Three-column osteotomies (3CO), in the form of pedicle subtraction or vertebral column resection, have become common in adult spinal deformity (ASD) in cases of severe deformity or iatrogenic ...sagittal malalignment. Although a powerful surgical intervention, 3COs can increase the risks associated with correction. The purpose of this study is to investigate whether more appropriate usage of 3CO is occurring over time.
To investigate the evolution of 3CO usage.
Retrospective cohort study of a prospective adult thoracolumbar deformity database.
This study included 762 ASD patients.
Complications, patient-reported outcome measures (ODI, SRS, SF-36).
Operative ASD patients (scoliosis >20º, SVA >5cm, PT >25º, or TK >60º) with available baseline and 2-year radiographic and HRQL data were included. Patients were stratified into 2 groups by DOS: Group I (2008-2013) and Group II (2013-2018). Patients who underwent a 3CO in Group I and Group II were then isolated for outcomes analysis. Severe sagittal deformity was defined by a SVA >9.5cm and “match” was defined by meeting ideal age-adjusted alignment. Best clinical outcome (BCO) was defined as ODI <15 and SRS >4.5 as per Smith et al. Univariate, bivariate (BVA) and multivariate analysis (MVA) was used to assess differences in surgical, radiographic, and clinical parameters.
A total of 762 ASD patients met inclusion criteria (59.9yrs±14.0, 79%F, BMI: 27.7 kg/m2 ±6.0, ASD-FI: 3.3±1.6, CCI: 1.8 ±1.7). Controlling for baseline SVA, mismatch, revision status, age, and CCI, Group II was less likely to have a 3CO (.6.4-.97 compared with Group I (21% vs 31%, both p<0.05). Controlling for age, CCI, and baseline deformity, patients who achieved a match in SVA or PI-LL in Group II showed a lower rate of 3CO (.510.27-.98, (p<0.05). In an isolated cohort of patients with severe sagittal deformity, controlling for age and CCI showed a lower likelihood of Group II receiving a 3CO (0.5.3-.94, p<0.05). The following analysis is based solely on patients who had a 3CO from each Group (79 patients in Group I and 59 patients in Group II). MVA controlling for age, deformity, CCI, and invasiveness showed Group II trended towards a higher usage of hooks, tethers, and cement prophylaxis (2.86-4.7, p=.11), a higher usage of supplemental rods 21.87.8- 61, (p=.001), and lower likelihood of PJF 0.23.07-.76, PJK by 3Y 0.23.1-.55, rod breakage 0.30.1-.9, and overall hardware complications 0.28.1-.8, (all p<0.05). Group II had a lower 2Y ODI and higher SF-36 Mental/Physical/Social/Emotional, SRS Activity/Mental/Pain and SRS-Total, p<0.05. Controlling for BL ODI, Group II was more likely to reach BCO ODI 2.81.2-6.4 and SRS 4.61.3-16, p<0.05.
Over a seven-year period, the rates of 3CO usage have declined, including in cases of severe deformity, with an increase in the usage of PJK prophylaxis. A better understanding of the utility of 3CO, along with a greater implementation of preventative measures, has led to a decrease in complications, PJF, PJK, and a significant improvement in patient reported outcome measures.
This abstract does not discuss or include any applicable devices or drugs.
Proximal junctional kyphosis (PJK) is a common cause of revision surgery for ASD patients. Surgeons may elect to perform a proximal extension of the fusion, or, also correct the source of the ...lumbo-pelvic mismatch. The goal was to determine if there is clinical benefit in addressing the root cause of PJK.
To investigate the clinical benefit of addressing malalignment in revision surgery for PJK.
Retrospective cohort study of a prospective multicenter ASD database.
A total of 137 ASD patients.
Complications, HRQLs (SF-36, ODI, SRS-22).
ASD patients undergoing revision surgery for PJK with fusion to ilium and an upper instrumented vertebrae at C5 or below. Correction in sagittal alignment was identified by patients who went from under- or overcorrected prerevision in PI-LL, SVA or PT to an ideal matched alignment in the Schwab age-adjusted criteria. Improvement in PI-LL was defined by a decrease in SRS-Schwab deformity category.
