/SVA of 5.4, CL/TK of 0.26. Ames-ISSG and SRS-Schwab modifier ratios of cSVA/SVA 0.1 and TS-CL/PI-LL of 0.35. Pearson correlations demonstrated a significant relationship between major complications and the baseline TS-CL/PI-LL with a cutoff of >12.72 (p=0.034), >0.482 Ames TS-CL/Schwab PI-LL modifiers (p=0.019), and the CL/TK ratios (>0.814, p=0.050). Reoperation had a significant correlation with the TS-CL/PI-LL (>5.819, p=0.009) and the cSVA/SVA (>3.79, p=0.002) ratios. Postoperative DJK had a correlation with the C2 slope/T1 slope (>1.59, p=0.017) and CL/TK (>0.692, p=0.0629) ratios. Not meeting MCID for NDI correlated with the CL/TK ratio (>1.402, p=0.016) and not meeting MCID for EQ5D correlated with the Ames TS-CL/Schwab PI-LL (>0.564, p=0.010).
CONCLUSION(S): Consideration of the ratio of distal regional to global alignment is a critical determinant of outcomes in cervical deformity corrective surgery. Several key ratios of cervical to global alignment were found to correlate with the occurrence of suboptimal realignment parameters, or poor clinical outcomes. A larger cervical lordosis to thoracic kyphosis was most representative of this risk, which predicted a complication, DJK, and not meeting MCID for NDI. 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: Due to the complexity and invasiveness of deformity correction, poor outcomes are often associated. Currently, it is unknown what factors predict an outcome which operation may not be warranted (reoperation, major complications, clinical deterioration). PURPOSE: To investigate what patient factors justify determining a patient ineligible for a deformity correction. STUDY DESIGN/SETTING: Retrospective review of a prospective, consecutively enrolled adult spinal deformity (ASD) database. PATIENT SAMPLE: Operative patients with complete 2-year HRQL and radiographic data were included. OUTCOME MEASURES: HRQLs: Oswestry Disability Index (ODI), complications; reoperations.
METHOD(S): Patients >18yrs undergoing surgery for ASD (scoliosis >=20degree, SVA >=5cm, PT >=25degree, or TK >=60degree). An unsatisfactory outcome was defined by the following categories met at 2Y: (1) clinical: deteriorating in ODI at 2Y follow-up (2) complications/reop: having a reoperation and major complication were deemed unacceptable for surgery (NoOp). Baseline demographic, clinical and radiographic information were utilized through univariate/multivariate analyses to assess predictive factors of NoOp patients in adult spinal deformity patients. Multivariate regression with backward model selection was employed to create a model for when not to operate.
RESULT(S): A total of 633 ASD patients (59.9 years, 79% F, 27.7 kg/m2, CCI: 1.74) were included. By approach, 0.6% were anterior, 69.7% posterior and 29.5% combined approaches, with a total number of levels fused as 7.5+/-2.1. Baseline severe Schwab modifier incidence (++): 39.2% PI-LL, 28.8% SVA, 28.9% PT. 15.5% of patients deteriorated in ODI by 2 years, while 7.6% underwent a reoperation and had a major complication. This categorized 11 (1.7%) of patients in the total cohort as NoOp. NoOp patients had were more comorbid in terms of arthritis (73%) heart disease (36%) and kidney disease (18%), p<0.001. Surgically, NoOp patients had an overall greater EBL (4431ccs), underwent more osteotomies (91%), specifically Ponte (36%) and Three Column Osteotomies (55%), which occurred more at L2(91%). NoOp patients underwent more PLIFs (45%) and had more blood transfusion units (2641ccs), all p<0.050. The multivariate regression predicting the NoOp ASD group determined a combination of a baseline DRAM score in the 75th percentile, having arthritis and kidney disease, a baseline right lower extremity motor score <=3, cSVA >65mm, C2 slope >30.2degree, CTPA >5.5degree for an R2 value of 0.535 (p<0.001).