A total of 137 ASD patients undergoing revision surgery for PJK. 12.6% (19) were anterior and 84% (127) were posterior approaches. Operative time was 309±137, EBL 1327±1519, 75% had osteotomies and 33% had 3-column osteotomies. Average number of levels fused was 11±5. A total of 46% of patients undergoing revision surgery for PJK were corrected in sagittal alignment as well. Specifically, 21% of patient were corrected in PT, 20% corrected in SVA, and 14% corrected in PILL. Patients corrected in SVA vs fusion extension only had similar rates of PJK by 2 years, with a lower ODI (p<0.05) and higher SRS-Total/component and SF-36 components scores (p>0.05). Patients under corrected in SVA initially and overcorrected post-operatively had a greater development of recurrent PJK (86% vs 63%, p=.066). Patients undercorrected in PILL preoperatively and overcorrected postoperatively had a greater development of recurrent PJK (70% vs 56%, p=.184). Patients who were under/overcorrected in PILL and matched postoperatively, due to surgical realignment at revision, trended towards a lower NSR 2Y back pain (2.4 vs 3.9, p=.20). In a cohort of patients with 2Y follow-up (n=52), patients who improved in PI-LL had lower rates of PJF (8% vs 17%, p=.4) and reoperation (21% vs 32%, p= .4) than patients who only had an extension of fusion. Patient who were under/overcorrected and matched in T1PA showed lower rates of post-operative PJK (44% vs 55%, p=.6), 2Y PJK (67% vs 74%, p=.6) and proximal junctional failure (11% vs 15%, p=.7).
In patients undergoing revision surgery for PJK, those who maintained poor sagittal alignment showed worse clinical outcomes compared with patients who had their abnormal lumbo-pelvic mismatch corrected as well. While limited by sample size, these findings suggest addressing the root cause of surgical failure in addition to proximal extension of the fusion may be beneficial. Future studies with a larger cohort should be done to further investigate.
This abstract does not discuss or include any applicable devices or drugs.
A previous study by Pellisé et al identified that a lowest instrumented vertebrae (LIV) at the pelvis, frailty, and sagittal deformity (global sagittal alignment SVA, lordosis gap PI-LL, T1 sagittal ...tilt T1Slope) were strong preoperative predictors of major complications. In addition to the preoperative predictors, blood loss and surgical time were strong predictors that occur operatively. It is unknown whether being at risk by these criteria has an effect on cost of surgery.
To determine whether previously established risk stratification criteria will reduce operative costs.
Retrospective cohort study of a prospectively collected multicenter ASD database.
This study included 952 ASD patients.
Health-related quality of life measures (HRQLs), quality adjusted life years (QALYs), utility gained, ODI, total cost.
Adult spinal deformity (ASD) patients with complete baseline (BL) and 2-year (2Y) HRQLs and radiographic data were included. Frailty score, sagittal deformity measures, blood loss, and surgical time were divided into tertiles, with the highest tertile being high risk. Published methods converted ODI to SF-6D. QALYs utilized a 3% discount rate for residual decline to life expectancy (LE, 78.7 years). Cost was calculated using the PearlDiver database and assessed for complications/major complications and comorbidities according to CMS.gov definitions. Cost per QALY at 2Y and LE were calculated for additive risk factors (LIV at pelvis, high frailty, any high sagittal deformity measure, high blood loss, high surgical time). These costs represented national averages of Medicare pay-scales for services within a 30-day window including length of stay and death differentiated by complication/comorbidity, revision, and surgical approach. Internal cost data were based on individual patient DRG codes.
Of 926 patients included, 118 did not meet any risk criteria, 171 met 1, 207 met 2, 151 met 3, 56 met 4, and 3 met 5 (these 3 patients were excluded due to small sample size). There was a significant trend (R2=0.897) in terms of national average cost at 2-years with increasing amount of risk measures met, as cost increased by $11,566 with each additional risk factor. Amount of risk factors met had a positive correlation to baseline ODI (0: 30.89; 1: 39.66; 2: 46.96; 3: 51.59; 4: 54.69; p<0.001) and 2Y ODI (0: 18.06; 1: 22.55; 2: 27.53; 3: 34.23; 4: 38.54; p<0.001). When analyzing initial surgical cost by DRG code, there was a $3,844 increase in cost per risk factor (R2=0.8703). Patients meeting 2 risk factors had the highest ODI improvement from BL to 2Y (p=0.06). QALYs gained at LE decreased by 0.0756 per risk factor (R2=0.8153). National average cost per QALY at 2Y increased by $45,852 per risk factor (R2=0.4151), and cost per QALY at LE increased by $15,759 per risk factor (R2=0.8822).
Increasing risk factors involving frailty, baseline deformity, and operative factors reduce cost effectiveness by increasing total cost and reducing QALYs. Preoperative or intraoperative measures to reduce a patient's amount of applicable risk factors would concurrently reduce operative cost and improve cost-effectiveness. Awareness of non-modifiable risk factors may also help educate surgical approach.
This abstract does not discuss or include any applicable devices or drugs.
Restoring sagittal alignment in adult spinal deformity (ASD) surgery is a common goal to improve patient clinical outcomes and minimize long-term complications. The global alignment proportionality ...score (GAP) has been validated to consistently predict outcomes, however, our goal is to determine which components of the GAP score have the greatest impact on clinical and HRQL outcomes, and whether certain components can be prioritized when determining postoperative alignment goals.
To investigate the impact of GAP components on patient outcomes.
Retrospective cohort study of prospective, multicenter ASD database.
A total of 674 ASD patients.
Complications; Health-related quality of life (HRQL): ODI, SF-36 GH, SRS-22r, NSR
Operative ASD patients (scoliosis >20, SVA>5cm, PT>25, or TK>60) with a fusion at L1 or higher and available baseline (BL) and 2-year (2Y) radiographic and HRQL data. Proportioned alignment in 4 parameters: PV (Pelvic Version- based on sacral slope), LL (Lumbar Lordosis), LDI (Lumbar Lordosis Index), and SP (Spinopelvic- based on global tilt: sum of the C7 vertical tilt and the pelvic tilt) was investigated. Linear regression analysis, controlling for the others determined how alignment correlated with HRQL outcomes (SRS, ODI, SF36, back and leg pain) and complications. Conditional inference tree (CIT) modeling was then used to rank components hierarchically to determine which components were most impactful.
There were 674 ASD patients who met inclusion criteria (59.9years±14.0, 79%F, BMI: 27.7 kg/m2 ±6.0, ASD-FI: 3.3±1.6, CCI: 1.8 ±1.7). Surgically, patients had mean levels fused of 11.1±4.4, LOS of 7.9 days±4.4, EBL of 1577 mL, operative time of 377 min, with 63% undergoing an osteotomy. In a component analysis, alignment in GAP SP was the only component that predicted meeting MCID for SRS and ODI, and was associated with a higher SRS-Activity, SRS-Satisfaction, and NSR Leg pain at 2Y. Ranked by CIT, proportioned alignment in GAP SP was most predictive of achieving a higher SRS-Total score, higher SRS-Appearance and lower ODI, followed by GAP LDI and GAP LL. GAP LL proportionality predicted a higher SF-36 General Health Score and lower likelihood of mechanical failure .4.24-.8. Patients aligned in GAP SP were less likely to develop PJK by 2Y 0.42.26-.7 and PJF .27.1-.7, (all p<0.05). With a malalignment in GAP SP, being proportioned in GAP LL was correlated with a lower risk of PJK at 2Y .47.27-.780 (GAP LDI trended .65.4-1.04, p=.074). With malalignment in GAP LDI, being proportioned in GAP SP was correlated with increased incidence of` PJK 21.02-4, while GAP LL lowered incidence .5.3-.9, p<0.05.