CONCLUSION(S): When addressing adult spine deformities, a negative outcome of clinical deterioration, major complications, and reoperations are exceedingly rare, but do occur. This tends to occur in severely comorbid patients with major baseline psychological distress scores, severe neurologic dysfunction and concomitant cervical malalignment not addressed at surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Substantial adult spinal deformity (ASD) research has focused on sagittal plane radiological assessment and emphasized the importance of sagittal correction on patient-reported outcomes. It seems less attention has been given to evaluation of ASD in the coronal plane. However, recent ASD studies have demonstrated baseline global coronal malalignment (GCM; substantial displacement of the C7 coronal plumb line from midsacrum) in up to 35% of patients. Moreover, GCM can worsen postoperatively or may occur as an iatrogenic complication in previously balanced patients. Collectively, this may suggest that the associated clinical impact of GCM on ASD surgical outcomes has been underestimated. Currently, few reports focus on surgical outcomes in ASD patients with GCM. PURPOSE: Our objective was to assess treatment outcomes and complication rates associated with ASD surgery in the subset of patients with severe GCM. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry. PATIENT SAMPLE: Enrollment required: age >=18 years, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: Radiographic correction (both standard coronal and sagittal spinopelvic deformity measurements) and health-related quality of life (HRQL) outcomes, which included Oswestry Disability Index (ODI), Short Form-36 (SF-36) scores, Scoliosis Research Society-22 (SRS-22) scores, and back/leg pain numerical rating scale (NRS) scores.
METHOD(S): Surgically treated ASD patients with severe GCM (coronal C7PL-midsacral offset magnitude >=1 SD above the mean) were identified. Baseline and follow-up radiographic and HRQL outcomes were analyzed. Percentages of patients achieving minimal clinically important difference (MCID) and substantial clinical benefit (SCB) were assessed. Demographic, frailty, surgical, and complications data were collected. The primary focus for analysis was on patients who reached minimum 2-year follow-up.
RESULT(S): Of 691 potentially eligible operative patients (mean GCM = 4+/-3 cm), 80 met criteria for severe GCM >= 7cm. Of these 80 patients, 62 (78%, mean age 64 years, 81% women) had minimum 2-year follow-up. Baseline frailty score was 3.9+/-1.5 (indicating patients were frail) and 48% had prior spine fusion. Surgical data included: posterior-only (58%), mean fusion 13 levels, sacroiliac fixation (97%), and three-column osteotomy (36%). Postoperative biplane alignment improved significantly (p<0.001): GCM 11 to 4 cm, lumbar Cobb 30degree to 11degree, C7-S1 SVA 13 to 4 cm, and PI-LL 31degree to 5degree. Overall HRQL improved significantly (p<=0.003): ODI 51 to 37, SF-36 PCS 29 to 37, SRS-22r 2.6 to 3.5, and back/leg pain NRS 7 to 4 and 5 to 3, respectively. Thresholds for MCID/SCB were met in 43-83% of patients. A total of 89 complications were reported (34 minor/55 major), and 45 (73%) patients had >=1 complication (most commonly rod fracture [19%] and PJK [18%]). There were 34 reoperations in 22 (36%) patients (most common indications rod fracture/PJK). The 18 patients who did not achieve 2-year follow-up had a mean of 0.63 years follow-up, and the types of complications encountered in these 18 patients were comparable to those encountered in patients with 2-year follow-up.
CONCLUSION(S): ASD surgery for patients with severe GCM is associated with significant improvements in biplane alignment and HRQL outcome measures despite high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: As the field of corrective cervical deformity (CD) surgery progresses, surgeons continue to take on more challenging cases. In order to minimize suboptimal postoperative outcomes it is important to develop a tool that allows for proper preoperative risk stratification. PURPOSE: Develop individualized predictive models for identification of risk-factors that lead to the development of major complications, revisions, and unplanned reoperation. STUDY DESIGN/SETTING: Retrospective cohort study of a prospective adult cervical deformity database. PATIENT SAMPLE: A total of 105 CD patients. OUTCOME MEASURES: Major complications (prolonged hospitalization, invasive intervention, prolonged or permanent morbidity, death within 1 year[1Y]), unplanned revision or reoperation after CD surgery within 1Y, HRQOL (NDI, mJOA, EQ5D).
METHOD(S): CD patients (cervical kyphosis >10degree, coronal scoliosis >10degree, cSVA >4cm, TS-CL >10degree, or CBVA >25degree) >=18 years old with complete baseline (BL), 1Y HRQoL and radiographic data. Patients were stratified into two groups based on their outcome from surgery: revision (Rev) and major complication (MC). Descriptive analysis identified cohort demographics, radiographic parameters and surgical details. Univariate analysis of preoperative and surgical factors was conducted to determine associations with any of the two outcomes. Stepwise logistic regressions identified surgical, radiographic, and HRQL factors that were associated with Rev or MC. Decision tree analysis established cut-offs for predictive variables.