Although GAP has been validated to predict mechanical complications, in cases of older, severely deformed, severely frail or revision cases there was no association. The spino-pelvic component of the GAP score, based on global tilt, provides an accurate overall picture of spinal and pelvic alignment and is therefore the most powerful predictor of ODI, all SRS, leg pain and development of PJK/PJF. GAP lumbar lordosis aligned patients had a higher SF-36 General health score and were less likely to develop mechanical failure.
This abstract does not discuss or include any applicable devices or drugs.
As surgical methods and technology advance, so should improvements in patient outcomes and cost effectiveness.
To assess whether patient outcomes and cost effectiveness have improved over the past 10 ...years.
Retrospective.
This study included 1,236 adult spinal deformity (ASD) patients.
Complications, reoperations, health related quality of life measures (HRQL), total cost, utility gained, quality adjusted life years (QALYs).
ASD patients with baseline (BL) and up to 2-year (2Y) HRQL data between the years of 2008-2019 were included. Incomplete yearly data from 2008 and 2019 were combined with 2009 and 2018, respectively. ANCOVA established estimated marginal means for outcome measures (complication rates, reoperations, HRQLs, total cost, utility gained, QALYs, cost efficiency cost per QALY) by year of initial surgery adjusting for covariates including age, gender, decompression or osteotomy, surgical approach, invasiveness, and BL deformity (pelvic tilt, pelvic incidence, lumbar lordosis). Trend-line slope indicated yearly changes. Cost was calculated using the PearlDiver database and assessed for complications/major complications and comorbidities according to CMS.gov definitions. These costs represented national averages of Medicare pay-scales for services within a 30-day window including length of stay and death differentiated by complication/comorbidity, revision, and surgical approach. Internal cost data were based on individual patient DRG codes, limiting revisions to those within 2 years of the initial surgery.
A total of 1,236 patients (2009: 117 patients, 2010: 97, 2011: 75, 2012: 45, 2013: 106, 2014: 127, 2015: 115, 2016: 204, 2017: 202, 2018: 148) were included with no significant differences in baseline ODI by year. There was an overall decrease in rates of any complication (0.78 vs 0.61), any reoperation (0.25 vs 0.10), and minor complication (0.54 vs 0.37) between 2009 and 2018 (all p<0.05). Minor complications decreased by 2.48% per year (R2=0.5179), with a 1.84% yearly decrease in any complication (R2=0.8322), 1.33% decrease in any reoperation (R2=0.2211), and 0.82% decrease in major complication (R2=0.1435). BL to 2Y difference in SF-36 PCS had the greatest improvement (0.2526 increase per year, R2=0.3985) and ODI BL to 2Y difference improved by 0.3687 per year (R2=0.3683). National average 2Y cost decreased at a yearly rate of $3,194 (R2=0.6602), 2Y utility gained had a yearly increase of 0.0041 (R2=0.57), 2Y QALYs gained increased yearly by 0.008 (R2=0.57), and 2Y cost per QALY decreased yearly by $39,953 (R2=0.6778). Adjusting for inflation since 2009, internal DRG data verified the trend of national average costs, as overall costs (including revisions within 2Y) have decreased at a rate of $793 each year (R2=0.0483). This resulted in a decrease in cost per QALY at 2Y of $19,903 per year (R2=0.3181).
Between 2008 and 2019, rates of complications have decreased concurrently with improvements in patient reported outcomes, resulting in improved cost effectiveness according to national Medicare average and individual patient cost data.
This abstract does not discuss or include any applicable devices or drugs.
Deterioration of global coronal alignment (GCA) may be associated with worse outcomes after adult spinal deformity (ASD) surgery. The impact of fusion length and upper instrumented vertebra (UIV) ...selection for patients with this complication is unclear.
Our objective was to compare outcomes for long sacropelvic fusions with upper-thoracic (UT) vs lower-thoracic (LT) UIV in patients with worsening GCA≥1cm.
Retrospective review of a prospectively collected multicenter case registry.
Database enrollment required age ≥18 years, scoliosis ≥20°, sagittal vertical axis (SVA) ≥5cm, pelvic tilt ≥25°, or thoracic kyphosis ≥60°.
Radiographic alignment, HRQL (Oswestry Disability Index ODI, Short Form-36 SF-36, Scoliosis Research Society-22 SRS-22r, numerical rating scale NRS back/leg pain scores), and complications.
This is a retrospective analysis of a prospective multicenter database of consecutive ASD patients. Index operations involved instrumented fusion from sacropelvis to thoracic spine. Global coronal deterioration was defined as worsening GCA≥1cm from preoperative to 2-year follow-up.
Of 875 potentially eligible patients, 560 (64%) had complete 2-year follow-up data, of which 144 (25.7%) demonstrated worse GCA at 2-year postop (UT 35.4%, LT 64.6%). At baseline, UT had younger age (61.6±9.9 vs 64.5±8.6years, p=0.008), more osteoporosis (35.3% vs 16.1%, p=0.009), and worse scoliosis (51.9±22.5° vs 32.5±16.3°, p<0.001). Index operations were comparable except UT had longer fusions (16.4±0.9 vs 9.7±1.2 levels, p<0.001) and operative duration (8.6±3.2 vs 7.6±3.0hrs, p=0.023). At 2-year follow-up, global coronal deterioration averaged 2.7±1.4cm (1.9 to 4.6cm, p<0.001), scoliosis improved (39.3±20.8° to 18.0±14.8°, p<0.001), and sagittal spinopelvic alignment improved significantly for all patients. UT maintained smaller positive C7-sagittal vertical axis (SVA) (2.7±5.7 vs 4.7±5.7cm, p=0.014). Postoperative 2-year health-related quality-of-life (HRQL) was significantly improved from baseline for all patients. Significant HRQL comparisons included: UT had worse SRS-22r Activity (3.2±1.0 vs 3.6±0.8, p=0.040) and SRS-22r Satisfaction (3.9±1.1 vs 4.3±0.8, p=0.021). Also, fewer UT patients improved by ≥1 minimal clinically important difference in leg pain NRS (41.3% vs 62.7%, p=0.020). Total reported complications (total=208, reoperation=53/major=77/minor=78) had comparable percentages of affected UT vs LT patients, but the percentage of re-operated patients was higher for UT (35.3% vs 18.3%, p=0.023). UT had higher reoperation rates for rod fracture (13.7% vs 2.2%, p=0.006), pseudarthrosis (7.8% vs 1.1%, p=0.006), but not proximal junctional kyphosis (9.8% vs 8.6%, p=0.810).
In ASD patients with worse 2-year GCA after long sacropelvic fusion, upper-thoracic UIV was associated with worse 2-year HRQL compared to lower-thoracic UIV. This may suggest residual global coronal malalignment is clinically less tolerated in ASD patients with longer fusions to proximal thoracic spine. These results can inform operative planning and improve patient counseling.
This abstract does not discuss or include any applicable devices or drugs.
Adult spinal deformity (ASD) patients experience markedly decreased health-related quality of life along many dimensions.
We hypothesized that ASD surgery would be associated with improved work- and ...school-related productivity, as well as decreased rates of absenteeism.
Retrospective cohort study.
Only patients eligible for 2-year follow-up were included, and those with a history of previous spinal fusion were excluded.
The primary outcome measures in this study were SRS-22r questions 9 (“What is your current level of work/school activity?”) and 17 (“In the last 3 months have you taken any days off of work, including household work, or school because of back pain?”).
A repeated measures mixed linear regression was used to analyze responses over time among patients managed operatively (OP) vs nonoperatively (NON-OP). Results were further stratified by baseline employment status, age, SVA, PI-LL, and deformity curve type.