RESULT(S): A total of 105 CD patients were included (61.6yrs, 67%F, BMI: 28.4kg/m2, CCI: 0.96+/-1.3). Surgical details: 7.6+/- 3.7 levels fused; mean EBL of 816 mL. By surgical approach, 45.71% had a posterior approach, 35.24% combined approach, and 19.05% anterior approach. Radiographically at baseline, patients presented with: PT: 18.9+/- 11.3; PI: 53.0+/-11.2; PI-LL: -0.45+/-17.2; SVA: -4.3+/-66.8, TS-CL: 37.9 +/-20.2; cSVA: 38.4+/-19.9. Postoperatively, 20 patients experienced a MC and 17 patients underwent a subsequent rev. instrumentation location (LIV: 1.1[1.0-1.3] and UIV: 1.5[1.1-2.1]) was significantly associated with undergoing a rev after index surgery (all p<0.05). The development of a postoperative MC was significantly associated with BL radiographic pelvic parameters (all <0.05). Predictive modeling incorporating preoperative and surgical factors identified development of a Rev to include: UIV>C3, LIV>T3, C2-T3 SVA<46.7degree, C2-C7 SVA>57.6degree, CTPA>7.8degree, and C2S<60.4 (AUC:0.80). For developing a MC, a model consisting of preoperative and surgical factors included BL EQ5D-VAS<30, TS-CL>59.2degree, C2-C7 SVA > 69.1degree, C2-T3 SVA < 18.6, Apex C2-C7 SVA >4.25, surgical invasiveness and posterior osteotomies (AUC:0.83).
CONCLUSION(S): Major adverse events were not uncommon following adult cervical deformity correction. Risk stratification models were developed to predict with high accuracy the occurrence of these common significant postoperative events. Revisions were predicted with an accuracy of 80% using a predominance of radiographic variables, while the occurrence of other major complications was also predicted with high reliability utilizing additional baseline HRQoL data and surgical factors. 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: Operative treatment of adult spinal deformity (ASD) can be very challenging with high complication rates. Despite these challenges it's well established that pts benefit from such treatment. However, the surgical outcomes for pts with mild scoliosis and age appropriate sagittal alignment have not been reported. PURPOSE: To determine if patients (pts) with mild scoliosis and age appropriate sagittal alignment have favorable outcomes following surgical correction. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter ASD database. PATIENT SAMPLE: ASD patients: operative pts age>=18, and all preoperartive pelvic tilt (PT), mismatch between pelvic incidence and lumbar lordosis (PI-LL), and C7 sagittal vertical axis (SVA) within established age adjusted parameters with minimum 2-year follow up. A subanalysis for pts with max coronal cobb angle 10-30degree (mild scoli) was done. OUTCOME MEASURES: Health-related quality of life (HRQOL) scores: Oswestry Disability Index (ODI), Short form-36(SF36), Scoliosis Research Society (SRS22), back/leg pain numerical rating scale (NRS) and minimum clinically important difference (MCID)/substantial clinical benefit (SCB). Radiographic values: max coronal cobb angle, coronal C7 plumb line, PT, PI-LL, thoracic kyphosis (TK), SVA. Demographic, frailty, surgical and complications data were collected.
METHOD(S): Two-year and baseline HRQOL/radiographic data were compared.
RESULT(S): A total of 103 pts were included from 667 operative patients (89.3% female, avg age 59.8+/-13.1yrs). Of the 103 pts, 29 (28.2%) had max preop coronal cobb angle 10-30degree. Two-year max coronal cobb angle and C7 coronal plumb were significantly improved compared to baseline (p<0.001 for both the overall cohort and mild scoli). All 2yr HRQOL measures were significantly improved compared to baseline(p<0.001) for both groups. 33.3-81.5%% of mild scoli pts met either MCID/SCB for all HRQOL. In mild scoli pts, 62.1% had min one complication, 27.6% had a major complication with 24.1% requiring a revision.
CONCLUSION(S): Pts with mild scoliosis and sagittal alignment within age appropriate parameters benefit from surgical correction at 2 years postop both radiographically and clinically including 81.5% meeting MCID for SRS pain despite having high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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