In total, 1,188 patients were analyzed. Of those, 66.6% (n=792) were managed operatively. The vast majority (78.9%, n=934) were female. Patients were relatively evenly distributed across age groups (27.6% 0-49; 21.1% 50-59; 30.1% 60-69; 21.2% ≥70). At baseline, the mean percentage of activity at work/school was 56.4% (SD 35.4%), and the mean days off from work/school over the past 90 days was 1.6 (SD 1.8). Patients undergoing ASD surgery exhibited an 18.1% absolute increase in work/school productivity at 2-year follow-up vs baseline (p<0.0001), while no significant change was observed for the nonoperative cohort (p>0.5). Similarly, the OP cohort experienced 1.1 fewer absent days over the past 90 days at 2 years vs baseline (p<0.0001), while the NON-OP cohort showed no such difference (p>0.3). These differences were largely preserved after stratifying by baseline employment status, age group, SVA, PI-LL, and deformity curve type.
ASD patients managed operatively exhibited an average increase in work/school productivity of 18.1% and decreased absenteeism of 1.1 per 90 days at 2-year follow-up, while patients managed non-operatively did not exhibit change from baseline. Given the age distribution of patients in this study, these findings should be interpreted as pertaining primarily to obligations at work or within the home. Further study of the direct and indirect economic benefits of ASD surgery to patients is warranted.
This abstract does not discuss or include any applicable devices or drugs.
UV light pre-treatment was examined as a means of enriching the catalytic activation of oxygen by bimetallic AuPt deposits loaded on TiO
2
. The rate of catalytic oxygen activation was assessed by ...monitoring the rate of formic acid oxidation in an aqueous system. A catalytic synergy was observed to exist for the bimetallic AuPt on TiO
2
and was governed by the Au-Pt structure and ratio. The extent of the synergy was further enhanced upon UV light pre-treatment. Exceptional improvements in bimetallic catalysts are often simply attributed to a synergy effect, which is not necessarily well-understood. The Au-Pt bimetallic synergy and UV light pre-illumination phenomena were probed using high-end characterisation tools in conjunction with first principle calculations with the effects attributed to a combined influence of work-function difference and lattice mismatch between Au and Pt. Understanding the origin of bimetallic synergism is a critical step toward developing advanced catalysts.
UV pre-illumination-enhanced bimetallic synergy work-function-driven electron transfer pathway.
Au;
Pt;
oxygen;
electron.
Inflammatory biomarkers predict incident and recurrent cardiac events, but their relationship to stroke prognosis is uncertain. We hypothesized that high-sensitivity C-reactive protein (hsCRP) ...predicts recurrent ischemic stroke after recent lacunar stroke.
Levels of Inflammatory Markers in the Treatment of Stroke (LIMITS) was an international, multicenter, prospective ancillary biomarker study nested within Secondary Prevention of Small Subcortical Strokes (SPS3), a phase III trial in patients with recent lacunar stroke. Patients were assigned in factorial design to aspirin versus aspirin plus clopidogrel, and higher versus lower blood pressure targets. Patients had blood samples collected at enrollment and hsCRP measured using nephelometry at a central laboratory. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for recurrence risks before and after adjusting for demographics, comorbidities, and statin use.
Among 1244 patients with lacunar stroke (mean age, 63.3±10.8 years), median hsCRP was 2.16 mg/L. There were 83 recurrent ischemic strokes (including 45 lacunes) and 115 major vascular events (stroke, myocardial infarction, and vascular death). Compared with the bottom quartile, those in the top quartile (hsCRP>4.86 mg/L) were at increased risk of recurrent ischemic stroke (unadjusted HR, 2.54; 95% CI, 1.30-4.96), even after adjusting for demographics and risk factors (adjusted HR, 2.32; 95% CI, 1.15-4.68). hsCRP predicted increased risk of major vascular events (top quartile adjusted HR, 2.04; 95% CI, 1.14-3.67). There was no interaction with randomized antiplatelet treatment.
Among recent lacunar stroke patients, hsCRP levels predict the risk of recurrent strokes and other vascular events. hsCRP did not predict the response to dual antiplatelets.
http://www.clinicaltrials.gov. Unique identifier: NCT00059306.
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